From 4046217954d4e79d57d34c56ce42dec4f87e2ce9 Mon Sep 17 00:00:00 2001
From: Philipp Zabel
Date: Mon, 9 Oct 2017 12:03:30 +0200
Subject: [PATCH] drm/etnaviv: reduce reset delay
After reset assertion, we only have to wait for the reset signals to
propagate through the GPU before deasserting the reset again. A few
hundred clock cycles should be more than enough. Replace the msleep(1),
which can actually take about 30 ms on i.MX6Q in some configurations,
with an usleep_range of a few microseconds. If the delay was too short,
the FE would not be idle afterwards, and the reset would be retried.
Signed-off-by: Philipp Zabel
Signed-off-by: Lucas Stach
---
drivers/gpu/drm/etnaviv/etnaviv_gpu.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gpu.c b/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
index 3e0fcc1fafb5..95ee479c95cb 100644
--- a/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
+++ b/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
@@ -456,7 +456,7 @@ static int etnaviv_hw_reset(struct etnaviv_gpu *gpu)
gpu_write(gpu, VIVS_HI_CLOCK_CONTROL, control);
/* wait for reset. */
- msleep(1);
+ usleep_range(10, 20);
/* reset soft reset bit. */
control &= ~VIVS_HI_CLOCK_CONTROL_SOFT_RESET;