diff options
Diffstat (limited to 'drivers/dma/loongson')
| -rw-r--r-- | drivers/dma/loongson/Kconfig | 41 | ||||
| -rw-r--r-- | drivers/dma/loongson/Makefile | 4 | ||||
| -rw-r--r-- | drivers/dma/loongson/loongson1-apb-dma.c | 660 | ||||
| -rw-r--r-- | drivers/dma/loongson/loongson2-apb-cmc-dma.c | 730 | ||||
| -rw-r--r-- | drivers/dma/loongson/loongson2-apb-dma.c | 686 |
5 files changed, 2121 insertions, 0 deletions
diff --git a/drivers/dma/loongson/Kconfig b/drivers/dma/loongson/Kconfig new file mode 100644 index 000000000..c4e62dce5 --- /dev/null +++ b/drivers/dma/loongson/Kconfig @@ -0,0 +1,41 @@ +# SPDX-License-Identifier: GPL-2.0-only +# +# Loongson DMA controllers drivers +# +if MACH_LOONGSON32 || MACH_LOONGSON64 || COMPILE_TEST + +config LOONGSON1_APB_DMA + tristate "Loongson1 APB DMA support" + depends on MACH_LOONGSON32 || COMPILE_TEST + select DMA_ENGINE + select DMA_VIRTUAL_CHANNELS + help + This selects support for the APB DMA controller in Loongson1 SoCs, + which is required by Loongson1 NAND and audio support. + +config LOONGSON2_APB_DMA + tristate "Loongson2 APB DMA support" + depends on MACH_LOONGSON64 || COMPILE_TEST + select DMA_ENGINE + select DMA_VIRTUAL_CHANNELS + help + Support for the Loongson2 APB DMA controller driver. The + DMA controller is having single DMA channel which can be + configured for different peripherals like audio, nand, sdio + etc which is in APB bus. + + This DMA controller transfers data from memory to peripheral fifo. + It does not support memory to memory data transfer. + +config LOONGSON2_APB_CMC_DMA + tristate "Loongson2 Chain Multi-Channel DMA support" + depends on MACH_LOONGSON64 || COMPILE_TEST + select DMA_ENGINE + select DMA_VIRTUAL_CHANNELS + help + Support for the Loongson Chain Multi-Channel DMA controller driver. + It is discovered on the Loongson-2K chip (Loongson-2K0300/Loongson-2K3000), + which has 4/8 channels internally, enabling bidirectional data transfer + between devices and memory. + +endif diff --git a/drivers/dma/loongson/Makefile b/drivers/dma/loongson/Makefile new file mode 100644 index 000000000..48c19781e --- /dev/null +++ b/drivers/dma/loongson/Makefile @@ -0,0 +1,4 @@ +# SPDX-License-Identifier: GPL-2.0-only +obj-$(CONFIG_LOONGSON1_APB_DMA) += loongson1-apb-dma.o +obj-$(CONFIG_LOONGSON2_APB_DMA) += loongson2-apb-dma.o +obj-$(CONFIG_LOONGSON2_APB_CMC_DMA) += loongson2-apb-cmc-dma.o diff --git a/drivers/dma/loongson/loongson1-apb-dma.c b/drivers/dma/loongson/loongson1-apb-dma.c new file mode 100644 index 000000000..89786cbd2 --- /dev/null +++ b/drivers/dma/loongson/loongson1-apb-dma.c @@ -0,0 +1,660 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Driver for Loongson-1 APB DMA Controller + * + * Copyright (C) 2015-2024 Keguang Zhang <keguang.zhang@gmail.com> + */ + +#include <linux/dmapool.h> +#include <linux/dma-mapping.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/iopoll.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_dma.h> +#include <linux/platform_device.h> +#include <linux/slab.h> + +#include "../dmaengine.h" +#include "../virt-dma.h" + +/* Loongson-1 DMA Control Register */ +#define LS1X_DMA_CTRL 0x0 + +/* DMA Control Register Bits */ +#define LS1X_DMA_STOP BIT(4) +#define LS1X_DMA_START BIT(3) +#define LS1X_DMA_ASK_VALID BIT(2) + +/* DMA Next Field Bits */ +#define LS1X_DMA_NEXT_VALID BIT(0) + +/* DMA Command Field Bits */ +#define LS1X_DMA_RAM2DEV BIT(12) +#define LS1X_DMA_INT BIT(1) +#define LS1X_DMA_INT_MASK BIT(0) + +#define LS1X_DMA_LLI_ALIGNMENT 64 +#define LS1X_DMA_LLI_ADDR_MASK GENMASK(31, __ffs(LS1X_DMA_LLI_ALIGNMENT)) +#define LS1X_DMA_MAX_CHANNELS 3 + +enum ls1x_dmadesc_offsets { + LS1X_DMADESC_NEXT = 0, + LS1X_DMADESC_SADDR, + LS1X_DMADESC_DADDR, + LS1X_DMADESC_LENGTH, + LS1X_DMADESC_STRIDE, + LS1X_DMADESC_CYCLES, + LS1X_DMADESC_CMD, + LS1X_DMADESC_SIZE +}; + +struct ls1x_dma_lli { + unsigned int hw[LS1X_DMADESC_SIZE]; + dma_addr_t phys; + struct list_head node; +} __aligned(LS1X_DMA_LLI_ALIGNMENT); + +struct ls1x_dma_desc { + struct virt_dma_desc vd; + struct list_head lli_list; +}; + +struct ls1x_dma_chan { + struct virt_dma_chan vc; + struct dma_pool *lli_pool; + phys_addr_t src_addr; + phys_addr_t dst_addr; + enum dma_slave_buswidth src_addr_width; + enum dma_slave_buswidth dst_addr_width; + unsigned int bus_width; + void __iomem *reg_base; + int irq; + bool is_cyclic; + struct ls1x_dma_lli *curr_lli; +}; + +struct ls1x_dma { + struct dma_device ddev; + unsigned int nr_chans; + struct ls1x_dma_chan chan[]; +}; + +static irqreturn_t ls1x_dma_irq_handler(int irq, void *data); + +#define to_ls1x_dma_chan(dchan) \ + container_of(dchan, struct ls1x_dma_chan, vc.chan) + +#define to_ls1x_dma_desc(d) \ + container_of(d, struct ls1x_dma_desc, vd) + +static inline struct device *chan2dev(struct dma_chan *chan) +{ + return &chan->dev->device; +} + +static inline int ls1x_dma_query(struct ls1x_dma_chan *chan, + dma_addr_t *lli_phys) +{ + struct dma_chan *dchan = &chan->vc.chan; + int val, ret; + + val = *lli_phys & LS1X_DMA_LLI_ADDR_MASK; + val |= LS1X_DMA_ASK_VALID; + val |= dchan->chan_id; + writel(val, chan->reg_base + LS1X_DMA_CTRL); + ret = readl_poll_timeout_atomic(chan->reg_base + LS1X_DMA_CTRL, val, + !(val & LS1X_DMA_ASK_VALID), 0, 3000); + if (ret) + dev_err(chan2dev(dchan), "failed to query DMA\n"); + + return ret; +} + +static inline int ls1x_dma_start(struct ls1x_dma_chan *chan, + dma_addr_t *lli_phys) +{ + struct dma_chan *dchan = &chan->vc.chan; + struct device *dev = chan2dev(dchan); + int val, ret; + + val = *lli_phys & LS1X_DMA_LLI_ADDR_MASK; + val |= LS1X_DMA_START; + val |= dchan->chan_id; + writel(val, chan->reg_base + LS1X_DMA_CTRL); + ret = readl_poll_timeout(chan->reg_base + LS1X_DMA_CTRL, val, + !(val & LS1X_DMA_START), 0, 1000); + if (!ret) + dev_dbg(dev, "start DMA with lli_phys=%pad\n", lli_phys); + else + dev_err(dev, "failed to start DMA\n"); + + return ret; +} + +static inline void ls1x_dma_stop(struct ls1x_dma_chan *chan) +{ + int val = readl(chan->reg_base + LS1X_DMA_CTRL); + + writel(val | LS1X_DMA_STOP, chan->reg_base + LS1X_DMA_CTRL); +} + +static void ls1x_dma_free_chan_resources(struct dma_chan *dchan) +{ + struct ls1x_dma_chan *chan = to_ls1x_dma_chan(dchan); + struct device *dev = chan2dev(dchan); + + dma_free_coherent(dev, sizeof(struct ls1x_dma_lli), + chan->curr_lli, chan->curr_lli->phys); + dma_pool_destroy(chan->lli_pool); + chan->lli_pool = NULL; + devm_free_irq(dev, chan->irq, chan); + vchan_free_chan_resources(&chan->vc); +} + +static int ls1x_dma_alloc_chan_resources(struct dma_chan *dchan) +{ + struct ls1x_dma_chan *chan = to_ls1x_dma_chan(dchan); + struct device *dev = chan2dev(dchan); + dma_addr_t phys; + int ret; + + ret = devm_request_irq(dev, chan->irq, ls1x_dma_irq_handler, + IRQF_SHARED, dma_chan_name(dchan), chan); + if (ret) { + dev_err(dev, "failed to request IRQ %d\n", chan->irq); + return ret; + } + + chan->lli_pool = dma_pool_create(dma_chan_name(dchan), dev, + sizeof(struct ls1x_dma_lli), + __alignof__(struct ls1x_dma_lli), 0); + if (!chan->lli_pool) + return -ENOMEM; + + /* allocate memory for querying the current lli */ + dma_set_coherent_mask(dev, DMA_BIT_MASK(32)); + chan->curr_lli = dma_alloc_coherent(dev, sizeof(struct ls1x_dma_lli), + &phys, GFP_KERNEL); + if (!chan->curr_lli) { + dma_pool_destroy(chan->lli_pool); + return -ENOMEM; + } + chan->curr_lli->phys = phys; + + return 0; +} + +static void ls1x_dma_free_desc(struct virt_dma_desc *vd) +{ + struct ls1x_dma_desc *desc = to_ls1x_dma_desc(vd); + struct ls1x_dma_chan *chan = to_ls1x_dma_chan(vd->tx.chan); + struct ls1x_dma_lli *lli, *_lli; + + list_for_each_entry_safe(lli, _lli, &desc->lli_list, node) { + list_del(&lli->node); + dma_pool_free(chan->lli_pool, lli, lli->phys); + } + + kfree(desc); +} + +static