From 9cc63f8bcd560c760d0b12e15bba8f81c86237cf Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Fri, 14 Aug 2026 15:43:51 -0700 Subject: Merge branches 'expcb.2026.07.24a', 'misc.2026.07.30a', 'rcu-tasks.2026.07.30a', 'srcu.2026.08.11a' and 'torture.2026.08.14a' into HEAD Changes: Make expedited grace periods expedite normal RCU callbacks Miscellaneous fixes: * Improve diagnostic output with character task states. * Mark accesses to inform KCSAN of concurrency design. * Move from kmalloc() to kmalloc_obj(). * Documentation updates. * Improve handling of RCU deferred quiescent states. * Clean up unused function arguments and structure fields. * Reduce show_rcu_gp_kthreads() stack space. Tasks RCU updates: * Clean up after SRCU re-implementation of Tasks Trace RCU. * Mark accesses to inform KCSAN of concurrency design. * Add ->lazy_timer status to diagnostic output. * Remove an unnecessary memory barrier. * Fix a data race, courtesy of KCSAN. * Documentation updates. * Convert cond_resched_tasks_rcu_qs() from macro to static inline function. SRCU updates: * Add Rust helpers for SRCU. * Avoid losing queued work at cleanup_srcu_struct() time. Torture-test updates: * Preparation work for immediate RCU priority deboosting. * Test RCU readers from real interrupt handlers (as opposed to softirq). * Simplify code through use of cpumask_next_wrap(). * Improve diagnostic output with character task states. * Add rcutorture.nwriters parameter to allow lightweight stall testing, and rcutorture.stall_only to make doing so easier. * Test an RCU Tasks Trace grace period implying an RCU grace period. * Make RCU Tasks Trace torturing track reader batches. * Fix a data race, courtesy of KCSAN. * Plug a shuffle_tmp_mask memory leak on kthread spawn failure. --- drivers/mcb/mcb-parse.c | 253 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 253 insertions(+) create mode 100644 drivers/mcb/mcb-parse.c (limited to 'drivers/mcb/mcb-parse.c') diff --git a/drivers/mcb/mcb-parse.c b/drivers/mcb/mcb-parse.c new file mode 100644 index 000000000..7e09a0ea8 --- /dev/null +++ b/drivers/mcb/mcb-parse.c @@ -0,0 +1,253 @@ +// SPDX-License-Identifier: GPL-2.0-only +#include +#include +#include +#include +#include +#include + +#include "mcb-internal.h" + +#define for_each_chameleon_cell(dtype, p) \ + for ((dtype) = get_next_dtype((p)); \ + (dtype) != CHAMELEON_DTYPE_END; \ + (dtype) = get_next_dtype((p))) + +static inline uint32_t get_next_dtype(void __iomem *p) +{ + uint32_t dtype; + + dtype = readl(p); + return dtype >> 28; +} + +static int chameleon_parse_bdd(struct mcb_bus *bus, + struct chameleon_bar *cb, + void __iomem *base) +{ + return 0; +} + +static int chameleon_parse_gdd(struct mcb_bus *bus, + struct chameleon_bar *cb, + void __iomem *base, int bar_count) +{ + struct chameleon_gdd __iomem *gdd = + (struct chameleon_gdd __iomem *) base; + struct mcb_device *mdev; + u32 dev_mapbase; + u32 offset; + u32 size; + int ret; + __le32 reg1; + __le32 reg2; + + mdev = mcb_alloc_dev(bus); + if (!mdev) + return -ENOMEM; + + reg1 = readl(&gdd->reg1); + reg2 = readl(&gdd->reg2); + offset = readl(&gdd->offset); + size = readl(&gdd->size); + + mdev->id = GDD_DEV(reg1); + mdev->rev = GDD_REV(reg1); + mdev->var = GDD_VAR(reg1); + mdev->bar = GDD_BAR(reg2); + mdev->group = GDD_GRP(reg2); + mdev->inst = GDD_INS(reg2); + + /* + * If the BAR is missing, dev_mapbase is zero, or if the + * device is IO mapped we just print a warning and go on with the + * next device, instead of completely stop the gdd parser + */ + if (mdev->bar > bar_count - 1) { + pr_info("No BAR for 16z%03d\n", mdev->id); + ret = 0; + goto err; + } + + dev_mapbase = cb[mdev->bar].addr; + if (!dev_mapbase) { + pr_info("BAR not assigned for 