[PATCH] gpu: drm: radeon: r600: Replace mdelay() and udelay() with msleep() and usleep_range()

From: Jia-Ju Bai
Date: Fri Aug 03 2018 - 20:21:19 EST


r600_gpu_soft_reset() and r600_gpu_pci_config_reset() are never
called in atomic context.
They call mdelay() and udelay() to busily wait, which is not necessary.
mdelay() and udelay() can be replaced with msleep() and usleep_range().

This is found by a static analysis tool named DCNS written by myself.

Signed-off-by: Jia-Ju Bai <baijiaju1990@xxxxxxxxx>
---
drivers/gpu/drm/radeon/r600.c | 16 ++++++++--------
1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/drivers/gpu/drm/radeon/r600.c b/drivers/gpu/drm/radeon/r600.c
index e06e2d8feab3..de5f6d9f251e 100644
--- a/drivers/gpu/drm/radeon/r600.c
+++ b/drivers/gpu/drm/radeon/r600.c
@@ -1705,7 +1705,7 @@ static void r600_gpu_soft_reset(struct radeon_device *rdev, u32 reset_mask)
WREG32(DMA_RB_CNTL, tmp);
}

- mdelay(50);
+ msleep(50);

rv515_mc_stop(rdev, &save);
if (r600_mc_wait_for_idle(rdev)) {
@@ -1782,7 +1782,7 @@ static void r600_gpu_soft_reset(struct radeon_device *rdev, u32 reset_mask)
WREG32(R_008020_GRBM_SOFT_RESET, tmp);
tmp = RREG32(R_008020_GRBM_SOFT_RESET);

- udelay(50);
+ usleep_range(50, 100);

tmp &= ~grbm_soft_reset;
WREG32(R_008020_GRBM_SOFT_RESET, tmp);
@@ -1796,7 +1796,7 @@ static void r600_gpu_soft_reset(struct radeon_device *rdev, u32 reset_mask)
WREG32(SRBM_SOFT_RESET, tmp);
tmp = RREG32(SRBM_SOFT_RESET);

- udelay(50);
+ usleep_range(50, 100);

tmp &= ~srbm_soft_reset;
WREG32(SRBM_SOFT_RESET, tmp);
@@ -1804,10 +1804,10 @@ static void r600_gpu_soft_reset(struct radeon_device *rdev, u32 reset_mask)
}

/* Wait a little for things to settle down */
- mdelay(1);
+ usleep_range(1000, 2000);

rv515_mc_resume(rdev, &save);
- udelay(50);
+ usleep_range(50, 100);

r600_print_gpu_status_regs(rdev);
}
@@ -1835,7 +1835,7 @@ static void r600_gpu_pci_config_reset(struct radeon_device *rdev)
tmp &= ~DMA_RB_ENABLE;
WREG32(DMA_RB_CNTL, tmp);

- mdelay(50);
+ msleep(50);

/* set mclk/sclk to bypass */
if (rdev->family >= CHIP_RV770)
@@ -1857,12 +1857,12 @@ static void r600_gpu_pci_config_reset(struct radeon_device *rdev)

/* reset */
radeon_pci_config_reset(rdev);
- mdelay(1);
+ usleep_range(1000, 2000);

/* BIF reset workaround. Not sure if this is needed on 6xx */
tmp = SOFT_RESET_BIF;
WREG32(SRBM_SOFT_RESET, tmp);
- mdelay(1);
+ usleep_range(1000, 2000);
WREG32(SRBM_SOFT_RESET, 0);

/* wait for asic to come out of reset */
--
2.17.0