struct ls1x_dma_desc *ls1x_dma_alloc_desc(void) +{ + struct ls1x_dma_desc *desc; + + desc = kzalloc_obj(*desc, GFP_NOWAIT); + if (!desc) + return NULL; + + INIT_LIST_HEAD(&desc->lli_list); + + return desc; +} + +static int ls1x_dma_prep_lli(struct dma_chan *dchan, struct ls1x_dma_desc *desc, + struct scatterlist *sgl, unsigned int sg_len, + enum dma_transfer_direction dir, bool is_cyclic) +{ + struct ls1x_dma_chan *chan = to_ls1x_dma_chan(dchan); + struct ls1x_dma_lli *lli, *prev = NULL, *first = NULL; + struct device *dev = chan2dev(dchan); + struct list_head *pos = NULL; + struct scatterlist *sg; + unsigned int dev_addr, cmd, i; + + switch (dir) { + case DMA_MEM_TO_DEV: + dev_addr = chan->dst_addr; + chan->bus_width = chan->dst_addr_width; + cmd = LS1X_DMA_RAM2DEV | LS1X_DMA_INT; + break; + case DMA_DEV_TO_MEM: + dev_addr = chan->src_addr; + chan->bus_width = chan->src_addr_width; + cmd = LS1X_DMA_INT; + break; + default: + dev_err(dev, "unsupported DMA direction: %s\n", + dmaengine_get_direction_text(dir)); + return -EINVAL; + } + + for_each_sg(sgl, sg, sg_len, i) { + dma_addr_t buf_addr = sg_dma_address(sg); + size_t buf_len = sg_dma_len(sg); + dma_addr_t phys; + + if (!is_dma_copy_aligned(dchan->device, buf_addr, 0, buf_len)) { + dev_err(dev, "buffer is not aligned\n"); + return -EINVAL; + } + + /* allocate HW descriptors */ + lli = dma_pool_zalloc(chan->lli_pool, GFP_NOWAIT, &phys); + if (!lli) { + dev_err(dev, "failed to alloc lli %u\n", i); + return -ENOMEM; + } + + /* setup HW descriptors */ + lli->phys = phys; + lli->hw[LS1X_DMADESC_SADDR] = buf_addr; + lli->hw[LS1X_DMADESC_DADDR] = dev_addr; + lli->hw[LS1X_DMADESC_LENGTH] = buf_len / chan->bus_width; + lli->hw[LS1X_DMADESC_STRIDE] = 0; + lli->hw[LS1X_DMADESC_CYCLES] = 1; + lli->hw[LS1X_DMADESC_CMD] = cmd; + + if (prev) + prev->hw[LS1X_DMADESC_NEXT] = + lli->phys | LS1X_DMA_NEXT_VALID; + prev = lli; + + if (!first) + first = lli; + + list_add_tail(&lli->node, &desc->lli_list); + } + + if (is_cyclic) { + lli->hw[LS1X_DMADESC_NEXT] = first->phys | LS1X_DMA_NEXT_VALID; + chan->is_cyclic = is_cyclic; + } + + list_for_each(pos, &desc->lli_list) { + lli = list_entry(pos, struct ls1x_dma_lli, node); + print_hex_dump_debug("LLI: ", DUMP_PREFIX_OFFSET, 16, 4, + lli, sizeof(*lli), false); + } + + return 0; +} + +static struct dma_async_tx_descriptor * +ls1x_dma_prep_slave_sg(struct dma_chan *dchan, struct scatterlist *sgl, + unsigned int sg_len, enum dma_transfer_direction dir, + unsigned long flags, void *context) +{ + struct ls1x_dma_desc *desc; + + dev_dbg(chan2dev(dchan), "sg_len=%u flags=0x%lx dir=%s\n", + sg_len, flags, dmaengine_get_direction_text(dir)); + + desc = ls1x_dma_alloc_desc(); + if (!desc) + return NULL; + + if (ls1x_dma_prep_lli(dchan, desc, sgl, sg_len, dir, false)) { + ls1x_dma_free_desc(&desc->vd); + return NULL; + } + + return vchan_tx_prep(to_virt_chan(dchan), &desc->vd, flags); +} + +static struct dma_async_tx_descriptor * +ls1x_dma_prep_dma_cyclic(struct dma_chan *dchan, dma_addr_t buf_addr, + size_t buf_len, size_t period_len, + enum dma_transfer_direction dir, unsigned long flags) +{ + struct ls1x_dma_desc *desc; + struct scatterlist *sgl; + unsigned int sg_len; + unsigned int i; + int ret; + + dev_dbg(chan2dev(dchan), + "buf_len=%zu period_len=%zu flags=0x%lx dir=%s\n", + buf_len, period_len, flags, dmaengine_get_direction_text(dir)); + + desc = ls1x_dma_alloc_desc(); + if (!desc) + return NULL; + + /* allocate the scatterlist */ + sg_len = buf_len / period_len; + sgl = kmalloc_objs(*sgl, sg_len, GFP_NOWAIT); + if (!sgl) + return NULL; + + sg_init_table(sgl, sg_len); + for (i = 0; i < sg_len; ++i) { + sg_set_page(&sgl[i], pfn_to_page(PFN_DOWN(buf_addr)), + period_len, offset_in_page(buf_addr)); + sg_dma_address(&sgl[i]) = buf_addr; + sg_dma_len(&sgl[i]) = period_len; + buf_addr += period_len; + } + + ret = ls1x_dma_prep_lli(dchan, desc, sgl, sg_len, dir, true); + kfree(sgl); + if (ret) { + ls1x_dma_free_desc(&desc->vd); + return NULL; + } + + return vchan_tx_prep(to_virt_chan(dchan), &desc->vd, flags); +} + +static int ls1x_dma_slave_config(struct dma_chan *dchan, + struct dma_slave_config *config) +{ + struct ls1x_dma_chan *chan = to_ls1x_dma_chan(dchan); + + chan->src_addr = config->src_addr; + chan->src_addr_width = config->src_addr_width; + chan->dst_addr = config->dst_addr; + chan->dst_addr_width = config->dst_addr_width; + + return 0; +} + +static int ls1x_dma_pause(struct dma_chan *dchan) +{ + struct ls1x_dma_chan *chan = to_ls1x_dma_chan(dchan); + int ret; + + guard(spinlock_irqsave)(&chan->vc.lock); + /* save the current lli */ + ret = ls1x_dma_query(chan, &chan->curr_lli->phys); + if (!ret) + ls1x_dma_stop(chan); + + return ret; +} + +static int ls1x_dma_resume(struct dma_chan *dchan) +{ + struct ls1x_dma_chan *chan = to_ls1x_dma_chan(dchan); + + guard(spinlock_irqsave)(&chan->vc.lock); + + return ls1x_dma_start(chan, &chan->curr_lli->phys); +} + +static int ls1x_dma_terminate_all(struct dma_chan *dchan) +{ + struct ls1x_dma_chan *chan = to_ls1x_dma_chan(dchan); + struct virt_dma_desc *vd; + LIST_HEAD(head); + + ls1x_dma_stop(chan); + + scoped_guard(spinlock_irqsave, &chan->vc.lock) { + vd = vchan_next_desc(&chan->vc); + if (vd) + vchan_terminate_vdesc(vd); + + vchan_get_all_descriptors(&chan->vc, &head); + } + + vchan_dma_desc_free_list(&chan->vc, &head); + + return 0; +} + +static void ls1x_dma_synchronize(struct dma_chan *dchan) +{ + vchan_synchronize(to_virt_chan(dchan)); +} + +static enum dma_status ls1x_dma_tx_status(struct dma_chan *dchan, + dma_cookie_t cookie, + struct dma_tx_state *state) +{ + struct ls1x_dma_chan *chan = to_ls1x_dma_chan(dchan); + struct virt_dma_desc *vd; + enum dma_status status; + size_t bytes = 0; + + status = dma_cookie_status(dchan, cookie, state); + if (status == DMA_COMPLETE) + return status; + + scoped_guard(spinlock_irqsave, &chan->vc.lock) { + vd = vchan_find_desc(&chan->vc, cookie); + if (vd) { + struct ls1x_dma_desc *desc = to_ls1x_dma_desc(vd); + struct ls1x_dma_lli *lli; + dma_addr_t next_phys; + + /* get the current lli */ + if (ls1x_dma_query(chan, &chan->curr_lli->phys)) + return status; + + /* locate the current lli */ + next_phys = chan->curr_lli->hw[LS1X_DMADESC_NEXT]; + list_for_each_entry(lli, &desc->lli_list, node) + if (lli->hw[LS1X_DMADESC_NEXT] == next_phys) + break; + + dev_dbg(chan2dev(dchan), "current lli_phys=%pad", + &lli->phys); + + /* count the residues */ + list_for_each_entry_from(lli, &desc->lli_list, node) + bytes += lli->hw[LS1X_DMADESC_LENGTH] * + chan->bus_width; + } + } + + dma_set_residue(state, bytes); + + return status; +} + +static void ls1x_dma_issue_pending(struct dma_chan *dchan) +{ + struct ls1x_dma_chan *chan = to_ls1x_dma_chan(dchan); + + guard(spinlock_irqsave)(&chan->vc.lock); + + if (vchan_issue_pending(&chan->vc)) { + struct virt_dma_desc *vd = vchan_next_desc(&chan->vc); + + if (vd) { + struct ls1x_dma_desc *desc = to_ls1x_dma_desc(vd); + struct ls1x_dma_lli *lli; + + lli = list_first_entry(&desc->lli_list, + struct ls1x_dma_lli, node); + ls1x_dma_start(chan, &lli->phys); + } + } +} + +static irqreturn_t ls1x_dma_irq_handler(int irq, void *data) +{ + struct ls1x_dma_chan *chan = data; + struct dma_chan *dchan = &chan->vc.chan; + struct device *dev = chan2dev(dchan); + struct virt_dma_desc *vd; + + scoped_guard(spinlock, &chan->vc.lock) { + vd = vchan_next_desc(&chan->vc); + if (!vd) { + dev_warn(dev, + "IRQ %d with no active desc on channel %d\n", + irq, dchan->chan_id); + return IRQ_NONE; + } + + if (chan->is_cyclic) { + vchan_cyclic_callback(vd); + } else { + list_del(&vd->node); + vchan_cookie_complete(vd); + } + } + + dev_dbg(dev, "DMA