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. Signed-off-by: Akhil P Oommen <akhi...@oss.qualcomm.com> --- drivers/gpu/drm/msm/adreno/a6xx_gmu.c | 30 +++++++++++++++++++----------- drivers/gpu/drm/msm/adreno/a6xx_gmu.h | 6 ++++++ 2 files changed, 25 insertions(+), 11 deletions(-) diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gmu.c b/drivers/gpu/drm/msm/adreno/a6xx_gmu.c index 3bebb6dd7059782ceca29f2efd2acee24d3fc930..4d6c70735e0892ed87d6a68d64f24bda844e5e16 100644 --- a/drivers/gpu/drm/msm/adreno/a6xx_gmu.c +++ b/drivers/gpu/drm/msm/adreno/a6xx_gmu.c @@ -279,6 +279,8 @@ 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; } @@ -528,6 +530,9 @@ 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, @@ -555,6 +560,11 @@ 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; + + /* TODO: should we skip if IFPC is not enabled */ + gmu_write(gmu, REG_A6XX_GMU_RSCC_CONTROL_REQ, 1); ret = gmu_poll_timeout_rscc(gmu, REG_A6XX_GPU_RSCC_RSC_STATUS0_DRV0, @@ -563,6 +573,8 @@ 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) @@ -691,8 +703,6 @@ static void a6xx_gmu_rpmh_init(struct a6xx_gmu *gmu) /* ensure no writes happen before the uCode is fully written */ wmb(); - a6xx_rpmh_stop(gmu); - err: if (!IS_ERR_OR_NULL(pdcptr)) iounmap(pdcptr); @@ -852,19 +862,15 @@ 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; @@ -1046,6 +1052,8 @@ 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) diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gmu.h b/drivers/gpu/drm/msm/adreno/a6xx_gmu.h index b2d4489b40249b1916ab4a42c89e3f4bdc5c4af9..034f1b4e5a3fb9cd601bfbe6d06d64e5ace3b6e7 100644 --- a/drivers/gpu/drm/msm/adreno/a6xx_gmu.h +++ b/drivers/gpu/drm/msm/adreno/a6xx_gmu.h @@ -117,6 +117,12 @@ struct a6xx_gmu { struct qmp *qmp; struct a6xx_hfi_msg_bw_table *bw_table; + +/* 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) -- 2.50.1