[PATCH v2 2/9] drm/panthor: Use 64-bit and poll register accessors

Karunika Choo
2025-03-20T11:18:13Z

This patch updates Panthor to use the new 64-bit accessors and poll
functions.

Signed-off-by: Karunika Choo <karunika.choo@arm.com>
---
drivers/gpu/drm/panthor/panthor_fw.c | 9 +-
drivers/gpu/drm/panthor/panthor_gpu.c | 142 +++++++-------------------
drivers/gpu/drm/panthor/panthor_mmu.c | 34 ++----
3 files changed, 53 insertions(+), 132 deletions(-)

diff --git a/drivers/gpu/drm/panthor/panthor_fw.c b/drivers/gpu/drm/panthor/panthor_fw.c
index 0f52766a3120..ecfbe0456f89 100644
--- a/drivers/gpu/drm/panthor/panthor_fw.c
+++ b/drivers/gpu/drm/panthor/panthor_fw.c
@@ -1059,8 +1059,8 @@ static void panthor_fw_stop(struct panthor_device *ptdev)
u32 status;

gpu_write(ptdev, MCU_CONTROL, MCU_CONTROL_DISABLE);
- if (readl_poll_timeout(ptdev->iomem + MCU_STATUS, status,
- status == MCU_STATUS_DISABLED, 10, 100000))
+ if (gpu_read_poll_timeout(ptdev, MCU_STATUS, status,
+ status == MCU_STATUS_DISABLED, 10, 100000))
drm_err(&ptdev->base, "Failed to stop MCU");
}

@@ -1085,8 +1085,9 @@ void panthor_fw_pre_reset(struct panthor_device *ptdev, bool on_hang)

panthor_fw_update_reqs(glb_iface, req, GLB_HALT, GLB_HALT);
gpu_write(ptdev, CSF_DOORBELL(CSF_GLB_DOORBELL_ID), 1);
- if (!readl_poll_timeout(ptdev->iomem + MCU_STATUS, status,
- status == MCU_STATUS_HALT, 10, 100000)) {
+ if (!gpu_read_poll_timeout(ptdev, MCU_STATUS, status,
+ status == MCU_STATUS_HALT, 10,
+ 100000)) {
ptdev->reset.fast = true;
} else {
drm_warn(&ptdev->base, "Failed to cleanly suspend MCU");
diff --git a/drivers/gpu/drm/panthor/panthor_gpu.c b/drivers/gpu/drm/panthor/panthor_gpu.c
index 671049020afa..0dee011fe2e9 100644
--- a/drivers/gpu/drm/panthor/panthor_gpu.c
+++ b/drivers/gpu/drm/panthor/panthor_gpu.c
@@ -108,14 +108,9 @@ static void panthor_gpu_init_info(struct panthor_device *ptdev)

ptdev->gpu_info.as_present = gpu_read(ptdev, GPU_AS_PRESENT);

- ptdev->gpu_info.shader_present = gpu_read(ptdev, GPU_SHADER_PRESENT_LO);
- ptdev->gpu_info.shader_present |= (u64)gpu_read(ptdev, GPU_SHADER_PRESENT_HI) << 32;
-
- ptdev->gpu_info.tiler_present = gpu_read(ptdev, GPU_TILER_PRESENT_LO);
- ptdev->gpu_info.tiler_present |= (u64)gpu_read(ptdev, GPU_TILER_PRESENT_HI) << 32;
-
- ptdev->gpu_info.l2_present = gpu_read(ptdev, GPU_L2_PRESENT_LO);
- ptdev->gpu_info.l2_present |= (u64)gpu_read(ptdev, GPU_L2_PRESENT_HI) << 32;
+ ptdev->gpu_info.shader_present = gpu_read64(ptdev, GPU_SHADER_PRESENT_LO);
+ ptdev->gpu_info.tiler_present = gpu_read64(ptdev, GPU_TILER_PRESENT_LO);
+ ptdev->gpu_info.l2_present = gpu_read64(ptdev, GPU_L2_PRESENT_LO);