IRQ %d on channel %d\n", irq, dchan->chan_id); + + return IRQ_HANDLED; +} + +static int ls1x_dma_chan_probe(struct platform_device *pdev, + struct ls1x_dma *dma) +{ + void __iomem *reg_base; + int id; + + reg_base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(reg_base)) + return PTR_ERR(reg_base); + + for (id = 0; id < dma->nr_chans; id++) { + struct ls1x_dma_chan *chan = &dma->chan[id]; + char pdev_irqname[16]; + + snprintf(pdev_irqname, sizeof(pdev_irqname), "ch%d", id); + chan->irq = platform_get_irq_byname(pdev, pdev_irqname); + if (chan->irq < 0) + return dev_err_probe(&pdev->dev, chan->irq, + "failed to get IRQ for ch%d\n", + id); + + chan->reg_base = reg_base; + chan->vc.desc_free = ls1x_dma_free_desc; + vchan_init(&chan->vc, &dma->ddev); + } + + return 0; +} + +static void ls1x_dma_chan_remove(struct ls1x_dma *dma) +{ + int id; + + for (id = 0; id < dma->nr_chans; id++) { + struct ls1x_dma_chan *chan = &dma->chan[id]; + + if (chan->vc.chan.device == &dma->ddev) { + list_del(&chan->vc.chan.device_node); + tasklet_kill(&chan->vc.task); + } + } +} + +static int ls1x_dma_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct dma_device *ddev; + struct ls1x_dma *dma; + int ret; + + ret = platform_irq_count(pdev); + if (ret <= 0 || ret > LS1X_DMA_MAX_CHANNELS) + return dev_err_probe(dev, -EINVAL, + "Invalid number of IRQ channels: %d\n", + ret); + + dma = devm_kzalloc(dev, struct_size(dma, chan, ret), GFP_KERNEL); + if (!dma) + return -ENOMEM; + dma->nr_chans = ret; + + /* initialize DMA device */ + ddev = &dma->ddev; + ddev->dev = dev; + ddev->copy_align = DMAENGINE_ALIGN_4_BYTES; + ddev->src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | + BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | + BIT(DMA_SLAVE_BUSWIDTH_4_BYTES); + ddev->dst_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | + BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | + BIT(DMA_SLAVE_BUSWIDTH_4_BYTES); + ddev->directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV); + ddev->residue_granularity = DMA_RESIDUE_GRANULARITY_SEGMENT; + ddev->device_alloc_chan_resources = ls1x_dma_alloc_chan_resources; + ddev->device_free_chan_resources = ls1x_dma_free_chan_resources; + ddev->device_prep_slave_sg = ls1x_dma_prep_slave_sg; + ddev->device_prep_dma_cyclic = ls1x_dma_prep_dma_cyclic; + ddev->device_config = ls1x_dma_slave_config; + ddev->device_pause = ls1x_dma_pause; + ddev->device_resume = ls1x_dma_resume; + ddev->device_terminate_all = ls1x_dma_terminate_all; + ddev->device_synchronize = ls1x_dma_synchronize; + ddev->device_tx_status = ls1x_dma_tx_status; + ddev->device_issue_pending = ls1x_dma_issue_pending; + dma_cap_set(DMA_SLAVE, ddev->cap_mask); + INIT_LIST_HEAD(&ddev->channels); + + /* initialize DMA channels */ + ret = ls1x_dma_chan_probe(pdev, dma); + if (ret) + goto err; + + ret = dmaenginem_async_device_register(ddev); + if (ret) { + dev_err(dev, "failed to register DMA device\n"); + goto err; + } + + ret = of_dma_controller_register(dev->of_node, of_dma_xlate_by_chan_id, + ddev); + if (ret) { + dev_err(dev, "failed to register DMA controller\n"); + goto err; + } + + platform_set_drvdata(pdev, dma); + dev_info(dev, "Loongson1 DMA driver registered\n"); + + return 0; + +err: + ls1x_dma_chan_remove(dma); + + return ret; +} + +static void ls1x_dma_remove(struct platform_device *pdev) +{ + struct ls1x_dma *dma = platform_get_drvdata(pdev); + + of_dma_controller_free(pdev->dev.of_node); + ls1x_dma_chan_remove(dma); +} + +static const struct of_device_id ls1x_dma_match[] = { + { .compatible = "loongson,ls1b-apbdma" }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, ls1x_dma_match); + +static struct platform_driver ls1x_dma_driver = { + .probe = ls1x_dma_probe, + .remove = ls1x_dma_remove, + .driver = { + .name = KBUILD_MODNAME, + .of_match_table = ls1x_dma_match, + }, +}; + +module_platform_driver(ls1x_dma_driver); + +MODULE_AUTHOR("Keguang Zhang <keguang.zhang@gmail.com>"); +MODULE_DESCRIPTION("Loongson-1 APB DMA Controller driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/dma/loongson/loongson2-apb-cmc-dma.c b/drivers/dma/loongson/loongson2-apb-cmc-dma.c new file mode 100644 index 000000000..1c9a542ed --- /dev/null +++ b/drivers/dma/loongson/loongson2-apb-cmc-dma.c @@ -0,0 +1,730 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Loongson-2 Chain Multi-Channel DMA Controller driver + * + * Copyright (C) 2024-2026 Loongson Technology Corporation Limited + */ + +#include <linux/acpi.h> +#include <linux/acpi_dma.h> +#include <linux/bitfield.h> +#include <linux/clk.h> +#include <linux/dma-mapping.h> +#include <linux/dmapool.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_dma.h> +#include <linux/platform_device.h> +#include <linux/slab.h> + +#include "../dmaengine.h" +#include "../virt-dma.h" + +#define LOONGSON2_CMCDMA_ISR 0x0 /* DMA Interrupt Status Register */ +#define LOONGSON2_CMCDMA_IFCR 0x4 /* DMA Interrupt Flag Clear Register */ +#define LOONGSON2_CMCDMA_CCR 0x8 /* DMA Channel Configuration Register */ +#define LOONGSON2_CMCDMA_CNDTR 0xc /* DMA Channel Transmit Count Register */ +#define LOONGSON2_CMCDMA_CPAR 0x10 /* DMA Channel Peripheral Address Register */ +#define LOONGSON2_CMCDMA_CMAR 0x14 /* DMA Channel Memory Address Register */ + +/* Bitfields of DMA interrupt status register */ +#define LOONGSON2_CMCDMA_TCI BIT(1) /* Transfer Complete Interrupt */ +#define LOONGSON2_CMCDMA_HTI BIT(2) /* Half Transfer Interrupt */ +#define LOONGSON2_CMCDMA_TEI BIT(3) /* Transfer Error Interrupt */ + +#define LOONGSON2_CMCDMA_MASKI \ + (LOONGSON2_CMCDMA_TCI | LOONGSON2_CMCDMA_HTI | LOONGSON2_CMCDMA_TEI) + +/* Bitfields of DMA channel x Configuration Register */ +#define LOONGSON2_CMCDMA_CCR_EN BIT(0) /* Stream Enable */ +#define LOONGSON2_CMCDMA_CCR_TCIE BIT(1) /* Transfer Complete Interrupt Enable */ +#define LOONGSON2_CMCDMA_CCR_HTIE BIT(2) /* Half Transfer Complete Interrupt Enable */ +#define LOONGSON2_CMCDMA_CCR_TEIE BIT(3) /* Transfer Error Interrupt Enable */ +#define LOONGSON2_CMCDMA_CCR_DIR BIT(4) /* Data Transfer Direction */ +#define LOONGSON2_CMCDMA_CCR_CIRC BIT(5) /* Circular mode */ +#define LOONGSON2_CMCDMA_CCR_PINC BIT(6) /* Peripheral increment mode */ +#define LOONGSON2_CMCDMA_CCR_MINC BIT(7) /* Memory increment mode */ +#define LOONGSON2_CMCDMA_CCR_PSIZE_MASK GENMASK(9, 8) +#define LOONGSON2_CMCDMA_CCR_MSIZE_MASK GENMASK(11, 10) +#define LOONGSON2_CMCDMA_CCR_PL_MASK GENMASK(13, 12) +#define LOONGSON2_CMCDMA_CCR_M2M BIT(14) + +#define LOONGSON2_CMCDMA_CCR_CFG_MASK \ + (LOONGSON2_CMCDMA_CCR_PINC | LOONGSON2_CMCDMA_CCR_MINC | LOONGSON2_CMCDMA_CCR_PL_MASK) + +#define LOONGSON2_CMCDMA_CCR_IRQ_MASK \ + (LOONGSON2_CMCDMA_CCR_TCIE | LOONGSON2_CMCDMA_CCR_HTIE | LOONGSON2_CMCDMA_CCR_TEIE) + +#define LOONGSON2_CMCDMA_STREAM_MASK \ + (LOONGSON2_CMCDMA_CCR_CFG_MASK | LOONGSON2_CMCDMA_CCR_IRQ_MASK) + +#define LOONGSON2_CMCDMA_BUSWIDTHS (BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | \ + BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | \ + BIT(DMA_SLAVE_BUSWIDTH_4_BYTES)) + +#define LOONSON2_CMCDMA_MAX_DATA_ITEMS SZ_64K + +struct loongson2_cmc_dma_chan_reg { + u32 ccr; + u32 cndtr; + u32 cpar; + u32 cmar; +}; + +struct loongson2_cmc_dma_sg_req { + u32 len; + struct loongson2_cmc_dma_chan_reg chan_reg; +}; + +struct loongson2_cmc_dma_desc { + struct virt_dma_desc vdesc; + bool cyclic; + u32 num_sgs; + struct loongson2_cmc_dma_sg_req sg_req[] __counted_by(num_sgs); +}; + +struct loongson2_cmc_dma_chan { + struct virt_dma_chan vchan; + struct dma_slave_config dma_sconfig; + struct loongson2_cmc_dma_desc *desc; + u32 id; + u32 irq; + u32 next_sg; + struct loongson2_cmc_dma_chan_reg chan_reg; +}; + +struct