Re: [PATCH] drm/radeon/kms/blit: fix blit copy for very large buffers

On Mit, 2012-02-01 at 17:07 -0500, Ilija Hadzic wrote:

diff --git a/drivers/gpu/drm/radeon/r600_blit_kms.c b/drivers/gpu/drm/radeon/r600_blit_kms.c index d996f43..32dcc95 100644 --- a/drivers/gpu/drm/radeon/r600_blit_kms.c +++ b/drivers/gpu/drm/radeon/r600_blit_kms.c @@ -468,27 +468,42 @@ set_default_state(struct radeon_device *rdev) radeon_ring_write(ring, sq_stack_resource_mgmt_2); }

+#define I2F_MAX_BITS 15 +#define I2F_MAX_INPUT ((2 << I2F_MAX_BITS) - 1)

Should be ((1 << I2F_MAX_BITS) - 1): 2^n == (1 << n)

static uint32_t i2f(uint32_t input) { u32 result, i, exponent, fraction;

• if ((input & 0x3fff) == 0)

• result = 0; /* 0 is a special case */
  

• WARN_ON(input > I2F_MAX_INPUT);

Use WARN_ON_ONCE here to avoid spamming the kernel output. If this is ever hit again, it won't happen just once.

Looks good to me otherwise.