mirror of https://github.com/hak5/openwrt.git
201 lines
6.2 KiB
Diff
201 lines
6.2 KiB
Diff
From ba3aa9ce57cb933203cb0ebaa7c00ef756e5f84e Mon Sep 17 00:00:00 2001
|
|
From: Eric Anholt <eric@anholt.net>
|
|
Date: Sat, 2 Jul 2016 10:10:24 -0700
|
|
Subject: [PATCH] drm/vc4: Add a bitmap of branch targets during shader
|
|
validation.
|
|
|
|
This isn't used yet, it's just a first step toward loop validation.
|
|
During the main parsing of instructions, we need to know when we hit a
|
|
new basic block so that we can reset validated state.
|
|
|
|
v2: Fix a stray semicolon after an if block. (caught by kbuild test).
|
|
|
|
Signed-off-by: Eric Anholt <eric@anholt.net>
|
|
(cherry picked from commit 93aa9ae3e5523e49e4e5abacd4dbee0e4ab2d931)
|
|
---
|
|
drivers/gpu/drm/vc4/vc4_qpu_defines.h | 12 +++
|
|
drivers/gpu/drm/vc4/vc4_validate_shaders.c | 114 ++++++++++++++++++++++++++++-
|
|
2 files changed, 124 insertions(+), 2 deletions(-)
|
|
|
|
--- a/drivers/gpu/drm/vc4/vc4_qpu_defines.h
|
|
+++ b/drivers/gpu/drm/vc4/vc4_qpu_defines.h
|
|
@@ -230,6 +230,15 @@ enum qpu_unpack_r4 {
|
|
#define QPU_COND_MUL_SHIFT 46
|
|
#define QPU_COND_MUL_MASK QPU_MASK(48, 46)
|
|
|
|
+#define QPU_BRANCH_COND_SHIFT 52
|
|
+#define QPU_BRANCH_COND_MASK QPU_MASK(55, 52)
|
|
+
|
|
+#define QPU_BRANCH_REL ((uint64_t)1 << 51)
|
|
+#define QPU_BRANCH_REG ((uint64_t)1 << 50)
|
|
+
|
|
+#define QPU_BRANCH_RADDR_A_SHIFT 45
|
|
+#define QPU_BRANCH_RADDR_A_MASK QPU_MASK(49, 45)
|
|
+
|
|
#define QPU_SF ((uint64_t)1 << 45)
|
|
|
|
#define QPU_WADDR_ADD_SHIFT 38
|
|
@@ -261,4 +270,7 @@ enum qpu_unpack_r4 {
|
|
#define QPU_OP_ADD_SHIFT 24
|
|
#define QPU_OP_ADD_MASK QPU_MASK(28, 24)
|
|
|
|
+#define QPU_BRANCH_TARGET_SHIFT 0
|
|
+#define QPU_BRANCH_TARGET_MASK QPU_MASK(31, 0)
|
|
+
|
|
#endif /* VC4_QPU_DEFINES_H */
|
|
--- a/drivers/gpu/drm/vc4/vc4_validate_shaders.c
|
|
+++ b/drivers/gpu/drm/vc4/vc4_validate_shaders.c
|
|
@@ -59,6 +59,13 @@ struct vc4_shader_validation_state {
|
|
*/
|
|
uint32_t live_min_clamp_offsets[32 + 32 + 4];
|
|
bool live_max_clamp_regs[32 + 32 + 4];
|
|
+
|
|
+ /* Bitfield of which IPs are used as branch targets.
|
|
+ *
|
|
+ * Used for validation that the uniform stream is updated at the right
|
|
+ * points and clearing the texturing/clamping state.
|
|
+ */
|
|
+ unsigned long *branch_targets;
|
|
};
|
|
|
|
static uint32_t
|
|
@@ -418,13 +425,104 @@ check_instruction_reads(uint64_t inst,
|
|
return true;
|
|
}
|
|
|
|
+/* Make sure that all branches are absolute and point within the shader, and
|
|
+ * note their targets for later.