arch_major = GPU_ARCH_MAJOR(ptdev->gpu_info.gpu_id);
product_major = GPU_PROD_MAJOR(ptdev->gpu_info.gpu_id);
@@ -152,8 +147,7 @@ static void panthor_gpu_irq_handler(struct panthor_device *ptdev, u32 status)
{
if (status & GPU_IRQ_FAULT) {
u32 fault_status = gpu_read(ptdev, GPU_FAULT_STATUS);
- u64 address = ((u64)gpu_read(ptdev, GPU_FAULT_ADDR_HI) << 32) |
- gpu_read(ptdev, GPU_FAULT_ADDR_LO);
+ u64 address = gpu_read64(ptdev, GPU_FAULT_ADDR_LO);

drm_warn(&ptdev->base, "GPU Fault 0x%08x (%s) at 0x%016llx\n",
fault_status, panthor_exception_name(ptdev, fault_status & 0xFF),
@@ -244,45 +238,27 @@ int panthor_gpu_block_power_off(struct panthor_device *ptdev,
u32 pwroff_reg, u32 pwrtrans_reg,
u64 mask, u32 timeout_us)
{
- u32 val, i;
+ u32 val;
int ret;

- for (i = 0; i < 2; i++) {
- u32 mask32 = mask >> (i * 32);
-
- if (!mask32)
- continue;
-
- ret = readl_relaxed_poll_timeout(ptdev->iomem + pwrtrans_reg + (i * 4),
- val, !(mask32 & val),
- 100, timeout_us);
- if (ret) {
- drm_err(&ptdev->base, "timeout waiting on %s:%llx power transition",
- blk_name, mask);
- return ret;
- }
+ ret = gpu_read64_relaxed_poll_timeout(ptdev, pwrtrans_reg, val, !val,
+ 100, timeout_us);
+ if (ret) {
+ drm_err(&ptdev->base,
+ "timeout waiting on %s:%llx power transition", blk_name,
+ mask);
+ return ret;
}

- if (mask & GENMASK(31, 0))
- gpu_write(ptdev, pwroff_reg, mask);
-
- if (mask >> 32)
- gpu_write(ptdev, pwroff_reg + 4, mask >> 32);
-
- for (i = 0; i < 2; i++) {
- u32 mask32 = mask >> (i * 32);
+ gpu_write64(ptdev, pwroff_reg, mask);

- if (!mask32)
- continue;
-
- ret = readl_relaxed_poll_timeout(ptdev->iomem + pwrtrans_reg + (i * 4),
- val, !(mask32 & val),
- 100, timeout_us);
- if (ret) {
- drm_err(&ptdev->base, "timeout waiting on %s:%llx power transition",
- blk_name, mask);
- return ret;
- }
+ ret = gpu_read64_relaxed_poll_timeout(ptdev, pwrtrans_reg, val, !val,
+ 100, timeout_us);
+ if (ret) {
+ drm_err(&ptdev->base,
+ "timeout waiting on %s:%llx power transition", blk_name,
+ mask);
+ return ret;
}

return 0;
@@ -305,45 +281,26 @@ int panthor_gpu_block_power_on(struct panthor_device *ptdev,
u32 pwron_reg, u32 pwrtrans_reg,
u32 rdy_reg, u64 mask, u32 timeout_us)
{
- u32 val, i;
+ u32 val;
int ret;

- for (i = 0; i < 2; i++) {
- u32 mask32 = mask >> (i * 32);
-
- if (!mask32)
- continue;
-
- ret = readl_relaxed_poll_timeout(ptdev->iomem + pwrtrans_reg + (i * 4),
- val, !(mask32 & val),
- 100, timeout_us);
- if (ret) {
- drm_err(&ptdev->base, "timeout waiting on %s:%llx power transition",
- blk_name, mask);
- return ret;
- }
+ ret = gpu_read64_relaxed_poll_timeout(ptdev, pwrtrans_reg, val, !val,
+ 100, timeout_us);
+ if (ret) {
+ drm_err(&ptdev->base,
+ "timeout waiting on %s:%llx power transition", blk_name,
+ mask);
+ return ret;
}

