Commit c0d6b616 authored by Lucas De Marchi's avatar Lucas De Marchi Committed by Rodrigo Vivi
Browse files

drm/xe: Carve out top of DSM as reserved 



Top of DSM contains the WOPCM where kernel driver shouldn't access as
it contains data from other HW agents. Carve it out from the stolen
memory. On a MTL system, the output now matches the expected values:

Reviewed-by: default avatarMatt Roper <matthew.d.roper@intel.com>
Link: https://lore.kernel.org/r/20230726160708.3967790-10-lucas.demarchi@intel.com


Signed-off-by: default avatarLucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: default avatarRodrigo Vivi <rodrigo.vivi@intel.com>
parent 58052eb7

drivers/gpu/drm/xe/regs/xe_regs.h

+3 −0
Original line number Diff line number Diff line
@@ -97,4 +97,7 @@ 
#define DSMBASE					XE_REG(0x1080C0)

#define   BDSM_MASK				REG_GENMASK64(63, 20)



#define STOLEN_RESERVED				XE_REG(0x1082c0)

#define   WOPCM_SIZE_MASK			REG_GENMASK64(8, 7)



#endif

drivers/gpu/drm/xe/xe_ttm_stolen_mgr.c

+7 −1
Original line number Diff line number Diff line
@@ -89,7 +89,7 @@ static s64 detect_bar2_dgfx(struct xe_device *xe, struct xe_ttm_stolen_mgr *mgr) 
static u32 detect_bar2_integrated(struct xe_device *xe, struct xe_ttm_stolen_mgr *mgr)

{

	struct pci_dev *pdev = to_pci_dev(xe->drm.dev);

	u32 stolen_size;

	u32 stolen_size, wopcm_size;

	u32 ggc, gms;



	ggc = xe_mmio_read32(xe_root_mmio_gt(xe), GGC);
@@ -124,6 +124,12 @@ static u32 detect_bar2_integrated(struct xe_device *xe, struct xe_ttm_stolen_mgr 
		return 0;

	}



	/* Carve out the top of DSM as it contains the reserved WOPCM region */

	wopcm_size = REG_FIELD_GET64(WOPCM_SIZE_MASK,

				     xe_mmio_read64(xe_root_mmio_gt(xe),

						    STOLEN_RESERVED));

	stolen_size -= (1U << wopcm_size) * SZ_1M;



	if (drm_WARN_ON(&xe->drm, stolen_size + SZ_8M > pci_resource_len(pdev, 2)))

		return 0;