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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
commit4352b8aee98005853aa63f57d6377282de17a33f (patch)
tree27614d7a9ef05c32d089004e104364ce42324837 /drivers/cdx/cdx_msi.c
downloadlinux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz
linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
Pull I3C updates from Alexandre Belloni: "A new driver this cycle, for the AMD AXI I3C controller. There are also new features such as IBI wakeup support, SETAASA device discovery and ACPI support for the the DAA methods, meaning we can now communicate with the SPD devices on DDR5 modules. New driver: - AMD AXI I3C master controller Subsystem: - I3C Common Command Code (CCC) handling improvements, especially around GET CCCs - SETAASA device discovery support - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as well as I2C devices on I3C bus - IBI-based wakeup support Drivers: - dw: SETAASA support - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C controller support, PIO queue management support for HCI v1.2 - renesas: improve suspend to RAM support, add runtime PM support" * tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits) i3c: dw: reduce do_daa time if there's no client i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2 i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode i3c: dw: rename "pclk" to "apb" to match dt-binding i3c: dw: make struct dw_i3c_cmd smaller i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding i3c: renesas: Don't register devices when ENTDAA times out i3c: master: dw-i3c-master: fix OD timing for first broadcast i3c: mipi-i3c-hci: Advertise IBI wakeup capability i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev() i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI i3c: master: Reject IBI requests from non-IBI-capable devices i3c: master: Add helper to query bus wakeup requirements i3c: master: Report wakeup events for IBIs i3c: master: Support IBI-based wakeup capability i3c: master: Fix potential UAF in i3c_device_match() i3c: master: Fix potential UAF in i3c_device_uevent() i3c: Make dev->desc locking assumptions explicit i3c: master: Fix use-after-free of master->this ...
Diffstat (limited to 'drivers/cdx/cdx_msi.c')
-rw-r--r--drivers/cdx/cdx_msi.c193
1 files changed, 193 insertions, 0 deletions
diff --git a/drivers/cdx/cdx_msi.c b/drivers/cdx/cdx_msi.c
new file mode 100644
index 000000000..c8d832b0b
--- /dev/null
+++ b/drivers/cdx/cdx_msi.c
@@ -0,0 +1,193 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * AMD CDX bus driver MSI support
+ *
+ * Copyright (C) 2022-2023, Advanced Micro Devices, Inc.
+ */
+
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
+#include <linux/msi.h>
+#include <linux/cdx/cdx_bus.h>
+
+#include "cdx.h"
+
+static void cdx_msi_write_msg(struct irq_data *irq_data, struct msi_msg *msg)
+{
+ struct msi_desc *msi_desc = irq_data_get_msi_desc(irq_data);
+ struct cdx_device *cdx_dev = to_cdx_device(msi_desc->dev);
+
+ /* We would not operate on msg here rather we wait for irq_bus_sync_unlock()
+ * to be called from preemptible task context.
+ */
+ msi_desc->msg = *msg;
+ cdx_dev->msi_write_pending = true;
+}
+
+static void cdx_msi_write_irq_lock(struct irq_data *irq_data)
+{
+ struct msi_desc *msi_desc = irq_data_get_msi_desc(irq_data);
+ struct cdx_device *cdx_dev = to_cdx_device(msi_desc->dev);
+
+ mutex_lock(&cdx_dev->irqchip_lock);
+}
+
+static void cdx_msi_write_irq_unlock(struct irq_data *irq_data)
+{
+ struct msi_desc *msi_desc = irq_data_get_msi_desc(irq_data);
+ struct cdx_device *cdx_dev = to_cdx_device(msi_desc->dev);
+ struct cdx_controller *cdx = cdx_dev->cdx;
+ struct cdx_device_config dev_config;
+
+ if (!cdx_dev->msi_write_pending) {
+ mutex_unlock(&cdx_dev->irqchip_lock);
+ return;
+ }
+
+ cdx_dev->msi_write_pending = false;
+ mutex_unlock(&cdx_dev->irqchip_lock);
+
+ dev_config.msi.msi_index = msi_desc->msi_index;
+ dev_config.msi.data = msi_desc->msg.data;
+ dev_config.msi.addr = ((u64)(msi_desc->msg.address_hi) << 32) | msi_desc->msg.address_lo;
+
+ /*
+ * dev_configure() is a controller callback which can interact with
+ * Firmware or other entities, and can sleep, so invoke this function
+ * outside of the mutex held region.
