Add resource-group probing for the arbitration device, including MMIO resources, IRQ handling, per-AW AM message helpers, handshake negotiation, and retry work for deferred outgoing messages.
Hook resource groups into arbitration init, teardown, and runtime PM. Signed-off-by: Karunika Choo <[email protected]> --- v1: - Updated DT structure and accompanying parsing to handle child nodes instead of named platform resources. - Hold runtime PM reference during message retries. - Fix suspend resume ordering. drivers/gpu/drm/panthor/arbitration/Makefile | 3 +- .../panthor/arbitration/panthor_arbitration.h | 5 + .../arbitration/panthor_arbitration_drv.c | 19 +- .../arbitration/panthor_resource_group.c | 323 ++++++++++++++++++ .../arbitration/panthor_resource_group.h | 22 ++ 5 files changed, 370 insertions(+), 2 deletions(-) create mode 100644 drivers/gpu/drm/panthor/arbitration/panthor_resource_group.c create mode 100644 drivers/gpu/drm/panthor/arbitration/panthor_resource_group.h diff --git a/drivers/gpu/drm/panthor/arbitration/Makefile b/drivers/gpu/drm/panthor/arbitration/Makefile index b0b6b2e3edf8d..2d2684321d978 100644 --- a/drivers/gpu/drm/panthor/arbitration/Makefile +++ b/drivers/gpu/drm/panthor/arbitration/Makefile @@ -4,7 +4,8 @@ obj-$(CONFIG_DRM_PANTHOR_ARBITRATION) += panthor_arbitration.o panthor_arbitration-y := \ panthor_arbitration_drv.o \ - panthor_partition_control.o + panthor_partition_control.o \ + panthor_resource_group.o INCLUDES = \ -I$(src)/.. diff --git a/drivers/gpu/drm/panthor/arbitration/panthor_arbitration.h b/drivers/gpu/drm/panthor/arbitration/panthor_arbitration.h index 26950e47852dd..dfeab1b078d06 100644 --- a/drivers/gpu/drm/panthor/arbitration/panthor_arbitration.h +++ b/drivers/gpu/drm/panthor/arbitration/panthor_arbitration.h @@ -9,8 +9,10 @@ struct device; struct panthor_partition_control; +struct panthor_resource_group; #define AM_ARB_MAX_PC_COUNT 1 +#define AM_ARB_MAX_RG_COUNT 1 #define AM_ARB_MAX_AW_COUNT 16 /** struct panthor_arbitration_resource - Arbitration resource */ @@ -31,6 +33,9 @@ struct panthor_arbitration { /** @pc: Pointer array to partition control data */ struct panthor_partition_control *pc[AM_ARB_MAX_PC_COUNT]; + + /** @rg: Pointer array to resource group data */ + struct panthor_resource_group *rg[AM_ARB_MAX_RG_COUNT]; }; int panthor_arbitration_parse_resource(struct device *dev, diff --git a/drivers/gpu/drm/panthor/arbitration/panthor_arbitration_drv.c b/drivers/gpu/drm/panthor/arbitration/panthor_arbitration_drv.c index 09342245a47d1..a1068a2c78f1a 100644 --- a/drivers/gpu/drm/panthor/arbitration/panthor_arbitration_drv.c +++ b/drivers/gpu/drm/panthor/arbitration/panthor_arbitration_drv.c @@ -12,6 +12,7 @@ #include "panthor_arbitration.h" #include "panthor_partition_control.h" +#include "panthor_resource_group.h" #define PANTHOR_PM_AUTOSUSPEND_DELAY_MS 100 @@ -55,6 +56,10 @@ static int panthor_arbitration_runtime_suspend(struct device *dev) struct panthor_arbitration *adev = dev_get_drvdata(dev); int ret = 0; + ret = panthor_resource_group_suspend(adev); + if (ret) + return ret; + ret = panthor_partition_control_suspend(adev); if (ret) return ret; @@ -71,6 +76,10 @@ static int panthor_arbitration_runtime_resume(struct device *dev) if (ret) return ret; + ret = panthor_resource_group_resume(adev); + if (ret) + return ret; + return 0; } @@ -103,6 +112,10 @@ static int panthor_arbitration_probe(struct platform_device *pdev) if (ret) goto err_term_pc; + ret = panthor_resource_group_init(adev); + if (ret) + goto err_term_rg; + ret = of_platform_populate(dev->of_node, NULL, NULL, dev); if (ret) goto err_depopulate; @@ -116,7 +129,9 @@ static int panthor_arbitration_probe(struct platform_device *pdev) err_depopulate: of_platform_depopulate(dev); - +err_term_rg: + panthor_resource_group_cancel_work(adev); + panthor_resource_group_term(adev); err_term_pc: panthor_partition_control_term(adev); pm_runtime_put_noidle(dev); @@ -136,8 +151,10 @@ static void panthor_arbitration_remove(struct platform_device *pdev) dev_warn(adev->dev, "failed to resume during remove: %d", ret); of_platform_depopulate(adev->dev); + panthor_resource_group_cancel_work(adev); if (ret >= 0) { + panthor_resource_group_term(adev); panthor_partition_control_term(adev); pm_runtime_put_noidle(adev->dev); } diff --git a/drivers/gpu/drm/panthor/arbitration/panthor_resource_group.c b/drivers/gpu/drm/panthor/arbitration/panthor_resource_group.c new file mode 100644 index 0000000000000..9bdd0876dd457 --- /dev/null +++ b/drivers/gpu/drm/panthor/arbitration/panthor_resource_group.c @@ -0,0 +1,323 @@ +// SPDX-License-Identifier: GPL-2.0 or MIT +/* Copyright 2026 ARM Limited. All rights reserved. */ + +#include <linux/interrupt.h> +#include <linux/iopoll.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/property.h> +#include <linux/workqueue.h> + +#include "panthor_am_msg.h" +#include "panthor_arbitration.h" +#include "panthor_device_io.h" +#include "panthor_resource_group.h" + +#define AM_RG_IRQ_RAWSTAT 0x80 +#define AM_RG_IRQ_CLEAR 0x84 +#define AM_RG_IRQ_MASK 0x88 +#define AM_RG_IRQ_STATUS 0x8C +#define AM_RG_MESSAGE_MASK GENMASK(15, 0) + +#define AM_RG_AW_MESSAGE(n) (0x100 + (n) * 0x20) + +struct rg_aw_data { + /** @msg: Messaging data */ + struct panthor_am_msg msg; +}; + +struct panthor_resource_group { + /** @dev: Device pointer */ + struct device *dev; + + /** @name: Resource name */ + char *name; + + /** @iomem: CPU mapping of the partition control IOMEM region */ + void __iomem *iomem; + + /** @irq: IRQ number */ + int irq; + + /** @aw_data: Data for each access window */ + struct rg_aw_data aw_data[AM_ARB_MAX_AW_COUNT]; + + /** @wq: Resource group workqueue */ + struct workqueue_struct *wq; + + /** @msg_retry_work: Work to retry sending pending messages */ + struct work_struct msg_retry_work; +}; + +static void rg_retry_messages(struct work_struct *work) +{ + struct panthor_resource_group *rg = container_of( + work, struct panthor_resource_group, msg_retry_work); + bool retry = false; + int ret; + + ret = pm_runtime_resume_and_get(rg->dev); + if (ret) { + dev_warn(rg->dev, "Failed to resume to retry messages"); + return; + } + + for (u8 aw_id = 0; aw_id < AM_ARB_MAX_AW_COUNT; aw_id++) { + struct panthor_am_msg *msg = &rg->aw_data[aw_id].msg; + int ret; + + ret = panthor_am_msg_retry(msg); + if (ret == -EBUSY || ret == -EAGAIN) + retry = true; + + if (ret == -EINVAL) + dev_warn(rg->dev, "AW%u send FIFO unexpectedly empty", aw_id); + } + + if (retry) + queue_work(rg->wq, &rg->msg_retry_work); + + pm_runtime_put_autosuspend(rg->dev); +} + +static