- if (mask & GENMASK(31, 0))
- gpu_write(ptdev, pwron_reg, mask);
-
- if (mask >> 32)
- gpu_write(ptdev, pwron_reg + 4, mask >> 32);
-
- for (i = 0; i < 2; i++) {
- u32 mask32 = mask >> (i * 32);
+ gpu_write64(ptdev, pwron_reg, mask);

- if (!mask32)
- continue;
-
- ret = readl_relaxed_poll_timeout(ptdev->iomem + rdy_reg + (i * 4),
- val, (mask32 & val) == mask32,
- 100, timeout_us);
- if (ret) {
- drm_err(&ptdev->base, "timeout waiting on %s:%llx readiness",
- blk_name, mask);
- return ret;
- }
+ ret = gpu_read64_relaxed_poll_timeout(ptdev, pwrtrans_reg, val, !val,
+ 100, timeout_us);
+ if (ret) {
+ drm_err(&ptdev->base, "timeout waiting on %s:%llx readiness",
+ blk_name, mask);
+ return ret;
}

return 0;
@@ -492,26 +449,6 @@ void panthor_gpu_resume(struct panthor_device *ptdev)
panthor_gpu_l2_power_on(ptdev);
}

-/**
- * panthor_gpu_read_64bit_counter() - Read a 64-bit counter at a given offset.
- * @ptdev: Device.
- * @reg: The offset of the register to read.
- *
- * Return: The counter value.
- */
-static u64
-panthor_gpu_read_64bit_counter(struct panthor_device *ptdev, u32 reg)
-{
- u32 hi, lo;
-
- do {
- hi = gpu_read(ptdev, reg + 0x4);
- lo = gpu_read(ptdev, reg);
- } while (hi != gpu_read(ptdev, reg + 0x4));
-
- return ((u64)hi << 32) | lo;
-}
-
/**
* panthor_gpu_read_timestamp() - Read the timestamp register.
* @ptdev: Device.
@@ -520,7 +457,7 @@ panthor_gpu_read_64bit_counter(struct panthor_device *ptdev, u32 reg)
*/
u64 panthor_gpu_read_timestamp(struct panthor_device *ptdev)
{
- return panthor_gpu_read_64bit_counter(ptdev, GPU_TIMESTAMP_LO);
+ return gpu_read64_sync(ptdev, GPU_TIMESTAMP_LO);
}

/**
@@ -531,10 +468,5 @@ u64 panthor_gpu_read_timestamp(struct panthor_device *ptdev)
*/
u64 panthor_gpu_read_timestamp_offset(struct panthor_device *ptdev)
{
- u32 hi, lo;
-
- hi = gpu_read(ptdev, GPU_TIMESTAMP_OFFSET_HI);
- lo = gpu_read(ptdev, GPU_TIMESTAMP_OFFSET_LO);
-
- return ((u64)hi << 32) | lo;
+ return gpu_read64(ptdev, GPU_TIMESTAMP_OFFSET_LO);
}
diff --git a/drivers/gpu/drm/panthor/panthor_mmu.c b/drivers/gpu/drm/panthor/panthor_mmu.c
index 12a02e28f50f..a0a79f19bdea 100644
--- a/drivers/gpu/drm/panthor/panthor_mmu.c
+++ b/drivers/gpu/drm/panthor/panthor_mmu.c
@@ -510,9 +510,9 @@ static int wait_ready(struct panthor_device *ptdev, u32 as_nr)
/* Wait for the MMU status to indicate there is no active command, in
* case one is pending.
*/
- ret = readl_relaxed_poll_timeout_atomic(ptdev->iomem + AS_STATUS(as_nr),
- val, !(val & AS_STATUS_AS_ACTIVE),
- 10, 100000);
+ ret = gpu_read_relaxed_poll_timeout_atomic(ptdev, AS_STATUS(as_nr), val,
+ !(val & AS_STATUS_AS_ACTIVE),
+ 10, 100000);

if (ret) {
panthor_device_schedule_reset(ptdev);
@@ -564,8 +564,7 @@ static void lock_region(struct panthor_device *ptdev, u32 as_nr,
region = region_width | region_start;