+ */
+ dev_config.type = CDX_DEV_MSI_CONF;
+ if (cdx->ops->dev_configure)
+ cdx->ops->dev_configure(cdx, cdx_dev->bus_num, cdx_dev->dev_num, &dev_config);
+}
+
+int cdx_enable_msi(struct cdx_device *cdx_dev)
+{
+ struct cdx_controller *cdx = cdx_dev->cdx;
+ struct cdx_device_config dev_config;
+
+ dev_config.type = CDX_DEV_MSI_ENABLE;
+ dev_config.msi_enable = true;
+ if (cdx->ops->dev_configure) {
+ return cdx->ops->dev_configure(cdx, cdx_dev->bus_num, cdx_dev->dev_num,
+ &dev_config);
+ }
+
+ return -EOPNOTSUPP;
+}
+EXPORT_SYMBOL_GPL(cdx_enable_msi);
+
+void cdx_disable_msi(struct cdx_device *cdx_dev)
+{
+ struct cdx_controller *cdx = cdx_dev->cdx;
+ struct cdx_device_config dev_config;
+
+ dev_config.type = CDX_DEV_MSI_ENABLE;
+ dev_config.msi_enable = false;
+ if (cdx->ops->dev_configure)
+ cdx->ops->dev_configure(cdx, cdx_dev->bus_num, cdx_dev->dev_num, &dev_config);
+}
+EXPORT_SYMBOL_GPL(cdx_disable_msi);
+
+static struct irq_chip cdx_msi_irq_chip = {
+ .name = "CDX-MSI",
+ .irq_mask = irq_chip_mask_parent,
+ .irq_unmask = irq_chip_unmask_parent,
+ .irq_eoi = irq_chip_eoi_parent,
+ .irq_set_affinity = msi_domain_set_affinity,
+ .irq_write_msi_msg = cdx_msi_write_msg,
+ .irq_bus_lock = cdx_msi_write_irq_lock,
+ .irq_bus_sync_unlock = cdx_msi_write_irq_unlock
+};
+
+/* Convert an msi_desc to a unique identifier within the domain. */
+static irq_hw_number_t cdx_domain_calc_hwirq(struct cdx_device *dev,
+ struct msi_desc *desc)
+{
+ return ((irq_hw_number_t)dev->msi_dev_id << 10) | desc->msi_index;
+}
+
+static void cdx_msi_set_desc(msi_alloc_info_t *arg, struct msi_desc *desc)
+{
+ arg->desc = desc;
+ arg->hwirq = cdx_domain_calc_hwirq(to_cdx_device(desc->dev), desc);
+}
+
+static int cdx_msi_prepare(struct irq_domain *msi_domain,
+ struct device *dev,
+ int nvec, msi_alloc_info_t *info)
+{
+ struct of_phandle_args msi_spec = {};
+ struct cdx_device *cdx_dev = to_cdx_device(dev);
+ struct device *parent = cdx_dev->cdx->dev;
+ struct msi_domain_info *msi_info;
+ int ret;
+
+ /* Retrieve device ID from requestor ID using parent device */
+ ret = of_map_msi_id(parent->of_node, cdx_dev->msi_dev_id, NULL, &msi_spec);
+ if (ret) {
+ dev_err(dev, "of_map_msi_id failed for MSI: %d\n", ret);
+ return ret;
+ }
+ of_node_put(msi_spec.np);
+
+#ifdef GENERIC_MSI_DOMAIN_OPS
+ /* Set the device Id to be passed to the GIC-ITS */
+ info->scratchpad[0].ul = msi_spec.args[0];
+#endif
+
+ msi_info = msi_get_domain_info(msi_domain->parent);
+
+ return msi_info->ops->msi_prepare(msi_domain->parent, dev, nvec, info);
+}
+
+static struct msi_domain_ops cdx_msi_ops = {
+ .msi_prepare = cdx_msi_prepare,
+ .set_desc = cdx_msi_set_desc
+};
+
+static struct msi_domain_info cdx_msi_domain_info = {
+ .ops = &cdx_msi_ops,
+ .chip = &cdx_msi_irq_chip,
+ .flags = MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
+ MSI_FLAG_ALLOC_SIMPLE_MSI_DESCS | MSI_FLAG_FREE_MSI_DESCS
+};
+
+struct irq_domain *cdx_msi_domain_init(struct device *dev)
+{
+ struct device_node *np = dev->of_node;
+ struct fwnode_handle *fwnode_handle;
+ struct irq_domain *cdx_msi_domain;
+ struct device_node *parent_node;
+ struct irq_domain *parent;
+
+ fwnode_handle = of_fwnode_handle(np);
+
+ parent_node = of_parse_phandle(np, "msi-map", 1);
+ if (!parent_node) {
+ dev_err(dev, "msi-map not present on cdx controller\n");
+ return NULL;
+ }
+
+ parent = irq_find_matching_fwnode(of_fwnode_handle(parent_node), DOMAIN_BUS_NEXUS);
+ of_node_put(parent_node);
+ if (!parent || !msi_get_domain_info(parent)) {
+ dev_err(dev, "unable to locate ITS domain\n");
+ return NULL;
+ }
+
+ cdx_msi_domain = msi_create_irq_domain(fwnode_handle, &cdx_msi_domain_info, parent);
+ if (!cdx_msi_domain) {
+ dev_err(dev, "unable to create CDX-MSI domain\n");
+ return NULL;
+ }
+
+ dev_dbg(dev, "CDX-MSI domain created\n");
+
+ return cdx_msi_domain;
+}
+EXPORT_SYMBOL_NS_GPL(cdx_msi_domain_init, "CDX_BUS_CONTROLLER");