loongson2_cmc_dma_dev { + struct dma_device ddev; + struct clk *dma_clk; + void __iomem *base; + u32 nr_channels; + u32 chan_reg_offset; + struct loongson2_cmc_dma_chan chan[] __counted_by(nr_channels); +}; + +struct loongson2_cmc_dma_config { + u32 max_channels; + u32 chan_reg_offset; +}; + +static const struct loongson2_cmc_dma_config ls2k0300_cmc_dma_config = { + .max_channels = 8, + .chan_reg_offset = 0x14, +}; + +static const struct loongson2_cmc_dma_config ls2k3000_cmc_dma_config = { + .max_channels = 4, + .chan_reg_offset = 0x18, +}; + +static struct loongson2_cmc_dma_dev *lmdma_get_dev(struct loongson2_cmc_dma_chan *lchan) +{ + return container_of(lchan->vchan.chan.device, struct loongson2_cmc_dma_dev, ddev); +} + +static struct loongson2_cmc_dma_chan *to_lmdma_chan(struct dma_chan *chan) +{ + return container_of(chan, struct loongson2_cmc_dma_chan, vchan.chan); +} + +static struct loongson2_cmc_dma_desc *to_lmdma_desc(struct virt_dma_desc *vdesc) +{ + return container_of(vdesc, struct loongson2_cmc_dma_desc, vdesc); +} + +static struct device *chan2dev(struct loongson2_cmc_dma_chan *lchan) +{ + return &lchan->vchan.chan.dev->device; +} + +static u32 loongson2_cmc_dma_read(struct loongson2_cmc_dma_dev *lddev, u32 reg, u32 id) +{ + return readl(lddev->base + (reg + lddev->chan_reg_offset * id)); +} + +static void loongson2_cmc_dma_write(struct loongson2_cmc_dma_dev *lddev, u32 reg, u32 id, u32 val) +{ + writel(val, lddev->base + (reg + lddev->chan_reg_offset * id)); +} + +static int loongson2_cmc_dma_get_width(enum dma_slave_buswidth width) +{ + switch (width) { + case DMA_SLAVE_BUSWIDTH_1_BYTE: + case DMA_SLAVE_BUSWIDTH_2_BYTES: + case DMA_SLAVE_BUSWIDTH_4_BYTES: + return ffs(width) - 1; + default: + return -EINVAL; + } +} + +static int loongson2_cmc_dma_slave_config(struct dma_chan *chan, struct dma_slave_config *config) +{ + struct loongson2_cmc_dma_chan *lchan = to_lmdma_chan(chan); + + memcpy(&lchan->dma_sconfig, config, sizeof(*config)); + + return 0; +} + +static void loongson2_cmc_dma_irq_clear(struct loongson2_cmc_dma_chan *lchan, u32 flags) +{ + struct loongson2_cmc_dma_dev *lddev = lmdma_get_dev(lchan); + u32 ifcr; + + ifcr = flags << (4 * lchan->id); + loongson2_cmc_dma_write(lddev, LOONGSON2_CMCDMA_IFCR, 0, ifcr); +} + +static void loongson2_cmc_dma_stop(struct loongson2_cmc_dma_chan *lchan) +{ + struct loongson2_cmc_dma_dev *lddev = lmdma_get_dev(lchan); + u32 ccr; + + ccr = loongson2_cmc_dma_read(lddev, LOONGSON2_CMCDMA_CCR, lchan->id); + ccr &= ~(LOONGSON2_CMCDMA_CCR_IRQ_MASK | LOONGSON2_CMCDMA_CCR_EN); + loongson2_cmc_dma_write(lddev, LOONGSON2_CMCDMA_CCR, lchan->id, ccr); + + loongson2_cmc_dma_irq_clear(lchan, LOONGSON2_CMCDMA_MASKI); +} + +static int loongson2_cmc_dma_terminate_all(struct dma_chan *chan) +{ + struct loongson2_cmc_dma_chan *lchan = to_lmdma_chan(chan); + + LIST_HEAD(head); + + scoped_guard(spinlock_irqsave, &lchan->vchan.lock) { + if (lchan->desc) { + vchan_terminate_vdesc(&lchan->desc->vdesc); + loongson2_cmc_dma_stop(lchan); + lchan->desc = NULL; + } + vchan_get_all_descriptors(&lchan->vchan, &head); + } + + vchan_dma_desc_free_list(&lchan->vchan, &head); + + return 0; +} + +static void loongson2_cmc_dma_synchronize(struct dma_chan *chan) +{ + struct loongson2_cmc_dma_chan *lchan = to_lmdma_chan(chan); + + vchan_synchronize(&lchan->vchan); +} + +static void loongson2_cmc_dma_start_transfer(struct loongson2_cmc_dma_chan *lchan) +{ + struct loongson2_cmc_dma_dev *lddev = lmdma_get_dev(lchan); + struct loongson2_cmc_dma_sg_req *sg_req; + struct loongson2_cmc_dma_chan_reg *reg; + struct virt_dma_desc *vdesc; + + loongson2_cmc_dma_stop(lchan); + + if (!lchan->desc) { + vdesc = vchan_next_desc(&lchan->vchan); + if (!vdesc) + return; + + list_del(&vdesc->node); + lchan->desc = to_lmdma_desc(vdesc); + lchan->next_sg = 0; + } + + if (lchan->next_sg == lchan->desc->num_sgs) + lchan->next_sg = 0; + + sg_req = &lchan->desc->sg_req[lchan->next_sg]; + reg = &sg_req->chan_reg; + + loongson2_cmc_dma_write(lddev, LOONGSON2_CMCDMA_CCR, lchan->id, reg->ccr); + loongson2_cmc_dma_write(lddev, LOONGSON2_CMCDMA_CNDTR, lchan->id, reg->cndtr); + loongson2_cmc_dma_write(lddev, LOONGSON2_CMCDMA_CPAR, lchan->id, reg->cpar); + loongson2_cmc_dma_write(lddev, LOONGSON2_CMCDMA_CMAR, lchan->id, reg->cmar); + + lchan->next_sg++; + + /* Start DMA */ + reg->ccr |= LOONGSON2_CMCDMA_CCR_EN; + loongson2_cmc_dma_write(lddev, LOONGSON2_CMCDMA_CCR, lchan->id, reg->ccr); +} + +static void loongson2_cmc_dma_configure_next_sg(struct loongson2_cmc_dma_chan *lchan) +{ + struct loongson2_cmc_dma_dev *lddev = lmdma_get_dev(lchan); + struct loongson2_cmc_dma_sg_req *sg_req; + u32 ccr, id = lchan->id; + + if (lchan->next_sg == lchan->desc->num_sgs) + lchan->next_sg = 0; + + /* Stop to update mem addr */ + ccr = loongson2_cmc_dma_read(lddev, LOONGSON2_CMCDMA_CCR, id); + ccr &= ~LOONGSON2_CMCDMA_CCR_EN; + loongson2_cmc_dma_write(lddev, LOONGSON2_CMCDMA_CCR, id, ccr); + + sg_req = &lchan->desc->sg_req[lchan->next_sg]; + loongson2_cmc_dma_write(lddev, LOONGSON2_CMCDMA_CMAR, id, sg_req->chan_reg.cmar); + + /* Start transition */ + ccr |= LOONGSON2_CMCDMA_CCR_EN; + loongson2_cmc_dma_write(lddev, LOONGSON2_CMCDMA_CCR, id, ccr); +} + +static void loongson2_cmc_dma_handle_chan_done(struct loongson2_cmc_dma_chan *lchan) +{ + if (!lchan->desc) + return; + + if (lchan->desc->cyclic) { + vchan_cyclic_callback(&lchan->desc->vdesc); + /* LOONGSON2_CMCDMA_CCR_CIRC mode don't need update register */ + if (lchan->desc->num_sgs == 1) + return; + loongson2_cmc_dma_configure_next_sg(lchan); + lchan->next_sg++; + } else { + if (lchan->next_sg == lchan->desc->num_sgs) { + vchan_cookie_complete(&lchan->desc->vdesc); + lchan->desc = NULL; + } + loongson2_cmc_dma_start_transfer(lchan); + } +} + +static irqreturn_t loongson2_cmc_dma_chan_irq(int irq, void *devid) +{ + struct loongson2_cmc_dma_chan *lchan = devid; + struct loongson2_cmc_dma_dev *lddev = lmdma_get_dev(lchan); + struct device *dev = chan2dev(lchan); + u32 ists, status, ccr; + + scoped_guard(spinlock, &lchan->vchan.lock) { + ccr = loongson2_cmc_dma_read(lddev, LOONGSON2_CMCDMA_CCR, lchan->id); + ists = loongson2_cmc_dma_read(lddev, LOONGSON2_CMCDMA_ISR, 0); + status = (ists >> (4 * lchan->id)) & LOONGSON2_CMCDMA_MASKI; + + loongson2_cmc_dma_irq_clear(lchan, status); + + if (status & LOONGSON2_CMCDMA_TCI) { + loongson2_cmc_dma_handle_chan_done(lchan); + status &= ~LOONGSON2_CMCDMA_TCI; + } + + if (status & LOONGSON2_CMCDMA_HTI) + status &= ~LOONGSON2_CMCDMA_HTI; + + if (status & LOONGSON2_CMCDMA_TEI) { + dev_err(dev, "DMA Transform Error.\n"); + if (!(ccr & LOONGSON2_CMCDMA_CCR_EN)) + dev_err(dev, "Channel disabled by HW.