[PATCH 5.11 03/45] drm/msm: a6xx: Make sure the SQE microcode is safe

From: Greg Kroah-Hartman
Date: Fri Apr 09 2021 - 06:13:13 EST


From: Jordan Crouse <jcrouse@xxxxxxxxxxxxxx>

[ Upstream commit 8490f02a3ca45fd1bbcadc243b4db9b69d0e3450 ]

Most a6xx targets have security issues that were fixed with new versions
of the microcode(s). Make sure that we are booting with a safe version of
the microcode for the target and print a message and error if not.

v2: Add more informative error messages and fix typos

Signed-off-by: Jordan Crouse <jcrouse@xxxxxxxxxxxxxx>
Reviewed-by: Akhil P Oommen <akhilpo@xxxxxxxxxxxxxx>
Signed-off-by: Rob Clark <robdclark@xxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/gpu/drm/msm/adreno/a6xx_gpu.c | 77 ++++++++++++++++++++++-----
1 file changed, 64 insertions(+), 13 deletions(-)

diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
index 0366419d8bfe..e7a8442b59af 100644
--- a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
+++ b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
@@ -521,28 +521,73 @@ static int a6xx_cp_init(struct msm_gpu *gpu)
return a6xx_idle(gpu, ring) ? 0 : -EINVAL;
}

-static void a6xx_ucode_check_version(struct a6xx_gpu *a6xx_gpu,
+/*
+ * Check that the microcode version is new enough to include several key
+ * security fixes. Return true if the ucode is safe.
+ */
+static bool a6xx_ucode_check_version(struct a6xx_gpu *a6xx_gpu,
struct drm_gem_object *obj)
{
+ struct adreno_gpu *adreno_gpu = &a6xx_gpu->base;
+ struct msm_gpu *gpu = &adreno_gpu->base;
u32 *buf = msm_gem_get_vaddr(obj);
+ bool ret = false;

if (IS_ERR(buf))
- return;
+ return false;

/*
- * If the lowest nibble is 0xa that is an indication that this microcode
- * has been patched. The actual version is in dword [3] but we only care
- * about the patchlevel which is the lowest nibble of dword [3]
- *
- * Otherwise check that the firmware is greater than or equal to 1.90
- * which was the first version that had this fix built in
+ * Targets up to a640 (a618, a630 and a640) need to check for a
+ * microcode version that is patched to support the whereami opcode or
+ * one that is new enough to include it by default.
*/
- if (((buf[0] & 0xf) == 0xa) && (buf[2] & 0xf) >= 1)
- a6xx_gpu->has_whereami = true;
- else if ((buf[0] & 0xfff) > 0x190)
- a6xx_gpu->has_whereami = true;
+ if (adreno_is_a618(adreno_gpu) || adreno_is_a630(adreno_gpu) ||
+ adreno_is_a640(adreno_gpu)) {
+ /*
+ * If the lowest nibble is 0xa that is an indication that this
+ * microcode has been patched. The actual version is in dword
+ * [3] but we only care about the patchlevel which is the lowest
+ * nibble of dword [3]
+ *
+ * Otherwise check that the firmware is greater than or equal
+ * to 1.90 which was the first version that had this fix built
+ * in
+ */
+ if ((((buf[0] & 0xf) == 0xa) && (buf[2] & 0xf) >= 1) ||
+ (buf[0] & 0xfff) >= 0x190) {
+ a6xx_gpu->has_whereami = true;
+ ret = true;
+ goto out;
+ }

+ DRM_DEV_ERROR(&gpu->pdev->dev,
+ "a630 SQE ucode is too old. Have version %x need at least %x\n",
+ buf[0] & 0xfff, 0x190);
+ } else {
+ /*
+ * a650 tier targets don't need whereami but still need to be
+ * equal to or newer than 1.95 for other security fixes
+ */
+ if (adreno_is_a650(adreno_gpu)) {
+ if ((buf[0] & 0xfff) >= 0x195) {
+ ret = true;
+ goto out;
+ }
+
+ DRM_DEV_ERROR(&gpu->pdev->dev,
+ "a650 SQE ucode is too old. Have version %x need at least %x\n",
+ buf[0] & 0xfff, 0x195);
+ }
+
+ /*
+ * When a660 is added those targets should return true here
+ * since those have all the critical security fixes built in
+ * from the start
+ */
+ }
+out:
msm_gem_put_vaddr(obj);
+ return ret;
}

static int a6xx_ucode_init(struct msm_gpu *gpu)
@@ -565,7 +610,13 @@ static int a6xx_ucode_init(struct msm_gpu *gpu)
}

msm_gem_object_set_name(a6xx_gpu->sqe_bo, "sqefw");
- a6xx_ucode_check_version(a6xx_gpu, a6xx_gpu->sqe_bo);
+ if (!a6xx_ucode_check_version(a6xx_gpu, a6xx_gpu->sqe_bo)) {
+ msm_gem_unpin_iova(a6xx_gpu->sqe_bo, gpu->aspace);
+ drm_gem_object_put(a6xx_gpu->sqe_bo);
+
+ a6xx_gpu->sqe_bo = NULL;
+ return -EPERM;
+ }
}

gpu_write64(gpu, REG_A6XX_CP_SQE_INSTR_BASE_LO,
--
2.30.2