[Intel-gfx] [PATCH] drm/i915/dmc: Add MMIO range restrictions

[Anusha Srivatsa]

Bspec has added some steps that check for DMC MMIO range before
programming them.

Cc: Lucas De Marchi <lucas.demarchi at intel.com>
Signed-off-by: Anusha Srivatsa <anusha.srivatsa at intel.com>
---
 drivers/gpu/drm/i915/display/intel_dmc.c | 42 ++++++++++++++++++++++++
 1 file changed, 42 insertions(+)

diff --git a/drivers/gpu/drm/i915/display/intel_dmc.c b/drivers/gpu/drm/i915/display/intel_dmc.c
index 257cf662f9f4..dc4ff43e9467 100644
--- a/drivers/gpu/drm/i915/display/intel_dmc.c
+++ b/drivers/gpu/drm/i915/display/intel_dmc.c
@@ -103,6 +103,18 @@ MODULE_FIRMWARE(BXT_DMC_PATH);
 #define DMC_V1_MAX_MMIO_COUNT		8
 #define DMC_V3_MAX_MMIO_COUNT		20
 #define DMC_V1_MMIO_START_RANGE		0x80000
+#define TGL_MAIN_MMIO_START		0x8F000
+#define TGL_MAIN_MMIO_END		0x8FFFF
+#define TGL_PIPEA_MMIO_START		0x92000
+#define TGL_PIPEA_MMIO_END		0x93FFF
+#define TGL_PIPEB_MMIO_START		0x96000
+#define TGL_PIPEB_MMIO_END		0x97FFF
+#define TGL_PIPEC_MMIO_START		0x9A000
+#define TGL_PIPEC_MMIO_END		0x9BFFF
+#define TGL_PIPED_MMIO_START		0x9E000
+#define TGL_PIPED_MMIO_END		0x9FFFF
+#define ADLP_PIPE_MMIO_START		0x5F000
+#define ADLP_PIPE_MMIO_END		0x5FFFF
 
 struct intel_css_header {
 	/* 0x09 for DMC */
@@ -374,6 +386,30 @@ static void dmc_set_fw_offset(struct intel_dmc *dmc,
 	}
 }
 
+static bool dmc_mmio_addr_sanity_check(struct intel_dmc *dmc, const u32 *mmioaddr,
+u32 mmio_count)
+{
+	struct drm_i915_private *i915 = container_of(dmc, typeof(*i915), dmc);
+	int i;
+
+	if (IS_DG2(i915) || IS_ALDERLAKE_P(i915)) {
+		for (i = 0; i < mmio_count; i++) {
+			if (!((mmioaddr[i] >= TGL_MAIN_MMIO_START && mmioaddr[i] <= TGL_MAIN_MMIO_END) ||
+			      (mmioaddr[i] >= ADLP_PIPE_MMIO_START && mmioaddr[i] <= ADLP_PIPE_MMIO_END)))
+				return false;
+		}
+	} else if (IS_TIGERLAKE(i915) || IS_DG1(i915) || IS_ALDERLAKE_S(i915))
+		for (i = 0; i < mmio_count; i++) {
+			if ((!(mmioaddr[i] >= TGL_MAIN_MMIO_START && mmioaddr[i] <= TGL_MAIN_MMIO_END) ||
+			      (mmioaddr[i] >= TGL_PIPEA_MMIO_START && mmioaddr[i] <= TGL_PIPEA_MMIO_END) ||
+			      (mmioaddr[i] >= TGL_PIPEB_MMIO_START && mmioaddr[i] <= TGL_PIPEB_MMIO_END) ||
+			      (mmioaddr[i] >= TGL_PIPEC_MMIO_START && mmioaddr[i] <= TGL_PIPEC_MMIO_END) ||
+			      (mmioaddr[i] >= TGL_PIPED_MMIO_START && mmioaddr[i] <= TGL_PIPEC_MMIO_END)))
+				return false;
+	}
+	return true;
+}
+
 static u32 parse_dmc_fw_header(struct intel_dmc *dmc,
 			       const struct intel_dmc_header_base *dmc_header,
 			       size_t rem_size, u8 dmc_id)
@@ -443,6 +479,12 @@ static u32 parse_dmc_fw_header(struct intel_dmc *dmc,
 		return 0;
 	}
 
+	if (dmc_header->header_ver == 3) {
+		if (!dmc_mmio_addr_sanity_check(dmc, mmioaddr, mmio_count))
+			drm_err(&i915->drm, "DMC firmware has Wrong MMIO Addresses\n");
+			return 0;
+	}
+
 	for (i = 0; i < mmio_count; i++) {
 		dmc_info->mmioaddr[i] = _MMIO(mmioaddr[i]);
 		dmc_info->mmiodata[i] = mmiodata[i];
-- 
2.25.1