\n"); + } + } + + return IRQ_HANDLED; +} + +static void loongson2_cmc_dma_issue_pending(struct dma_chan *chan) +{ + struct loongson2_cmc_dma_chan *lchan = to_lmdma_chan(chan); + + guard(spinlock_irqsave)(&lchan->vchan.lock); + + if (vchan_issue_pending(&lchan->vchan) && !lchan->desc) { + dev_dbg(chan2dev(lchan), "vchan %pK: issued\n", &lchan->vchan); + loongson2_cmc_dma_start_transfer(lchan); + } +} + +static int loongson2_cmc_dma_set_xfer_param(struct loongson2_cmc_dma_chan *lchan, + enum dma_transfer_direction direction, + enum dma_slave_buswidth *buswidth, u32 buf_len) +{ + struct dma_slave_config sconfig = lchan->dma_sconfig; + struct device *dev = chan2dev(lchan); + int dev_width; + u32 ccr; + + switch (direction) { + case DMA_MEM_TO_DEV: + dev_width = loongson2_cmc_dma_get_width(sconfig.dst_addr_width); + if (dev_width < 0) { + dev_err(dev, "DMA_MEM_TO_DEV bus width not supported\n"); + return dev_width; + } + lchan->chan_reg.cpar = sconfig.dst_addr; + ccr = LOONGSON2_CMCDMA_CCR_DIR; + *buswidth = sconfig.dst_addr_width; + break; + case DMA_DEV_TO_MEM: + dev_width = loongson2_cmc_dma_get_width(sconfig.src_addr_width); + if (dev_width < 0) { + dev_err(dev, "DMA_DEV_TO_MEM bus width not supported\n"); + return dev_width; + } + lchan->chan_reg.cpar = sconfig.src_addr; + ccr = LOONGSON2_CMCDMA_CCR_MINC; + *buswidth = sconfig.src_addr_width; + break; + default: + return -EINVAL; + } + + ccr |= FIELD_PREP(LOONGSON2_CMCDMA_CCR_PSIZE_MASK, dev_width) | + FIELD_PREP(LOONGSON2_CMCDMA_CCR_MSIZE_MASK, dev_width); + + /* Set DMA control register */ + lchan->chan_reg.ccr &= ~(LOONGSON2_CMCDMA_CCR_PSIZE_MASK | LOONGSON2_CMCDMA_CCR_MSIZE_MASK); + lchan->chan_reg.ccr |= ccr; + + return 0; +} + +static struct dma_async_tx_descriptor * +loongson2_cmc_dma_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, u32 sg_len, + enum dma_transfer_direction direction, + unsigned long flags, void *context) +{ + struct loongson2_cmc_dma_chan *lchan = to_lmdma_chan(chan); + struct loongson2_cmc_dma_desc *desc; + enum dma_slave_buswidth buswidth; + struct scatterlist *sg; + u32 num_items, i; + int ret; + + desc = kzalloc_flex(*desc, sg_req, sg_len, GFP_NOWAIT); + if (!desc) + return ERR_PTR(-ENOMEM); + + for_each_sg(sgl, sg, sg_len, i) { + ret = loongson2_cmc_dma_set_xfer_param(lchan, direction, &buswidth, sg_dma_len(sg)); + if (ret) + return ERR_PTR(ret); + + num_items = DIV_ROUND_UP(sg_dma_len(sg), buswidth); + if (num_items >= LOONSON2_CMCDMA_MAX_DATA_ITEMS) { + dev_err(chan2dev(lchan), "Number of items not supported\n"); + kfree(desc); + return ERR_PTR(-EINVAL); + } + + desc->sg_req[i].len = sg_dma_len(sg); + desc->sg_req[i].chan_reg.ccr = lchan->chan_reg.ccr; + desc->sg_req[i].chan_reg.cpar = lchan->chan_reg.cpar; + desc->sg_req[i].chan_reg.cmar = sg_dma_address(sg); + desc->sg_req[i].chan_reg.cndtr = num_items; + } + + desc->num_sgs = sg_len; + desc->cyclic = false; + + return vchan_tx_prep(&lchan->vchan, &desc->vdesc, flags); +} + +static struct dma_async_tx_descriptor * +loongson2_cmc_dma_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len, + size_t period_len, enum dma_transfer_direction direction, + unsigned long flags) +{ + struct loongson2_cmc_dma_chan *lchan = to_lmdma_chan(chan); + struct loongson2_cmc_dma_desc *desc; + enum dma_slave_buswidth buswidth; + u32 num_periods, num_items, i; + int ret; + + if (unlikely(buf_len % period_len)) + return ERR_PTR(-EINVAL); + + ret = loongson2_cmc_dma_set_xfer_param(lchan, direction, &buswidth, period_len); + if (ret) + return ERR_PTR(ret); + + num_items = DIV_ROUND_UP(period_len, buswidth); + if (num_items >= LOONSON2_CMCDMA_MAX_DATA_ITEMS) { + dev_err(chan2dev(lchan), "Number of items not supported\n"); + return ERR_PTR(-EINVAL); + } + + /* Enable Circular mode */ + if (buf_len == period_len) + lchan->chan_reg.ccr |= LOONGSON2_CMCDMA_CCR_CIRC; + + num_periods = DIV_ROUND_UP(buf_len, period_len); + desc = kzalloc_flex(*desc, sg_req, num_periods, GFP_NOWAIT); + if (!desc) + return ERR_PTR(-ENOMEM); + + for (i = 0; i < num_periods; i++) { + desc->sg_req[i].len = period_len; + desc->sg_req[i].chan_reg.ccr = lchan->chan_reg.ccr; + desc->sg_req[i].chan_reg.cpar = lchan->chan_reg.cpar; + desc->sg_req[i].chan_reg.cmar = buf_addr; + desc->sg_req[i].chan_reg.cndtr = num_items; + buf_addr += period_len; + } + + desc->num_sgs = num_periods; + desc->cyclic = true; + + return vchan_tx_prep(&lchan->vchan, &desc->vdesc, flags); +} + +static size_t loongson2_cmc_dma_desc_residue(struct loongson2_cmc_dma_chan *lchan, + struct loongson2_cmc_dma_desc *desc, u32 next_sg) +{ + struct loongson2_cmc_dma_dev *lddev = lmdma_get_dev(lchan); + u32 residue, width, ndtr, ccr, i; + + ccr = loongson2_cmc_dma_read(lddev, LOONGSON2_CMCDMA_CCR, lchan->id); + width = FIELD_GET(LOONGSON2_CMCDMA_CCR_PSIZE_MASK, ccr); + + ndtr = loongson2_cmc_dma_read(lddev, LOONGSON2_CMCDMA_CNDTR, lchan->id); + residue = ndtr << width; + + if (lchan->desc->cyclic && next_sg == 0) + return residue; + + for (i = next_sg; i < desc->num_sgs; i++) + residue += desc->sg_req[i].len; + + return residue; +} + +static enum dma_status loongson2_cmc_dma_tx_status(struct dma_chan *chan, dma_cookie_t cookie, + struct dma_tx_state *state) +{ + struct loongson2_cmc_dma_chan *lchan = to_lmdma_chan(chan); + struct virt_dma_desc *vdesc; + enum dma_status status; + + status = dma_cookie_status(chan, cookie, state); + if (status == DMA_COMPLETE || !state) + return status; + + scoped_guard(spinlock_irqsave, &lchan->vchan.lock) { + vdesc = vchan_find_desc(&lchan->vchan, cookie); + if (lchan->desc && cookie == lchan->desc->vdesc.tx.cookie) + state->residue = loongson2_cmc_dma_desc_residue(lchan, lchan->desc, + lchan->next_sg); + else if (vdesc) + state->residue = loongson2_cmc_dma_desc_residue(lchan, + to_lmdma_desc(vdesc), 0); + } + + return status; +} + +static void loongson2_cmc_dma_free_chan_resources(struct dma_chan *chan) +{ + vchan_free_chan_resources(to_virt_chan(chan)); +} + +static void loongson2_cmc_dma_desc_free(struct virt_dma_desc *vdesc) +{ + kfree(to_lmdma_desc(vdesc)); +} + +static bool loongson2_cmc_dma_acpi_filter(struct dma_chan *chan, void *param) +{ + struct loongson2_cmc_dma_chan *lchan = to_lmdma_chan(chan); + struct acpi_dma_spec *dma_spec = param; + + memset(&lchan->chan_reg, 0, sizeof(struct loongson2_cmc_dma_chan_reg)); + lchan->chan_reg.ccr = dma_spec->chan_id & LOONGSON2_CMCDMA_STREAM_MASK; + + return true; +} + +static int loongson2_cmc_dma_acpi_controller_register(struct loongson2_cmc_dma_dev *lddev) +{ + struct device *dev = lddev->ddev.dev; + struct acpi_dma_filter_info *info; + + if (!is_acpi_node(dev_fwnode(dev))) + return 0; + + info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL); + if (!info) + return -ENOMEM; + + dma_cap_zero(info->dma_cap); + info->dma_cap = lddev->ddev.cap_mask; + info->filter_fn = loongson2_cmc_dma_acpi_filter; + + return devm_acpi_dma_controller_register(dev, acpi_dma_simple_xlate, info); +} + +static struct dma_chan *loongson2_cmc_dma_of_xlate(struct of_phandle_args *dma_spec, + struct of_dma *ofdma) +{ + struct loongson2_cmc_dma_dev *lddev = ofdma->of_dma_data; + struct device *dev = lddev->ddev.dev; + struct loongson2_cmc_dma_chan *lchan; + struct dma_chan *chan; + + if (dma_spec->args_count < 2) + return ERR_PTR(-EINVAL); + + if (dma_spec->args[0] >= lddev->nr_channels) { + dev_err(dev, "Invalid channel id.\n"); + return ERR_PTR(-EINVAL); + } + + lchan = &lddev->chan[dma_spec->args[0]]; + chan = dma_get_slave_channel(&lchan->vchan.chan); + if (!chan) { + dev_err(dev, "No more channels available.\n"); + return ERR_PTR(-EINVAL); + } + + memset(&lchan->chan_reg, 0, sizeof(struct loongson2_cmc_dma_chan_reg)); + lchan->chan_reg.ccr = dma_spec->args[1] & LOONGSON2_CMCDMA_STREAM_MASK; + + return chan; +} + +static int loongson2_cmc_dma_of_controller_register(struct loongson2_cmc_dma_dev *lddev) +{ + struct device *dev = lddev->ddev.dev; + + if (!is_of_node(dev_fwnode(dev))) + return 0; + + return of_dma_controller_register(dev->of_node, loongson2_cmc_dma_of_xlate, lddev); +} + +static int loongson2_cmc_dma_probe(struct platform_device *pdev) +{ + const struct loongson2_cmc_dma_config *config; + struct loongson2_cmc_dma_chan *lchan; + struct loongson2_cmc_dma_dev *lddev; + struct device *dev = &pdev->dev; + struct dma_device *ddev; + u32 nr_chans, i; + int ret; + + config = (const struct loongson2_cmc_dma_config *)device_get_match_data(dev); + if (!config) + return -EINVAL; + + ret = device_property_read_u32(dev, "dma-channels", &nr_chans); + if (ret || nr_chans > config->max_channels) { + dev_err(dev, "missing or invalid dma-channels property\n"); + nr_chans = config->max_channels; + } + + lddev = devm_kzalloc(dev, struct_size(lddev, chan, nr_chans), GFP_KERNEL); + if (!lddev) + return -ENOMEM; + + lddev->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(lddev->base)) + return PTR_ERR(lddev->base); + + platform_set_drvdata(pdev, lddev); + lddev->nr_channels = nr_chans; + lddev->chan_reg_offset = config->chan_reg_offset; + + lddev->dma_clk = devm_clk_get_optional_enabled(dev, NULL); + if (IS_ERR(lddev->dma_clk)) + return dev_err_probe(dev, PTR_ERR(lddev->dma_clk), "Failed to get dma clock\n"); + + ddev = &lddev->ddev; + ddev->dev = dev; + + dma_cap_zero(ddev->cap_mask); + dma_cap_set(DMA_SLAVE, ddev->cap_mask); + dma_cap_set(DMA_PRIVATE, ddev->cap_mask); + dma_cap_set(DMA_CYCLIC, ddev->cap_mask); + + ddev->device_free_chan_resources = loongson2_cmc_dma_free_chan_resources; + ddev->device_config = loongson2_cmc_dma_slave_config; + ddev->device_prep_slave_sg = loongson2_cmc_dma_prep_slave_sg; + ddev->device_prep_dma_cyclic = loongson2_cmc_dma_prep_dma_cyclic; + ddev->device_issue_pending = loongson2_cmc_dma_issue_pending; + ddev->device_synchronize = loongson2_cmc_dma_synchronize; + ddev->device_tx_status = loongson2_cmc_dma_tx_status; + ddev->device_terminate_all = loongson2_cmc_dma_terminate_all; + + ddev->max_sg_burst = LOONSON2_CMCDMA_MAX_DATA_ITEMS; + ddev->src_addr_widths = LOONGSON2_CMCDMA_BUSWIDTHS; + ddev->dst_addr_widths = LOONGSON2_CMCDMA_BUSWIDTHS; + ddev->directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV); + INIT_LIST_HEAD(&ddev->channels); + + for (i = 0; i < nr_chans; i++) { + lchan = &lddev->chan[i]; + + lchan->id = i; + lchan->vchan.desc_free = loongson2_cmc_dma_desc_free; + vchan_init(&lchan->vchan, ddev); + } + + ret = dmaenginem_async_device_register(ddev); + if (ret) + return dev_err_probe(dev, ret, "Failed to register DMA engine device.\n"); + + for (i = 0; i < nr_chans; i++) { + lchan = &lddev->chan[i]; + + lchan->irq = platform_get_irq(pdev, i); + if (lchan->irq < 0) + return lchan->irq; + + ret = devm_request_irq(dev, lchan->irq, loongson2_cmc_dma_chan_irq, IRQF_SHARED, + dev_name(chan2dev(lchan)), lchan); + if (ret) + return ret; + } + + ret = loongson2_cmc_dma_acpi_controller_register(lddev); + if (ret) + return dev_err_probe(dev, ret, "Failed to register dma controller with ACPI.\n"); + + ret = loongson2_cmc_dma_of_controller_register(lddev); + if (ret) + return dev_err_probe(dev, ret, "Failed to register dma controller with FDT.\n"); + + dev_info(dev, "Loongson-2 Multi-Channel DMA Controller registered successfully.\n"); + + return 0; +} + +static void loongson2_cmc_dma_remove(struct platform_device *pdev) +{ + of_dma_controller_free(pdev->dev.of_node); +} + +static const struct of_device_id loongson2_cmc_dma_of_match[] = { + { .compatible = "loongson,ls2k0300-dma", .data = &ls2k0300_cmc_dma_config }, + { .compatible = "loongson,ls2k3000-dma", .data = &ls2k3000_cmc_dma_config }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, loongson2_cmc_dma_of_match); + +static const struct acpi_device_id loongson2_cmc_dma_acpi_match[] = { + { "LOON0014", .driver_data = (kernel_ulong_t)&ls2k3000_cmc_dma_config }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(acpi, loongson2_cmc_dma_acpi_match); + +static struct platform_driver loongson2_cmc_dma_driver = { + .driver = { + .name = "loongson2-apb-cmc-dma", + .of_match_table = loongson2_cmc_dma_of_match, + .acpi_match_table = loongson2_cmc_dma_acpi_match, + }, + .probe = loongson2_cmc_dma_probe, + .remove = loongson2_cmc_dma_remove, +}; +module_platform_driver(loongson2_cmc_dma_driver); + +MODULE_DESCRIPTION("Loongson-2 Chain Multi-Channel DMA Controller driver"); +MODULE_AUTHOR("Loongson Technology Corporation Limited"); +MODULE_LICENSE("GPL"); diff --git a/drivers/dma/loongson/loongson2-apb-dma.c b/drivers/dma/loongson/loongson2-apb-dma.c new file mode 100644 index 000000000..aceb069e7 --- /dev/null +++ b/drivers/dma/loongson/loongson2-apb-dma.c @@ -0,0 +1,686 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Driver for the Loongson-2 APB DMA Controller + * + * Copyright (C) 2017-2023 Loongson Corporation + */ + +#include <linux/clk.h> +#include <linux/dma-mapping.h> +#include <linux/dmapool.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/io-64-nonatomic-lo-hi.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_dma.h> +#include <linux/platform_device.h> +#include <linux/slab.h> + +#include "../dmaengine.h" +#include "../virt-dma.h" + +/* Global Configuration Register */ +#define LDMA_ORDER_ERG 0x0 + +/* Bitfield definitions */ + +/* Bitfields in Global Configuration Register */ +#define LDMA_64BIT_EN BIT(0) /* 1: 64 bit support */ +#define LDMA_UNCOHERENT_EN BIT(1) /* 0: cache, 1: uncache */ +#define LDMA_ASK_VALID BIT(2) +#define LDMA_START BIT(3) /* DMA start operation */ +#define LDMA_STOP BIT(4) /* DMA stop operation */ +#define LDMA_CONFIG_MASK GENMASK_ULL(4, 0) /* DMA controller config bits mask */ + +/* Bitfields in ndesc_addr field of HW descriptor */ +#define LDMA_DESC_EN BIT(0) /*1: The next descriptor is valid */ +#define LDMA_DESC_ADDR_LOW GENMASK(31, 1) + +/* Bitfields in cmd field of HW descriptor */ +#define LDMA_INT BIT(1) /* Enable DMA interrupts */ +#define LDMA_DATA_DIRECTION BIT(12) /* 1: write to device, 0: read from device */ + +#define LDMA_SLAVE_BUSWIDTHS (BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) | \ + BIT(DMA_SLAVE_BUSWIDTH_8_BYTES)) + +#define LDMA_MAX_TRANS_LEN U32_MAX + +/*-- descriptors -----------------------------------------------------*/ + +/* + * struct ls2x_dma_hw_desc - DMA HW descriptor + * @ndesc_addr: the next descriptor low address. + * @mem_addr: memory low address. + * @apb_addr: device buffer address. + * @len: length of a piece of carried content, in words. + * @step_len: length between two moved memory data blocks. + * @step_times: number of blocks to be carried in a single DMA operation. + * @cmd: descriptor command or state. + * @stats: DMA status. + * @high_ndesc_addr: the next descriptor high address. + * @high_mem_addr: memory high address. + * @reserved: reserved + */ +struct ls2x_dma_hw_desc { + u32 ndesc_addr; + u32 mem_addr; + u32 apb_addr; + u32 len; + u32 step_len; + u32 step_times; + u32 cmd; + u32 stats; + u32 high_ndesc_addr; + u32 high_mem_addr; + u32 reserved[2]; +} __packed; + +/* + * struct ls2x_dma_sg - ls2x dma scatter gather entry + * @hw: the pointer to DMA HW descriptor. + * @llp: physical address of the DMA HW descriptor. + * @phys: destination or source address(mem). + * @len: number of Bytes to read. + */ +struct ls2x_dma_sg { + struct ls2x_dma_hw_desc *hw; + dma_addr_t llp; + dma_addr_t phys; + u32 len; +}; + +/* + * struct ls2x_dma_desc - software descriptor + * @vdesc: pointer to the virtual dma descriptor. + * @cyclic: flag to dma cyclic + * @burst_size: burst size of transaction, in words. + * @desc_num: number of sg entries. + * @direction: transfer direction, to or from device. + * @status: dma controller status. + * @sg: array of sgs. + */ +struct ls2x_dma_desc { + struct virt_dma_desc vdesc; + bool cyclic; + size_t burst_size; + u32 desc_num; + enum dma_transfer_direction direction; + enum dma_status status; + struct ls2x_dma_sg sg[] __counted_by(desc_num); +}; + +/*-- Channels --------------------------------------------------------*/ + +/* + * struct ls2x_dma_chan - internal representation of an LS2X APB DMA channel + * @vchan: virtual dma channel entry. + * @desc: pointer to the ls2x sw dma descriptor. + * @pool: hw desc table + * @irq: irq line + * @sconfig: configuration for slave transfers, passed via .device_config + */ +struct ls2x_dma_chan { + struct virt_dma_chan vchan; + struct ls2x_dma_desc *desc; + void *pool; + int irq; + struct dma_slave_config sconfig; +}; + +/*-- Controller ------------------------------------------------------*/ + +/* + * struct ls2x_dma_priv - LS2X APB DMAC specific information + * @ddev: dmaengine dma_device object members + * @dma_clk: DMAC clock source + * @regs: memory mapped register base + * @lchan: channel to store ls2x_dma_chan structures + */ +struct ls2x_dma_priv { + struct dma_device ddev; + struct clk *dma_clk; + void __iomem *regs; + struct ls2x_dma_chan lchan; +}; + +/*-- Helper functions ------------------------------------------------*/ + +static inline struct ls2x_dma_desc *to_ldma_desc(struct virt_dma_desc *vdesc) +{ + return container_of(vdesc, struct ls2x_dma_desc, vdesc); +} + +static inline struct ls2x_dma_chan *to_ldma_chan(struct dma_chan *chan) +{ + return container_of(chan, struct ls2x_dma_chan, vchan.chan); +} + +static inline struct ls2x_dma_priv *to_ldma_priv(struct dma_device *ddev) +{ + return container_of(ddev, struct ls2x_dma_priv, ddev); +} + +static struct device *chan2dev(struct dma_chan *chan) +{ + return &chan->dev->device; +} + +static void ls2x_dma_desc_free(struct virt_dma_desc *vdesc) +{ + struct ls2x_dma_chan *lchan = to_ldma_chan(vdesc->tx.chan); + struct ls2x_dma_desc *desc = to_ldma_desc(vdesc); + int i; + + for (i = 0; i < desc->desc_num; i++) { + if (desc->sg[i].hw) + dma_pool_free(lchan->pool, desc->sg[i].hw, + desc->sg[i].llp); + } + + kfree(desc); +} + +static void ls2x_dma_write_cmd(struct ls2x_dma_chan *lchan, bool cmd) +{ + struct ls2x_dma_priv *priv = to_ldma_priv(lchan->vchan.chan.device); + u64 val; + + val = lo_hi_readq(priv->regs + LDMA_ORDER_ERG) & ~LDMA_CONFIG_MASK; + val |= LDMA_64BIT_EN | cmd; + lo_hi_writeq(val, priv->regs + LDMA_ORDER_ERG); +} + +static void ls2x_dma_start_transfer(struct ls2x_dma_chan *lchan) +{ + struct ls2x_dma_priv *priv = to_ldma_priv(lchan->vchan.chan.device); + struct ls2x_dma_sg *ldma_sg; + struct virt_dma_desc *vdesc; + u64 val; + + /* Get the next descriptor */ + vdesc = vchan_next_desc(&lchan->vchan); + if (!vdesc) { + lchan->desc = NULL; + return; + } + + list_del(&vdesc->node); + lchan->desc = to_ldma_desc(vdesc); + ldma_sg = &lchan->desc->sg[0]; + + /* Start DMA */ + lo_hi_writeq(0, priv->regs + LDMA_ORDER_ERG); + val = (ldma_sg->llp & ~LDMA_CONFIG_MASK) | LDMA_64BIT_EN | LDMA_START; + lo_hi_writeq(val, priv->regs + LDMA_ORDER_ERG); +} + +static size_t ls2x_dmac_detect_burst(struct ls2x_dma_chan *lchan) +{ + u32 maxburst, buswidth; + + /* Reject definitely invalid configurations */ + if ((lchan->sconfig.src_addr_width & LDMA_SLAVE_BUSWIDTHS) && + (lchan->sconfig.dst_addr_width & LDMA_SLAVE_BUSWIDTHS)) + return 0; + + if (lchan->sconfig.direction == DMA_MEM_TO_DEV) { + maxburst = lchan->sconfig.dst_maxburst; + buswidth = lchan->sconfig.dst_addr_width; + } else { + maxburst = lchan->sconfig.src_maxburst; + buswidth = lchan->sconfig.src_addr_width; + } + + /* If maxburst is zero, fallback to LDMA_MAX_TRANS_LEN */ + return maxburst ? (maxburst * buswidth) >> 2 : LDMA_MAX_TRANS_LEN; +} + +static void ls2x_dma_fill_desc(struct ls2x_dma_chan *lchan, u32 sg_index, + struct ls2x_dma_desc *desc) +{ + struct ls2x_dma_sg *ldma_sg = &desc->sg[sg_index]; + u32 num_segments, segment_size; + + if (desc->direction == DMA_MEM_TO_DEV) { + ldma_sg->hw->cmd = LDMA_INT | LDMA_DATA_DIRECTION; + ldma_sg->hw->apb_addr = lchan->sconfig.dst_addr; + } else { + ldma_sg->hw->cmd = LDMA_INT; + ldma_sg->hw->apb_addr = lchan->sconfig.src_addr; + } + + ldma_sg->hw->mem_addr = lower_32_bits(ldma_sg->phys); + ldma_sg->hw->high_mem_addr = upper_32_bits(ldma_sg->phys); + + /* Split into multiple equally sized segments if necessary */ + num_segments = DIV_ROUND_UP((ldma_sg->len + 3) >> 2, desc->burst_size); + segment_size = DIV_ROUND_UP((ldma_sg->len + 3) >> 2, num_segments); + + /* Word count register takes input in words */ + ldma_sg->hw->len = segment_size; + ldma_sg->hw->step_times = num_segments; + ldma_sg->hw->step_len = 0; + + /* lets make a link list */ + if (sg_index) { + desc->sg[sg_index - 1].hw->ndesc_addr = ldma_sg->llp | LDMA_DESC_EN; + desc->sg[sg_index - 1].hw->high_ndesc_addr = upper_32_bits(ldma_sg->llp); + } +} + +/*-- DMA Engine API --------------------------------------------------*/ + +/* + * ls2x_dma_alloc_chan_resources - allocate resources for DMA channel + * @chan: allocate descriptor resources for this channel + * + * return - the number of allocated descriptors + */ +static int ls2x_dma_alloc_chan_resources(struct dma_chan *chan) +{ + struct ls2x_dma_chan *lchan = to_ldma_chan(chan); + + /* Create a pool of consistent memory blocks for hardware descriptors */ + lchan->pool = dma_pool_create(dev_name(chan2dev(chan)), + chan->device->dev, PAGE_SIZE, + __alignof__(struct ls2x_dma_hw_desc), 0); + if (!lchan->pool) { + dev_err(chan2dev(chan), "No memory for descriptors\n"); + return -ENOMEM; + } + + return 1; +} + +/* + * ls2x_dma_free_chan_resources - free all channel resources + * @chan: DMA channel + */ +static void ls2x_dma_free_chan_resources(struct dma_chan *chan) +{ + struct ls2x_dma_chan *lchan = to_ldma_chan(chan); + + vchan_free_chan_resources(to_virt_chan(chan)); + dma_pool_destroy(lchan->pool); + lchan->pool = NULL; +} + +/* + * ls2x_dma_prep_slave_sg - prepare descriptors for a DMA_SLAVE transaction + * @chan: DMA channel + * @sgl: scatterlist to transfer to/from + * @sg_len: number of entries in @scatterlist + * @direction: DMA direction + * @flags: tx descriptor status flags + * @context: transaction context (ignored) + * + * Return: Async transaction descriptor on success and NULL on failure + */ +static struct dma_async_tx_descriptor * +ls2x_dma_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, + u32 sg_len, enum dma_transfer_direction direction, + unsigned long flags, void *context) +{ + struct ls2x_dma_chan *lchan = to_ldma_chan(chan); + struct ls2x_dma_desc *desc; + struct scatterlist *sg; + size_t burst_size; + int i; + + if (unlikely(!sg_len || !is_slave_direction(direction))) + return NULL; + + burst_size = ls2x_dmac_detect_burst(lchan); + if (!burst_size) + return NULL; + + desc = kzalloc_flex(*desc, sg, sg_len, GFP_NOWAIT); + if (!desc) + return NULL; + + desc->desc_num = sg_len; + desc->direction = direction; + desc->burst_size = burst_size; + + for_each_sg(sgl, sg, sg_len, i) { + struct ls2x_dma_sg *ldma_sg = &desc->sg[i]; + + /* Allocate DMA capable memory for hardware descriptor */ + ldma_sg->hw = dma_pool_alloc(lchan->pool, GFP_NOWAIT, &ldma_sg->llp); + if (!ldma_sg->hw) { + desc->desc_num = i; + ls2x_dma_desc_free(&desc->vdesc); + return NULL; + } + + ldma_sg->phys = sg_dma_address(sg); + ldma_sg->len = sg_dma_len(sg); + + ls2x_dma_fill_desc(lchan, i, desc); + } + + /* Setting the last descriptor enable bit */ + desc->sg[sg_len - 1].hw->ndesc_addr &= ~LDMA_DESC_EN; + desc->status = DMA_IN_PROGRESS; + + return vchan_tx_prep(&lchan->vchan, &desc->vdesc, flags); +} + +/* + * ls2x_dma_prep_dma_cyclic - prepare the cyclic DMA transfer + * @chan: the DMA channel to prepare + * @buf_addr: physical DMA address where the buffer starts + * @buf_len: total number of bytes for the entire buffer + * @period_len: number of bytes for each period + * @direction: transfer direction, to or from device + * @flags: tx descriptor status flags + * + * Return: Async transaction descriptor on success and NULL on failure + */ +static struct dma_async_tx_descriptor * +ls2x_dma_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len, + size_t period_len, enum dma_transfer_direction direction, + unsigned long flags) +{ + struct ls2x_dma_chan *lchan = to_ldma_chan(chan); + struct ls2x_dma_desc *desc; + size_t burst_size; + u32 num_periods; + int i; + + if (unlikely(!buf_len || !period_len)) + return NULL; + + if (unlikely(!is_slave_direction(direction))) + return