[PATCH v2] drm/amdgpu: Read vram width from integrated system info table

Kai Wasserbäch kai at dev.carbon-project.org
Mon Apr 3 15:20:23 UTC 2017


Dear Harry,
Harry Wentland wrote on 03.04.2017 17:01:
> On KB, KV, CZ we should read the vram width from integrated system
> table, if we can. The NOOFCHAN in MC_SHARED_CHMAP is not accurate.
> 
> With this change we can enable two 4k displays on CZ again. This use
> case was broken sometime in January when we started looking at
> vram_width for bandwidth calculations instead of hardcoding this value.
> 
> v2:
>   Return 0 if integrated system info table is not available.
> 
> Tested-by: Roman Li <roman.li at amd.com>
> Signed-off-by: Harry Wentland <harry.wentland at amd.com>
> ---
>  drivers/gpu/drm/amd/amdgpu/amdgpu_atombios.c | 29 ++++++++++
>  drivers/gpu/drm/amd/amdgpu/amdgpu_atombios.h |  2 +
>  drivers/gpu/drm/amd/amdgpu/gmc_v7_0.c        | 87 +++++++++++++++-------------
>  drivers/gpu/drm/amd/amdgpu/gmc_v8_0.c        | 87 +++++++++++++++-------------
>  4 files changed, 123 insertions(+), 82 deletions(-)
> 
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_atombios.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_atombios.c
> index f52b1bf3d3d9..ad4329922f79 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_atombios.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_atombios.c
> @@ -754,6 +754,35 @@ union igp_info {
>  	struct _ATOM_INTEGRATED_SYSTEM_INFO_V1_9 info_9;
>  };
>  
> +/*
> + * Return vram width from integrated system info table, if available,
> + * or 0 if not.
> + */
> +int amdgpu_atombios_get_vram_width(struct amdgpu_device *adev)
> +{
> +	struct amdgpu_mode_info *mode_info = &adev->mode_info;
> +	int index = GetIndexIntoMasterTable(DATA, IntegratedSystemInfo);
> +	u16 data_offset, size;
> +	union igp_info *igp_info;
> +	u8 frev, crev;
> +
> +	/* get any igp specific overrides */
> +	if (amdgpu_atom_parse_data_header(mode_info->atom_context, index, &size,
> +				   &frev, &crev, &data_offset)) {
> +		igp_info = (union igp_info *)
> +			(mode_info->atom_context->bios + data_offset);
> +		switch (crev) {
> +		case 8:
> +		case 9:
> +			return igp_info->info_8.ucUMAChannelNumber * 64;
> +		default:
> +			return 0;
> +		}
> +	}
> +
> +	return 0;
> +}
> +
>  static void amdgpu_atombios_get_igp_ss_overrides(struct amdgpu_device *adev,
>  						 struct amdgpu_atom_ss *ss,
>  						 int id)
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_atombios.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_atombios.h
> index 4e0f488487f3..38d0fe32e5cd 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_atombios.h
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_atombios.h
> @@ -148,6 +148,8 @@ int amdgpu_atombios_get_clock_info(struct amdgpu_device *adev);
>  
>  int amdgpu_atombios_get_gfx_info(struct amdgpu_device *adev);
>  
> +int amdgpu_atombios_get_vram_width(struct amdgpu_device *adev);
> +
>  bool amdgpu_atombios_get_asic_ss_info(struct amdgpu_device *adev,
>  				      struct amdgpu_atom_ss *ss,
>  				      int id, u32 clock);
> diff --git a/drivers/gpu/drm/amd/amdgpu/gmc_v7_0.c b/drivers/gpu/drm/amd/amdgpu/gmc_v7_0.c
> index 0c0a6015cca5..78643a1baa5c 100644
> --- a/drivers/gpu/drm/amd/amdgpu/gmc_v7_0.c
> +++ b/drivers/gpu/drm/amd/amdgpu/gmc_v7_0.c
> @@ -37,6 +37,8 @@
>  #include "oss/oss_2_0_d.h"
>  #include "oss/oss_2_0_sh_mask.h"
>  
> +#include "amdgpu_atombios.h"
> +
>  static void gmc_v7_0_set_gart_funcs(struct amdgpu_device *adev);
>  static void gmc_v7_0_set_irq_funcs(struct amdgpu_device *adev);
>  static int gmc_v7_0_wait_for_idle(void *handle);
> @@ -325,48 +327,51 @@ static void gmc_v7_0_mc_program(struct amdgpu_device *adev)
>   */
>  static int gmc_v7_0_mc_init(struct amdgpu_device *adev)
>  {
> -	u32 tmp;
> -	int chansize, numchan;
> -
> -	/* Get VRAM informations */
> -	tmp = RREG32(mmMC_ARB_RAMCFG);
> -	if (REG_GET_FIELD(tmp, MC_ARB_RAMCFG, CHANSIZE)) {
> -		chansize = 64;
> -	} else {
> -		chansize = 32;
> -	}
> -	tmp = RREG32(mmMC_SHARED_CHMAP);
> -	switch (REG_GET_FIELD(tmp, MC_SHARED_CHMAP, NOOFCHAN)) {
> -	case 0:
> -	default:
> -		numchan = 1;
> -		break;
> -	case 1:
> -		numchan = 2;
> -		break;
> -	case 2:
> -		numchan = 4;
> -		break;
> -	case 3:
> -		numchan = 8;
> -		break;