void rg_send_msg(struct panthor_resource_group *rg, u8 aw_id, + u64 message) +{ + int ret; + + ret = panthor_am_msg_send(&rg->aw_data[aw_id].msg, message); + if (ret == -ENOSPC) + dev_err(rg->dev, "AW%u send FIFO is full", aw_id); + + if (ret == -EBUSY) { + dev_dbg(rg->dev, "AW%u has pending messages, scheduling retry work", aw_id); + queue_work(rg->wq, &rg->msg_retry_work); + } +} + +static void rg_send_init_msg(struct panthor_resource_group *rg, u8 aw_id, + u8 ack, u8 version) +{ + u64 message = ARB_VM_INIT_MAKE(ack, version); + + rg_send_msg(rg, aw_id, message); +} + +static void rg_respond_to_handshake(struct panthor_resource_group *rg, + u8 aw_id, u64 message) +{ + struct rg_aw_data *aw_data = &rg->aw_data[aw_id]; + bool acked = AM_MSG_ACK_GET(message); + u8 version = AM_MSG_VERSION_GET(message); + int ret; + + ret = panthor_am_msg_version_validate(&aw_data->msg, version); + if (ret == -EOPNOTSUPP) + dev_warn(rg->dev, + "AW%u protocol version less than minimum supported (%u < %u)", + aw_id, version, AM_MSG_MIN_SUPPORTED_VERSION); + + /* AW initiated the handshake, reply with supported version */ + if (!acked) + rg_send_init_msg(rg, aw_id, 1, aw_data->msg.version); +} + +static void rg_handshake_init(struct panthor_resource_group *rg) +{ + for (u8 aw_id = 0; aw_id < AM_ARB_MAX_AW_COUNT; aw_id++) + rg_send_init_msg(rg, aw_id, 0, AM_MSG_CURRENT_VERSION); +} + +static void rg_handle_message(struct panthor_resource_group *rg, u8 aw_id, + u64 message) +{ + u8 msg_id = AM_MSG_ID_GET(message); + if (!msg_id) + return; + + switch (msg_id) { + case VM_ARB_INIT: + rg_respond_to_handshake(rg, aw_id, message); + break; + case VM_ARB_GPU_REQUEST: + /* TODO: on_request */ + break; + case VM_ARB_GPU_STOPPED: + /* TODO: on_idle */ + break; + default: + dev_warn(rg->dev, "Invalid message (0x%llx)", message); + break; + } +} + +static irqreturn_t rg_irq_raw_handler(int irq, void *data) +{ + struct panthor_resource_group *rg = data; + unsigned long message_mask; + u32 status; + u8 aw_id; + + status = gpu_read(rg->iomem, AM_RG_IRQ_STATUS); + if (!status) + return IRQ_NONE; + + message_mask = status; + for_each_set_bit(aw_id, &message_mask, AM_ARB_MAX_AW_COUNT) { + u64 message = panthor_am_msg_read(&rg->aw_data[aw_id].msg); + + rg_handle_message(rg, aw_id, message); + } + + gpu_write(rg->iomem, AM_RG_IRQ_CLEAR, status); + + return IRQ_HANDLED; +} + +static void rg_irq_suspend(struct panthor_resource_group *rg) +{ + gpu_write(rg->iomem, AM_RG_IRQ_MASK, 0); +} + +static void rg_irq_resume(struct panthor_resource_group *rg) +{ + gpu_write(rg->iomem, AM_RG_IRQ_MASK, AM_RG_MESSAGE_MASK); +} + +int panthor_resource_group_suspend(struct panthor_arbitration *adev) +{ + for (int i = 0; i < AM_ARB_MAX_RG_COUNT; i++) { + struct panthor_resource_group *rg = adev->rg[i]; + + if (!rg) + continue; + + rg_irq_suspend(rg); + } + + return 0; +} + +int panthor_resource_group_resume(struct panthor_arbitration *adev) +{ + for (int i = 0; i < AM_ARB_MAX_RG_COUNT; i++) { + struct panthor_resource_group *rg = adev->rg[i]; + + if (!rg) + continue; + + rg_irq_resume(rg); + } + + return 0; +} + +void panthor_resource_group_cancel_work(struct panthor_arbitration *adev) +{ + for (int i = 0; i < AM_ARB_MAX_RG_COUNT; i++) { + struct panthor_resource_group *rg = adev->rg[i]; + + if (!rg) + continue; + + disable_work_sync(&rg->msg_retry_work); + } +} + +void panthor_resource_group_term(struct panthor_arbitration *adev) +{ + for (int i = 0; i < AM_ARB_MAX_RG_COUNT; i++) { + struct panthor_resource_group *rg = adev->rg[i]; + + if (!rg) + continue; + + rg_irq_suspend(rg); + } +} + +static int resource_group_init(struct panthor_arbitration *adev, + const struct fwnode_handle *child) +{ + struct panthor_arbitration_resource res; + struct panthor_resource_group *rg; + struct device *dev = adev->dev; + struct irq_data *irqdata; + void __iomem *iomem; + u32 irq_flags = 0; + char *name; + int irq; + int ret; + + ret = panthor_arbitration_parse_resource(dev, child, &res); + if (ret) + return ret; + + if (res.id >= AM_ARB_MAX_RG_COUNT) + return -ENODEV; + + if (adev->rg[res.id]) + return dev_warn_probe(dev, -ENODEV, "resource-group@%llx: id (%u) already present", + res.res.start, res.id); + + rg = devm_kzalloc(dev, sizeof(*rg), GFP_KERNEL); + if (!rg) + return -ENOMEM; + + name = devm_kasprintf(dev, GFP_KERNEL, "rg%d", res.id); + + iomem = devm_ioremap_resource(dev, &res.res); + if (IS_ERR(iomem)) + return dev_err_probe(dev, PTR_ERR(iomem), "%s: Failed to ioremap", name); + + rg->name = name; + rg->dev = dev; + rg->iomem = iomem; + + rg->wq = devm_alloc_ordered_workqueue(dev, "panthor-%s-wq", 0, name); + if (!rg->wq) + return -ENOMEM; + + INIT_WORK(&rg->msg_retry_work, rg_retry_messages); + + for (int i = 0; i < AM_ARB_MAX_AW_COUNT; i++) + panthor_am_msg_init(&rg->aw_data[i].msg, + rg->iomem + AM_RG_AW_MESSAGE(i)); + + irq = fwnode_irq_get(child, 0); + if (irq < 0) + return dev_err_probe(dev, irq, "%s: Failed to get IRQ", name); + + irqdata = irq_get_irq_data(irq); + if (irqdata) + irq_flags = irqd_get_trigger_type(irqdata); + + ret = devm_request_irq( + dev, irq, rg_irq_raw_handler, irq_flags | IRQF_SHARED, + devm_kasprintf(dev, GFP_KERNEL, "panthor-%s-irq", name), rg); + if (ret) + return ret; + + adev->rg[res.id] = rg; + + rg_irq_resume(rg); + + rg_handshake_init(rg); + + return 0; +} + +int panthor_resource_group_init(struct panthor_arbitration *adev) +{ + device_for_each_named_child_node_scoped(adev->dev, child, "resource-group") { + int ret = resource_group_init(adev, child); + + if (ret == -ENODEV) + continue; + + if (ret) + return ret; + } + + return 0; +} diff --git a/drivers/gpu/drm/panthor/arbitration/panthor_resource_group.h b/drivers/gpu/drm/panthor/arbitration/panthor_resource_group.h new file mode 100644 index 0000000000000..ad85cd171c4a3 --- /dev/null +++ b/drivers/gpu/drm/panthor/arbitration/panthor_resource_group.h @@ -0,0 +1,22 @@ +/* SPDX-License-Identifier: GPL-2.0 or MIT */ +/* Copyright 2026 ARM Limited. All rights reserved. */ + +#ifndef __PANTHOR_RESOURCE_GROUP_H__ +#define __PANTHOR_RESOURCE_GROUP_H__ + +#include <linux/types.h> + +struct device; +struct panthor_arbitration; + +int panthor_resource_group_init(struct panthor_arbitration *adev); + +void panthor_resource_group_term(struct panthor_arbitration *adev); + +int panthor_resource_group_suspend(struct panthor_arbitration *adev); + +int panthor_resource_group_resume(struct panthor_arbitration *adev); + +void panthor_resource_group_cancel_work(struct panthor_arbitration *adev); + +#endif -- 2.43.0
