From c256af0d6c1846db9af357a913b277b566ca3797 Mon Sep 17 00:00:00 2001 From: Matt Roper Date: Tue, 20 Apr 2021 14:18:42 +0100 Subject: [PATCH] drm/i915/lmem: Fail driver init if LMEM training failed Boot firmware performs memory training and health assessment during startup. If the memory training fails, the firmware will consider the GPU unusable and will instruct the punit to keep the GT powered down. If this happens, our driver will be unable to communicate with the GT (all GT registers will read back as 0, forcewake requests will timeout, etc.) so we should abort driver initialization if this happens. We can confirm that LMEM was initialized successfully via sgunit register GU_CNTL. Bspec: 53111 Signed-off-by: Matt Roper Cc: Caz Yokoyama Reviewed-by: Matthew Auld Signed-off-by: Matthew Auld Link: https://patchwork.freedesktop.org/patch/msgid/20210420131842.164163-5-matthew.auld@intel.com --- drivers/gpu/drm/i915/i915_reg.h | 3 +++ drivers/gpu/drm/i915/intel_uncore.c | 12 ++++++++++++ 2 files changed, 15 insertions(+) diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h index e087bcd21911..f41474913d27 100644 --- a/drivers/gpu/drm/i915/i915_reg.h +++ b/drivers/gpu/drm/i915/i915_reg.h @@ -487,6 +487,9 @@ static inline bool i915_mmio_reg_valid(i915_reg_t reg) #define GAB_CTL _MMIO(0x24000) #define GAB_CTL_CONT_AFTER_PAGEFAULT (1 << 8) +#define GU_CNTL _MMIO(0x101010) +#define LMEM_INIT REG_BIT(7) + #define GEN6_STOLEN_RESERVED _MMIO(0x1082C0) #define GEN6_STOLEN_RESERVED_ADDR_MASK (0xFFF << 20) #define GEN7_STOLEN_RESERVED_ADDR_MASK (0x3FFF << 18) diff --git a/drivers/gpu/drm/i915/intel_uncore.c b/drivers/gpu/drm/i915/intel_uncore.c index ed5abe7be498..b4aaf8b7109f 100644 --- a/drivers/gpu/drm/i915/intel_uncore.c +++ b/drivers/gpu/drm/i915/intel_uncore.c @@ -1917,6 +1917,18 @@ int intel_uncore_init_mmio(struct intel_uncore *uncore) if (ret) return ret; + /* + * The boot firmware initializes local memory and assesses its health. + * If memory training fails, the punit will have been instructed to + * keep the GT powered down; we won't be able to communicate with it + * and we should not continue with driver initialization. + */ + if (IS_DGFX(i915) && + !(__raw_uncore_read32(uncore, GU_CNTL) & LMEM_INIT)) { + drm_err(&i915->drm, "LMEM not initialized by firmware\n"); + return -ENODEV; + } + if (INTEL_GEN(i915) > 5 && !intel_vgpu_active(i915)) uncore->flags |= UNCORE_HAS_FORCEWAKE; -- 2.11.0