drm/msm/a6xx: Fix PDC sleep sequence

[ Upstream commit f248d5d515 ]

Since the PDC resides out of the GPU subsystem and cannot be reset in
case it enters bad state, utmost care must be taken to trigger the PDC
wake/sleep routines in the correct order.

The PDC wake sequence can be exercised only after a PDC sleep sequence.
Additionally, GMU firmware should initialize a few registers before the
KMD can trigger a PDC sleep sequence. So PDC sleep can't be done if the
GMU firmware has not initialized. Track these dependencies using a new
status variable and trigger PDC sleep/wake sequences appropriately.

Cc: stable@vger.kernel.org
Fixes: 4b565ca5a2 ("drm/msm: Add A6XX device support")
Signed-off-by: Akhil P Oommen <akhilpo@oss.qualcomm.com>
Patchwork: https://patchwork.freedesktop.org/patch/673362/
Signed-off-by: Rob Clark <robin.clark@oss.qualcomm.com>
[ Adjust context ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Akhil P Oommen
2025-10-17 22:28:32 -04:00
committed by Greg Kroah-Hartman
parent 2e24713ba2
commit 3e7b89ed9f
2 changed files with 23 additions and 11 deletions

View File

@@ -236,6 +236,8 @@ static int a6xx_gmu_start(struct a6xx_gmu *gmu)
if (ret)
DRM_DEV_ERROR(gmu->dev, "GMU firmware initialization timed out\n");
set_bit(GMU_STATUS_FW_START, &gmu->status);
return ret;
}
@@ -482,6 +484,9 @@ static int a6xx_rpmh_start(struct a6xx_gmu *gmu)
int ret;
u32 val;
if (!test_and_clear_bit(GMU_STATUS_PDC_SLEEP, &gmu->status))
return 0;
gmu_write(gmu, REG_A6XX_GMU_RSCC_CONTROL_REQ, BIT(1));
ret = gmu_poll_timeout(gmu, REG_A6XX_GMU_RSCC_CONTROL_ACK, val,
@@ -509,6 +514,9 @@ static void a6xx_rpmh_stop(struct a6xx_gmu *gmu)
int ret;
u32 val;
if (test_and_clear_bit(GMU_STATUS_FW_START, &gmu->status))
return;
gmu_write(gmu, REG_A6XX_GMU_RSCC_CONTROL_REQ, 1);
ret = gmu_poll_timeout_rscc(gmu, REG_A6XX_GPU_RSCC_RSC_STATUS0_DRV0,
@@ -517,6 +525,8 @@ static void a6xx_rpmh_stop(struct a6xx_gmu *gmu)
DRM_DEV_ERROR(gmu->dev, "Unable to power off the GPU RSC\n");
gmu_write(gmu, REG_A6XX_GMU_RSCC_CONTROL_REQ, 0);
set_bit(GMU_STATUS_PDC_SLEEP, &gmu->status);
}
static inline void pdc_write(void __iomem *ptr, u32 offset, u32 value)
@@ -645,8 +655,6 @@ setup_pdc:
/* ensure no writes happen before the uCode is fully written */
wmb();
a6xx_rpmh_stop(gmu);
err:
if (!IS_ERR_OR_NULL(pdcptr))
iounmap(pdcptr);
@@ -799,19 +807,15 @@ static int a6xx_gmu_fw_start(struct a6xx_gmu *gmu, unsigned int state)
else
gmu_write(gmu, REG_A6XX_GMU_GENERAL_7, 1);
if (state == GMU_WARM_BOOT) {
ret = a6xx_rpmh_start(gmu);
if (ret)
return ret;
} else {
ret = a6xx_rpmh_start(gmu);
if (ret)
return ret;
if (state == GMU_COLD_BOOT) {
if (WARN(!adreno_gpu->fw[ADRENO_FW_GMU],
"GMU firmware is not loaded\n"))
return -ENOENT;
ret = a6xx_rpmh_start(gmu);
if (ret)
return ret;
ret = a6xx_gmu_fw_load(gmu);
if (ret)
return ret;
@@ -980,6 +984,8 @@ static void a6xx_gmu_force_off(struct a6xx_gmu *gmu)
/* Reset GPU core blocks */
a6xx_gpu_sw_reset(gpu, true);
a6xx_rpmh_stop(gmu);
}
static void a6xx_gmu_set_initial_freq(struct msm_gpu *gpu, struct a6xx_gmu *gmu)

View File

@@ -99,6 +99,12 @@ struct a6xx_gmu {
struct completion pd_gate;
struct qmp *qmp;
/* To check if we can trigger sleep seq at PDC. Cleared in a6xx_rpmh_stop() */
#define GMU_STATUS_FW_START 0
/* To track if PDC sleep seq was done */
#define GMU_STATUS_PDC_SLEEP 1
unsigned long status;
};
static inline u32 gmu_read(struct a6xx_gmu *gmu, u32 offset)