[PATCH] drm/amdgpu: read reg in each iterate of psp_wait_for loop

[Deucher, Alexander]

> -----Original Message-----
> From: Junwei Zhang [mailto:Jerry.Zhang at amd.com]
> Sent: Monday, July 17, 2017 10:54 PM
> To: amd-gfx at lists.freedesktop.org
> Cc: Deucher, Alexander; Huang, Ray; gregkh at linuxfoundation.org; Zhang,
> Jerry; stable at vger.kernel.org
> Subject: [PATCH] drm/amdgpu: read reg in each iterate of psp_wait_for loop
> 
> From: "Zhang, Jerry" <Jerry.Zhang at amd.com>
> 
> v2: fixes the SOS loading failure for PSP v3.1
> 
> Signed-off-by: Junwei Zhang <Jerry.Zhang at amd.com>
> Cc: stable at vger.kernel.org
> Acked-by: Alex Deucher <alexander.deucher at amd.com> (v1)
> Acked-by: Huang Rui <ray.huang at amd.com> (v1)

Reviewed-by: Alex Deucher <alexander.deucher at amd.com>

> ---
>  drivers/gpu/drm/amd/amdgpu/amdgpu_psp.c | 3 +--
>  drivers/gpu/drm/amd/amdgpu/psp_v3_1.c   | 2 --
>  2 files changed, 1 insertion(+), 4 deletions(-)
> 
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_psp.c
> b/drivers/gpu/drm/amd/amdgpu/amdgpu_psp.c
> index c919579..644941d 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_psp.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_psp.c
> @@ -98,9 +98,8 @@ int psp_wait_for(struct psp_context *psp, uint32_t
> reg_index,
>  	int i;
>  	struct amdgpu_device *adev = psp->adev;
> 
> -	val = RREG32(reg_index);
> -
>  	for (i = 0; i < adev->usec_timeout; i++) {
> +		val = RREG32(reg_index);
>  		if (check_changed) {
>  			if (val != reg_val)
>  				return 0;
> diff --git a/drivers/gpu/drm/amd/amdgpu/psp_v3_1.c
> b/drivers/gpu/drm/amd/amdgpu/psp_v3_1.c
> index 2718e86..23106e3 100644
> --- a/drivers/gpu/drm/amd/amdgpu/psp_v3_1.c
> +++ b/drivers/gpu/drm/amd/amdgpu/psp_v3_1.c
> @@ -237,11 +237,9 @@ int psp_v3_1_bootloader_load_sos(struct
> psp_context *psp)
> 
>  	/* there might be handshake issue with hardware which needs delay
> */
>  	mdelay(20);
> -#if 0
>  	ret = psp_wait_for(psp, SOC15_REG_OFFSET(MP0, 0,
> mmMP0_SMN_C2PMSG_81),
>  			   RREG32_SOC15(MP0, 0,
> mmMP0_SMN_C2PMSG_81),
>  			   0, true);
> -#endif
> 
>  	return ret;
>  }
> --
> 1.9.1