16z%03d\n", mdev->id); + ret = 0; + goto err; + } + + if (dev_mapbase & 0x01) { + pr_info("IO mapped Device (16z%03d) not yet supported\n", + mdev->id); + ret = 0; + goto err; + } + + pr_debug("Found a 16z%03d\n", mdev->id); + + mdev->irq.start = GDD_IRQ(reg1); + mdev->irq.end = GDD_IRQ(reg1); + mdev->irq.flags = IORESOURCE_IRQ; + + mdev->mem.start = dev_mapbase + offset; + + mdev->mem.end = mdev->mem.start + size - 1; + mdev->mem.flags = IORESOURCE_MEM; + + ret = mcb_device_register(bus, mdev); + if (ret < 0) + return ret; + + return 0; + +err: + mcb_free_dev(mdev); + + return ret; +} + +static void chameleon_parse_bar(void __iomem *base, + struct chameleon_bar *cb, int bar_count) +{ + char __iomem *p = base; + int i; + + /* skip reg1 */ + p += sizeof(__le32); + + for (i = 0; i < bar_count; i++) { + cb[i].addr = readl(p); + cb[i].size = readl(p + 4); + + p += sizeof(struct chameleon_bar); + } +} + +static int chameleon_get_bar(void __iomem **base, phys_addr_t mapbase, + struct chameleon_bar **cb) +{ + struct chameleon_bar *c; + int bar_count; + __le32 reg; + u32 dtype; + + /* + * For those devices which are not connected + * to the PCI Bus (e.g. LPC) there is a bar + * descriptor located directly after the + * chameleon header. This header is comparable + * to a PCI header. + */ + dtype = get_next_dtype(*base); + if (dtype == CHAMELEON_DTYPE_BAR) { + reg = readl(*base); + + bar_count = BAR_CNT(reg); + if (bar_count <= 0 || bar_count > CHAMELEON_BAR_MAX) + return -ENODEV; + + c = kzalloc_objs(struct chameleon_bar, bar_count); + if (!c) + return -ENOMEM; + + chameleon_parse_bar(*base, c, bar_count); + *base += BAR_DESC_SIZE(bar_count); + } else { + c = kzalloc_obj(struct chameleon_bar); + if (!c) + return -ENOMEM; + + bar_count = 1; + c->addr = mapbase; + } + + *cb = c; + + return bar_count; +} + +int chameleon_parse_cells(struct mcb_bus *bus, phys_addr_t mapbase, + void __iomem *base) +{ + struct chameleon_fpga_header *header; + struct chameleon_bar *cb; + void __iomem *p = base; + int num_cells = 0; + uint32_t dtype; + int bar_count; + int ret; + u32 hsize; + u32 table_size; + + hsize = sizeof(struct chameleon_fpga_header); + + header = kzalloc(hsize, GFP_KERNEL); + if (!header) + return -ENOMEM; + + /* Extract header information */ + memcpy_fromio(header, p, hsize); + /* We only support chameleon v2 at the moment */ + header->magic = le16_to_cpu(header->magic); + if (header->magic != CHAMELEONV2_MAGIC) { + pr_err("Unsupported chameleon version 0x%x\n", + header->magic); + ret = -ENODEV; + goto free_header; + } + p += hsize; + + bus->revision = header->revision; + bus->model = header->model; + bus->minor = header->minor; + snprintf(bus->name, CHAMELEON_FILENAME_LEN + 1, "%s", + header->filename); + + bar_count = chameleon_get_bar(&p, mapbase, &cb); + if (bar_count < 0) { + ret = bar_count; + goto free_header; + } + + for_each_chameleon_cell(dtype, p) { + switch (dtype) { + case CHAMELEON_DTYPE_GENERAL: + ret = chameleon_parse_gdd(bus, cb, p, bar_count); + if (ret < 0) + goto free_bar; + p += sizeof(struct chameleon_gdd); + break; + case CHAMELEON_DTYPE_BRIDGE: + chameleon_parse_bdd(bus, cb, p); + p += sizeof(struct chameleon_bdd); + break; + case CHAMELEON_DTYPE_END: + break; + default: + pr_err("Invalid chameleon descriptor type 0x%x\n", + dtype); + ret = -EINVAL; + goto free_bar; + } + num_cells++; + } + + if (num_cells == 0) { + ret = -EINVAL; + goto free_bar; + } + + table_size = p - base; + pr_debug("%d cell(s) found. Chameleon table size: 0x%04x bytes\n", num_cells, table_size); + kfree(cb); + kfree(header); + return table_size; + +free_bar: + kfree(cb); +free_header: + kfree(header); + + return ret; +} +EXPORT_SYMBOL_NS_GPL(chameleon_parse_cells, "MCB"); -- cgit v1.3.1