/* Lock the region that needs to be updated */
- gpu_write(ptdev, AS_LOCKADDR_LO(as_nr), lower_32_bits(region));
- gpu_write(ptdev, AS_LOCKADDR_HI(as_nr), upper_32_bits(region));
+ gpu_write64(ptdev, AS_LOCKADDR_LO(as_nr), region);
write_cmd(ptdev, as_nr, AS_COMMAND_LOCK);
}

@@ -615,14 +614,9 @@ static int panthor_mmu_as_enable(struct panthor_device *ptdev, u32 as_nr,
if (ret)
return ret;

- gpu_write(ptdev, AS_TRANSTAB_LO(as_nr), lower_32_bits(transtab));
- gpu_write(ptdev, AS_TRANSTAB_HI(as_nr), upper_32_bits(transtab));
-
- gpu_write(ptdev, AS_MEMATTR_LO(as_nr), lower_32_bits(memattr));
- gpu_write(ptdev, AS_MEMATTR_HI(as_nr), upper_32_bits(memattr));
-
- gpu_write(ptdev, AS_TRANSCFG_LO(as_nr), lower_32_bits(transcfg));
- gpu_write(ptdev, AS_TRANSCFG_HI(as_nr), upper_32_bits(transcfg));
+ gpu_write64(ptdev, AS_TRANSTAB_LO(as_nr), transtab);
+ gpu_write64(ptdev, AS_MEMATTR_LO(as_nr), memattr);
+ gpu_write64(ptdev, AS_TRANSCFG_LO(as_nr), transcfg);

return write_cmd(ptdev, as_nr, AS_COMMAND_UPDATE);
}
@@ -635,14 +629,9 @@ static int panthor_mmu_as_disable(struct panthor_device *ptdev, u32 as_nr)
if (ret)
return ret;

- gpu_write(ptdev, AS_TRANSTAB_LO(as_nr), 0);
- gpu_write(ptdev, AS_TRANSTAB_HI(as_nr), 0);
-
- gpu_write(ptdev, AS_MEMATTR_LO(as_nr), 0);
- gpu_write(ptdev, AS_MEMATTR_HI(as_nr), 0);
-
- gpu_write(ptdev, AS_TRANSCFG_LO(as_nr), AS_TRANSCFG_ADRMODE_UNMAPPED);
- gpu_write(ptdev, AS_TRANSCFG_HI(as_nr), 0);
+ gpu_write64(ptdev, AS_TRANSTAB_LO(as_nr), 0);
+ gpu_write64(ptdev, AS_MEMATTR_LO(as_nr), 0);
+ gpu_write64(ptdev, AS_TRANSCFG_LO(as_nr), AS_TRANSCFG_ADRMODE_UNMAPPED);

return write_cmd(ptdev, as_nr, AS_COMMAND_UPDATE);
}
@@ -1680,8 +1669,7 @@ static void panthor_mmu_irq_handler(struct panthor_device *ptdev, u32 status)
u32 source_id;

fault_status = gpu_read(ptdev, AS_FAULTSTATUS(as));
- addr = gpu_read(ptdev, AS_FAULTADDRESS_LO(as));
- addr |= (u64)gpu_read(ptdev, AS_FAULTADDRESS_HI(as)) << 32;
+ addr = gpu_read64(ptdev, AS_FAULTADDRESS_LO(as));

/* decode the fault status */
exception_type = fault_status & 0xFF;
--
2.47.1