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

[Anusha Srivatsa <anusha.srivatsa@intel.com>]

Bspec has added some steps that check forDMC MMIO range before
programming them

v2: Fix for CI
v3: move register defines to .h (Anusha)
- Check MMIO restrictions per pipe
- Add MMIO restricton for v1 dmc header as well (Lucas)
v4: s/_PICK/_PICK_EVEN and use it only for Pipe DMC scenario.
- clean up sanity check logic.(Lucas)

BSpec: 49193

Cc: <stable@vger.kernel.org>
Cc: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: Anusha Srivatsa <anusha.srivatsa@intel.com>
---
 drivers/gpu/drm/i915/display/intel_dmc.c      | 42 +++++++++++++++++++
 drivers/gpu/drm/i915/display/intel_dmc_regs.h | 18 +++++++-
 2 files changed, 59 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/display/intel_dmc.c b/drivers/gpu/drm/i915/display/intel_dmc.c
index 257cf662f9f4..7abe4418eeb0 100644
--- a/drivers/gpu/drm/i915/display/intel_dmc.c
+++ b/drivers/gpu/drm/i915/display/intel_dmc.c
@@ -374,6 +374,43 @@ 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, int header_ver, u8 dmc_id)
+{
+	struct drm_i915_private *i915 = container_of(dmc, typeof(*i915), dmc);
+	u32 start_range, end_range;
+	int i;
+
+	if (dmc_id >= DMC_FW_MAX || dmc_id < DMC_FW_MAIN) {
+		drm_warn(&i915->drm, "Unsupported firmware id %u\n", dmc_id);
+		return false;
+	}
+
+	if (header_ver == 1) {
+		start_range = DMC_MMIO_START_RANGE;
+		end_range = DMC_MMIO_END_RANGE;
+	} else if (dmc_id == DMC_FW_MAIN) {
+		start_range = TGL_MAIN_MMIO_START;
+		end_range = TGL_MAIN_MMIO_END;
+	} else if (IS_DG2(i915) || IS_ALDERLAKE_P(i915)) {
+		start_range = ADLP_PIPE_MMIO_START;
+		end_range = ADLP_PIPE_MMIO_END;
+	} else if (IS_TIGERLAKE(i915) || IS_DG1(i915) || IS_ALDERLAKE_S(i915)) {
+		start_range = TGL_PIPE_MMIO_START(dmc_id);
+		end_range = TGL_PIPE_MMIO_END(dmc_id);
+	} else {
+		drm_warn(&i915->drm, "Unknown mmio range for sanity check");
+		return false;
+	}
+
+	for (i = 0; i < mmio_count; i++) {
+		if (mmioaddr[i] < start_range || mmioaddr[i] > end_range)
+			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 +480,11 @@ static u32 parse_dmc_fw_header(struct intel_dmc *dmc,
 		return 0;
 	}
 
+	if (!dmc_mmio_addr_sanity_check(dmc, mmioaddr, mmio_count, dmc_header->header_ver, dmc_id)) {
+		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];
diff --git a/drivers/gpu/drm/i915/display/intel_dmc_regs.h b/drivers/gpu/drm/i915/display/intel_dmc_regs.h
index d65e698832eb..67e14eb96a7a 100644
--- a/drivers/gpu/drm/i915/display/intel_dmc_regs.h
+++ b/drivers/gpu/drm/i915/display/intel_dmc_regs.h
@@ -16,7 +16,23 @@
 #define DMC_LAST_WRITE		_MMIO(0x8F034)
 #define DMC_LAST_WRITE_VALUE	0xc003b400
 #define DMC_MMIO_START_RANGE	0x80000
-#define DMC_MMIO_END_RANGE	0x8FFFF
+#define DMC_MMIO_END_RANGE     0x8FFFF
+#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 ADLP_PIPE_MMIO_START		0x5F000
+#define ADLP_PIPE_MMIO_END		0x5FFFF
+
+#define TGL_PIPE_MMIO_START(dmc_id)	_PICK_EVEN(((dmc_id) - 1), _TGL_PIPEA_MMIO_START,\
+					      _TGL_PIPEB_MMIO_START)
+
+#define TGL_PIPE_MMIO_END(dmc_id)	_PICK_EVEN(((dmc_id) - 1), _TGL_PIPEA_MMIO_END,\
+					      _TGL_PIPEB_MMIO_END)
+
 #define SKL_DMC_DC3_DC5_COUNT	_MMIO(0x80030)
 #define SKL_DMC_DC5_DC6_COUNT	_MMIO(0x8002C)
 #define BXT_DMC_DC3_DC5_COUNT	_MMIO(0x80038)
-- 
2.25.1