[PATCH 3/8] drm/msm/a6xx: Fix stale boot up BW vote

[Akhil P Oommen]

From: Jie Zhang <jie.zhang@xxxxxxxxxxxxxxxx>

An initial bus bandwidth is voted during boot to bring up the GMU. In GPUs
where the GMU drives bandwidth scaling, this boot-time BW vote is
redundant and can be removed.

Fixes: 7047e655a567 ("drm/msm: adreno: find bandwidth index of OPP and set it along freq index")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Jie Zhang <jie.zhang@xxxxxxxxxxxxxxxx>
Signed-off-by: Akhil P Oommen <akhilpo@xxxxxxxxxxxxxxxx>
---
 drivers/gpu/drm/msm/adreno/a6xx_gmu.c | 16 +++++++++++++---
 drivers/gpu/drm/msm/adreno/a6xx_gmu.h |  1 +
 drivers/gpu/drm/msm/adreno/a6xx_hfi.c |  2 +-
 3 files changed, 15 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gmu.c b/drivers/gpu/drm/msm/adreno/a6xx_gmu.c
index 7e80670736a6..991db3c9cd96 100644
--- a/drivers/gpu/drm/msm/adreno/a6xx_gmu.c
+++ b/drivers/gpu/drm/msm/adreno/a6xx_gmu.c
@@ -76,6 +76,13 @@ static irqreturn_t a6xx_hfi_irq(int irq, void *data)
 	return IRQ_HANDLED;
 }
 
+bool a6xx_gmu_scales_bw(struct a6xx_gmu *gmu)
+{
+	struct a6xx_gpu *a6xx_gpu = container_of(gmu, struct a6xx_gpu, gmu);
+
+	return a6xx_gpu->base.info->a6xx->bcms && gmu->nr_gpu_bws > 1;
+}
+
 bool a6xx_gmu_sptprac_is_on(struct a6xx_gmu *gmu)
 {
 	u32 val;
@@ -169,7 +176,6 @@ void a6xx_gmu_set_freq(struct msm_gpu *gpu, struct dev_pm_opp *opp,
 		       bool suspended)
 {
 	struct adreno_gpu *adreno_gpu = to_adreno_gpu(gpu);
-	const struct a6xx_info *info = adreno_gpu->info->a6xx;
 	struct a6xx_gpu *a6xx_gpu = to_a6xx_gpu(adreno_gpu);
 	struct a6xx_gmu *gmu = &a6xx_gpu->gmu;
 	u32 perf_index;
@@ -187,7 +193,7 @@ void a6xx_gmu_set_freq(struct msm_gpu *gpu, struct dev_pm_opp *opp,
 			break;
 
 	/* If enabled, find the corresponding DDR bandwidth index */
-	if (info->bcms && gmu->nr_gpu_bws > 1) {
+	if (a6xx_gmu_scales_bw(gmu)) {
 		unsigned int bw = dev_pm_opp_get_bw(opp, true, 0);
 
 		for (bw_index = 0; bw_index < gmu->nr_gpu_bws - 1; bw_index++) {
@@ -1393,6 +1399,10 @@ int a6xx_gmu_resume(struct a6xx_gpu *a6xx_gpu)
 	/* Set the GPU to the current freq */
 	a6xx_gmu_set_initial_freq(gpu, gmu);
 
+	/* Clear the boot bus quota to allow GMU-driven BW scaling */
+	if (a6xx_gmu_scales_bw(gmu))
+		dev_pm_opp_set_opp(&gpu->pdev->dev, NULL);
+
 	return 0;
 
 disable_irq:
@@ -1913,7 +1923,7 @@ static int a6xx_gmu_rpmh_votes_init(struct a6xx_gmu *gmu)
 		gmu->gmu_freqs, gmu->nr_gmu_freqs, "cx.lvl", "mx.lvl");
 
 	/* Build the interconnect votes */
-	if (info->bcms && gmu->nr_gpu_bws > 1)
+	if (a6xx_gmu_scales_bw(gmu))
 		ret |= a6xx_gmu_rpmh_bw_votes_init(adreno_gpu, info, gmu);
 
 	return ret;
diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gmu.h b/drivers/gpu/drm/msm/adreno/a6xx_gmu.h
index d3f6cd8b9741..b9e966e602e2 100644
--- a/drivers/gpu/drm/msm/adreno/a6xx_gmu.h
+++ b/drivers/gpu/drm/msm/adreno/a6xx_gmu.h
@@ -239,6 +239,7 @@ bool a6xx_gmu_gx_is_on(struct adreno_gpu *adreno_gpu);
 bool a7xx_gmu_gx_is_on(struct adreno_gpu *adreno_gpu);
 bool a8xx_gmu_gx_is_on(struct adreno_gpu *adreno_gpu);
 bool a6xx_gmu_sptprac_is_on(struct a6xx_gmu *gmu);
+bool a6xx_gmu_scales_bw(struct a6xx_gmu *gmu);
 void a6xx_sptprac_disable(struct a6xx_gmu *gmu);
 int a6xx_sptprac_enable(struct a6xx_gmu *gmu);
 
diff --git a/drivers/gpu/drm/msm/adreno/a6xx_hfi.c b/drivers/gpu/drm/msm/adreno/a6xx_hfi.c
index 6b34e704a70d..ac684d72d2b4 100644
--- a/drivers/gpu/drm/msm/adreno/a6xx_hfi.c
+++ b/drivers/gpu/drm/msm/adreno/a6xx_hfi.c
@@ -810,7 +810,7 @@ static int a6xx_hfi_send_bw_table(struct a6xx_gmu *gmu)
 	if (!msg)
 		return -ENOMEM;
 
-	if (info->bcms && gmu->nr_gpu_bws > 1)
+	if (a6xx_gmu_scales_bw(gmu))
 		a6xx_generate_bw_table(info, gmu, msg);
 	else if (adreno_is_a618(adreno_gpu))
 		a618_build_bw_table(msg);

-- 
2.55.0