NULL; + + burst_size = ls2x_dmac_detect_burst(lchan); + if (!burst_size) + return NULL; + + num_periods = buf_len / period_len; + desc = kzalloc_flex(*desc, sg, num_periods, GFP_NOWAIT); + if (!desc) + return NULL; + + desc->desc_num = num_periods; + desc->direction = direction; + desc->burst_size = burst_size; + + /* Build cyclic linked list */ + for (i = 0; i < num_periods; i++) { + struct ls2x_dma_sg *ldma_sg = &desc->sg[i]; + + /* Allocate DMA capable memory for hardware descriptor */ + ldma_sg->hw = dma_pool_alloc(lchan->pool, GFP_NOWAIT, &ldma_sg->llp); + if (!ldma_sg->hw) { + desc->desc_num = i; + ls2x_dma_desc_free(&desc->vdesc); + return NULL; + } + + ldma_sg->phys = buf_addr + period_len * i; + ldma_sg->len = period_len; + + ls2x_dma_fill_desc(lchan, i, desc); + } + + /* Lets make a cyclic list */ + desc->sg[num_periods - 1].hw->ndesc_addr = desc->sg[0].llp | LDMA_DESC_EN; + desc->sg[num_periods - 1].hw->high_ndesc_addr = upper_32_bits(desc->sg[0].llp); + desc->cyclic = true; + desc->status = DMA_IN_PROGRESS; + + return vchan_tx_prep(&lchan->vchan, &desc->vdesc, flags); +} + +/* + * ls2x_slave_config - set slave configuration for channel + * @chan: dma channel + * @cfg: slave configuration + * + * Sets slave configuration for channel + */ +static int ls2x_dma_slave_config(struct dma_chan *chan, + struct dma_slave_config *config) +{ + struct ls2x_dma_chan *lchan = to_ldma_chan(chan); + + memcpy(&lchan->sconfig, config, sizeof(*config)); + return 0; +} + +/* + * ls2x_dma_issue_pending - push pending transactions to the hardware + * @chan: channel + * + * When this function is called, all pending transactions are pushed to the + * hardware and executed. + */ +static void ls2x_dma_issue_pending(struct dma_chan *chan) +{ + struct ls2x_dma_chan *lchan = to_ldma_chan(chan); + + guard(spinlock_irqsave)(&lchan->vchan.lock); + + if (vchan_issue_pending(&lchan->vchan) && !lchan->desc) + ls2x_dma_start_transfer(lchan); +} + +/* + * ls2x_dma_terminate_all - terminate all transactions + * @chan: channel + * + * Stops all DMA transactions. + */ +static int ls2x_dma_terminate_all(struct dma_chan *chan) +{ + struct ls2x_dma_chan *lchan = to_ldma_chan(chan); + LIST_HEAD(head); + + scoped_guard(spinlock_irqsave, &lchan->vchan.lock) { + /* Setting stop cmd */ + ls2x_dma_write_cmd(lchan, LDMA_STOP); + if (lchan->desc) { + vchan_terminate_vdesc(&lchan->desc->vdesc); + lchan->desc = NULL; + } + + vchan_get_all_descriptors(&lchan->vchan, &head); + } + + vchan_dma_desc_free_list(&lchan->vchan, &head); + return 0; +} + +/* + * ls2x_dma_synchronize - Synchronizes the termination of transfers to the + * current context. + * @chan: channel + */ +static void ls2x_dma_synchronize(struct dma_chan *chan) +{ + struct ls2x_dma_chan *lchan = to_ldma_chan(chan); + + vchan_synchronize(&lchan->vchan); +} + +static int ls2x_dma_pause(struct dma_chan *chan) +{ + struct ls2x_dma_chan *lchan = to_ldma_chan(chan); + + guard(spinlock_irqsave)(&lchan->vchan.lock); + + if (lchan->desc && lchan->desc->status == DMA_IN_PROGRESS) { + ls2x_dma_write_cmd(lchan, LDMA_STOP); + lchan->desc->status = DMA_PAUSED; + } + + return 0; +} + +static int ls2x_dma_resume(struct dma_chan *chan) +{ + struct ls2x_dma_chan *lchan = to_ldma_chan(chan); + + guard(spinlock_irqsave)(&lchan->vchan.lock); + + if (lchan->desc && lchan->desc->status == DMA_PAUSED) { + lchan->desc->status = DMA_IN_PROGRESS; + ls2x_dma_write_cmd(lchan, LDMA_START); + } + + return 0; +} + +/* + * ls2x_dma_isr - LS2X DMA Interrupt handler + * @irq: IRQ number + * @dev_id: Pointer to ls2x_dma_chan + * + * Return: IRQ_HANDLED/IRQ_NONE + */ +static irqreturn_t ls2x_dma_isr(int irq, void *dev_id) +{ + struct ls2x_dma_chan *lchan = dev_id; + struct ls2x_dma_desc *desc; + + scoped_guard(spinlock, &lchan->vchan.lock) { + desc = lchan->desc; + if (desc) { + if (desc->cyclic) { + vchan_cyclic_callback(&desc->vdesc); + } else { + desc->status = DMA_COMPLETE; + vchan_cookie_complete(&desc->vdesc); + ls2x_dma_start_transfer(lchan); + } + + /* ls2x_dma_start_transfer() updates lchan->desc */ + if (!lchan->desc) + ls2x_dma_write_cmd(lchan, LDMA_STOP); + } + } + + return IRQ_HANDLED; +} + +static int ls2x_dma_chan_init(struct platform_device *pdev, + struct ls2x_dma_priv *priv) +{ + struct ls2x_dma_chan *lchan = &priv->lchan; + struct device *dev = &pdev->dev; + int ret; + + lchan->irq = platform_get_irq(pdev, 0); + if (lchan->irq < 0) + return lchan->irq; + + ret = devm_request_irq(dev, lchan->irq, ls2x_dma_isr, IRQF_TRIGGER_RISING, + dev_name(&pdev->dev), lchan); + if (ret) + return ret; + + /* Initialize channels related values */ + INIT_LIST_HEAD(&priv->ddev.channels); + lchan->vchan.desc_free = ls2x_dma_desc_free; + vchan_init(&lchan->vchan, &priv->ddev); + + return 0; +} + +/* + * ls2x_dma_probe - Driver probe function + * @pdev: Pointer to the platform_device structure + * + * Return: '0' on success and failure value on error + */ +static int ls2x_dma_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct ls2x_dma_priv *priv; + struct dma_device *ddev; + int ret; + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->regs = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(priv->regs)) + return dev_err_probe(dev, PTR_ERR(priv->regs), + "devm_platform_ioremap_resource failed.\n"); + + priv->dma_clk = devm_clk_get_enabled(dev, NULL); + if (IS_ERR(priv->dma_clk)) + return dev_err_probe(dev, PTR_ERR(priv->dma_clk), "Couldn't start the clock.\n"); + + ret = ls2x_dma_chan_init(pdev, priv); + if (ret) + return ret; + + ddev = &priv->ddev; + ddev->dev = dev; + dma_cap_zero(ddev->cap_mask); + dma_cap_set(DMA_SLAVE, ddev->cap_mask); + dma_cap_set(DMA_CYCLIC, ddev->cap_mask); + + ddev->device_alloc_chan_resources = ls2x_dma_alloc_chan_resources; + ddev->device_free_chan_resources = ls2x_dma_free_chan_resources; + ddev->device_tx_status = dma_cookie_status; + ddev->device_issue_pending = ls2x_dma_issue_pending; + ddev->device_prep_slave_sg = ls2x_dma_prep_slave_sg; + ddev->device_prep_dma_cyclic = ls2x_dma_prep_dma_cyclic; + ddev->device_config = ls2x_dma_slave_config; + ddev->device_terminate_all = ls2x_dma_terminate_all; + ddev->device_synchronize = ls2x_dma_synchronize; + ddev->device_pause = ls2x_dma_pause; + ddev->device_resume = ls2x_dma_resume; + + ddev->src_addr_widths = LDMA_SLAVE_BUSWIDTHS; + ddev->dst_addr_widths = LDMA_SLAVE_BUSWIDTHS; + ddev->directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV); + + ret = dmaenginem_async_device_register(&priv->ddev); + if (ret < 0) + return dev_err_probe(dev, ret, "Failed to register DMA engine device.\n"); + + ret = of_dma_controller_register(dev->of_node, of_dma_xlate_by_chan_id, priv); + if (ret < 0) + return dev_err_probe(dev, ret, "Failed to register dma controller.\n"); + + platform_set_drvdata(pdev, priv); + + dev_info(dev, "Loongson LS2X APB DMA driver registered successfully.\n"); + return 0; +} + +/* + * ls2x_dma_remove - Driver remove function + * @pdev: Pointer to the platform_device structure + */ +static void ls2x_dma_remove(struct platform_device *pdev) +{ + of_dma_controller_free(pdev->dev.of_node); +} + +static const struct of_device_id ls2x_dma_of_match_table[] = { + { .compatible = "loongson,ls2k1000-apbdma" }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, ls2x_dma_of_match_table); + +static struct platform_driver ls2x_dmac_driver = { + .probe = ls2x_dma_probe, + .remove = ls2x_dma_remove, + .driver = { + .name = "ls2x-apbdma", + .of_match_table = ls2x_dma_of_match_table, + }, +}; +module_platform_driver(ls2x_dmac_driver); + +MODULE_DESCRIPTION("Loongson-2 APB DMA Controller driver"); +MODULE_AUTHOR("Loongson Technology Corporation Limited"); +MODULE_LICENSE("GPL"); |