> -	case 4:
> -		numchan = 3;
> -		break;
> -	case 5:
> -		numchan = 6;
> -		break;
> -	case 6:
> -		numchan = 10;
> -		break;
> -	case 7:
> -		numchan = 12;
> -		break;
> -	case 8:
> -		numchan = 16;
> -		break;
> +	adev->mc.vram_width = amdgpu_atombios_get_vram_width(adev);
> +	if (!adev->mc.vram_width) {
> +		u32 tmp;
> +		int chansize, numchan;
> +
> +		/* Get VRAM informations */
> +		tmp = RREG32(mmMC_ARB_RAMCFG);
> +		if (REG_GET_FIELD(tmp, MC_ARB_RAMCFG, CHANSIZE)) {
> +			chansize = 64;
> +		} else {
> +			chansize = 32;
> +		}
> +		tmp = RREG32(mmMC_SHARED_CHMAP);
> +		switch (REG_GET_FIELD(tmp, MC_SHARED_CHMAP, NOOFCHAN)) {
> +		case 0:
> +		default:
> +			numchan = 1;
> +			break;
> +		case 1:
> +			numchan = 2;
> +			break;
> +		case 2:
> +			numchan = 4;
> +			break;
> +		case 3:
> +			numchan = 8;
> +			break;
> +		case 4:
> +			numchan = 3;
> +			break;
> +		case 5:
> +			numchan = 6;
> +			break;
> +		case 6:
> +			numchan = 10;
> +			break;
> +		case 7:
> +			numchan = 12;
> +			break;
> +		case 8:
> +			numchan = 16;
> +			break;
> +		}
> +		adev->mc.vram_width = numchan * chansize;
>  	}
> -	adev->mc.vram_width = numchan * chansize;
>  	/* Could aper size report 0 ? */
>  	adev->mc.aper_base = pci_resource_start(adev->pdev, 0);
>  	adev->mc.aper_size = pci_resource_len(adev->pdev, 0);
> diff --git a/drivers/gpu/drm/amd/amdgpu/gmc_v8_0.c b/drivers/gpu/drm/amd/amdgpu/gmc_v8_0.c
> index d19d1c5e2847..42b2f357a799 100644
> --- a/drivers/gpu/drm/amd/amdgpu/gmc_v8_0.c
> +++ b/drivers/gpu/drm/amd/amdgpu/gmc_v8_0.c
> @@ -38,6 +38,8 @@
>  #include "vid.h"
>  #include "vi.h"
>  
> +#include "amdgpu_atombios.h"
> +
>  
>  static void gmc_v8_0_set_gart_funcs(struct amdgpu_device *adev);
>  static void gmc_v8_0_set_irq_funcs(struct amdgpu_device *adev);
> @@ -487,48 +489,51 @@ static void gmc_v8_0_mc_program(struct amdgpu_device *adev)
>   */
>  static int gmc_v8_0_mc_init(struct amdgpu_device *adev)
>  {
> -	u32 tmp;
> -	int chansize, numchan;
> -
> -	/* Get VRAM informations */
> -	tmp = RREG32(mmMC_ARB_RAMCFG);
> -	if (REG_GET_FIELD(tmp, MC_ARB_RAMCFG, CHANSIZE)) {
> -		chansize = 64;
> -	} else {
> -		chansize = 32;
> -	}
> -	tmp = RREG32(mmMC_SHARED_CHMAP);
> -	switch (REG_GET_FIELD(tmp, MC_SHARED_CHMAP, NOOFCHAN)) {
> -	case 0:
> -	default:
> -		numchan = 1;
> -		break;
> -	case 1:
> -		numchan = 2;
> -		break;
> -	case 2:
> -		numchan = 4;
> -		break;
> -	case 3:
> -		numchan = 8;
> -		break;
> -	case 4:
> -		numchan = 3;
> -		break;
> -	case 5:
> -		numchan = 6;
> -		break;
> -	case 6:
> -		numchan = 10;
> -		break;
> -	case 7:
> -		numchan = 12;
> -		break;
> -	case 8:
> -		numchan = 16;
> -		break;
> +	adev->mc.vram_width = amdgpu_atombios_get_vram_width(adev);
> +	if (!adev->mc.vram_width) {
> +		u32 tmp;
> +		int chansize, numchan;
> +
> +		/* Get VRAM informations */
> +		tmp = RREG32(mmMC_ARB_RAMCFG);
> +		if (REG_GET_FIELD(tmp, MC_ARB_RAMCFG, CHANSIZE)) {
> +			chansize = 64;
> +		} else {
> +			chansize = 32;
> +		}
> +		tmp = RREG32(mmMC_SHARED_CHMAP);
> +		switch (REG_GET_FIELD(tmp, MC_SHARED_CHMAP, NOOFCHAN)) {
> +		case 0:
> +		default:
> +			numchan = 1;
> +			break;
> +		case 1:
> +			numchan = 2;
> +			break;
> +		case 2:
> +			numchan = 4;
> +			break;
> +		case 3:
> +			numchan = 8;
> +			break;
> +		case 4:
> +			numchan = 3;
> +			break;
> +		case 5:
> +			numchan = 6;
> +			break;
> +		case 6:
> +			numchan = 10;
> +			break;
> +		case 7:
> +			numchan = 12;
> +			break;
> +		case 8:
> +			numchan = 16;
> +			break;
> +		}
> +		adev->mc.vram_width = numchan * chansize;

I might miss something subtle here, but after reading this a couple of times,
I've convinced myself this is exactly the same switch statement as in
gmc_v7_0_mc_init() above, right? If so: why not move that part to common code as
well?

Cheers,
Kai


>  	}
> -	adev->mc.vram_width = numchan * chansize;
>  	/* Could aper size report 0 ? */
>  	adev->mc.aper_base = pci_resource_start(adev->pdev, 0);
>  	adev->mc.aper_size = pci_resource_len(adev->pdev, 0);


-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 659 bytes
Desc: OpenPGP digital signature
URL: <https://lists.freedesktop.org/archives/amd-gfx/attachments/20170403/322713ee/attachment-0001.sig>


More information about the amd-gfx mailing list