|
|
+ */
|
|
+static bool
|
|
+vc4_validate_branches(struct vc4_shader_validation_state *validation_state)
|
|
+{
|
|
+ uint32_t max_branch_target = 0;
|
|
+ bool found_shader_end = false;
|
|
+ int ip;
|
|
+ int shader_end_ip = 0;
|
|
+ int last_branch = -2;
|
|
+
|
|
+ for (ip = 0; ip < validation_state->max_ip; ip++) {
|
|
+ uint64_t inst = validation_state->shader[ip];
|
|
+ int32_t branch_imm = QPU_GET_FIELD(inst, QPU_BRANCH_TARGET);
|
|
+ uint32_t sig = QPU_GET_FIELD(inst, QPU_SIG);
|
|
+ uint32_t after_delay_ip = ip + 4;
|
|
+ uint32_t branch_target_ip;
|
|
+
|
|
+ if (sig == QPU_SIG_PROG_END) {
|
|
+ shader_end_ip = ip;
|
|
+ found_shader_end = true;
|
|
+ continue;
|
|
+ }
|
|
+
|
|
+ if (sig != QPU_SIG_BRANCH)
|
|
+ continue;
|
|
+
|
|
+ if (ip - last_branch < 4) {
|
|
+ DRM_ERROR("Branch at %d during delay slots\n", ip);
|
|
+ return false;
|
|
+ }
|
|
+ last_branch = ip;
|
|
+
|
|
+ if (inst & QPU_BRANCH_REG) {
|
|
+ DRM_ERROR("branching from register relative "
|
|
+ "not supported\n");
|
|
+ return false;
|
|
+ }
|
|
+
|
|
+ if (!(inst & QPU_BRANCH_REL)) {
|
|
+ DRM_ERROR("relative branching required\n");
|
|
+ return false;
|
|
+ }
|
|
+
|
|
+ /* The actual branch target is the instruction after the delay
|
|
+ * slots, plus whatever byte offset is in the low 32 bits of
|
|
+ * the instruction. Make sure we're not branching beyond the
|
|
+ * end of the shader object.
|
|
+ */
|
|
+ if (branch_imm % sizeof(inst) != 0) {
|
|
+ DRM_ERROR("branch target not aligned\n");
|
|
+ return false;
|
|
+ }
|
|
+
|
|
+ branch_target_ip = after_delay_ip + (branch_imm >> 3);
|
|
+ if (branch_target_ip >= validation_state->max_ip) {
|
|
+ DRM_ERROR("Branch at %d outside of shader (ip %d/%d)\n",
|
|
+ ip, branch_target_ip,
|
|
+ validation_state->max_ip);
|
|
+ return false;
|
|
+ }
|
|
+ set_bit(branch_target_ip, validation_state->branch_targets);
|
|
+
|
|
+ /* Make sure that the non-branching path is also not outside
|
|
+ * the shader.
|
|
+ */
|
|
+ if (after_delay_ip >= validation_state->max_ip) {
|
|
+ DRM_ERROR("Branch at %d continues past shader end "
|
|
+ "(%d/%d)\n",
|
|
+ ip, after_delay_ip, validation_state->max_ip);
|
|
+ return false;
|
|
+ }
|
|
+ set_bit(after_delay_ip, validation_state->branch_targets);
|
|
+ max_branch_target = max(max_branch_target, after_delay_ip);
|
|
+
|
|
+ /* There are two delay slots after program end is signaled
|
|
+ * that are still executed, then we're finished.
|
|
+ */
|
|
+ if (found_shader_end && ip == shader_end_ip + 2)
|
|
+ break;
|
|
+ }
|
|
+
|
|
+ if (max_branch_target > shader_end_ip) {
|
|
+ DRM_ERROR("Branch landed after QPU_SIG_PROG_END");
|
|
+ return false;
|
|
+ }
|
|
+
|
|
+ return true;
|
|
+}
|
|
+
|
|
struct vc4_validated_shader_info *
|
|
vc4_validate_shader(struct drm_gem_cma_object *shader_obj)
|
|
{
|
|
bool found_shader_end = false;
|
|
int shader_end_ip = 0;
|
|
uint32_t ip;
|
|
- struct vc4_validated_shader_info *validated_shader;
|
|
+ struct vc4_validated_shader_info *validated_shader = NULL;
|
|
struct vc4_shader_validation_state validation_state;
|
|
int i;
|
|
|
|
@@ -437,9 +535,18 @@ vc4_validate_shader(struct drm_gem_cma_o
|
|
for (i = 0; i < ARRAY_SIZE(validation_state.live_min_clamp_offsets); i++)
|
|
validation_state.live_min_clamp_offsets[i] = ~0;
|
|
|
|
+ validation_state.branch_targets =
|
|
+ kcalloc(BITS_TO_LONGS(validation_state.max_ip),
|
|
+ sizeof(unsigned long), GFP_KERNEL);
|
|
+ if (!validation_state.branch_targets)
|
|
+ goto fail;
|
|
+
|
|
validated_shader = kcalloc(1, sizeof(*validated_shader), GFP_KERNEL);
|
|
if (!validated_shader)
|
|
- return NULL;
|
|
+ goto fail;
|
|
+
|
|
+ if (!vc4_validate_branches(&validation_state))
|
|
+ goto fail;
|
|
|
|
for (ip = 0; ip < validation_state.max_ip; ip++) {
|
|
uint64_t inst = validation_state.shader[ip];
|
|
@@ -508,9 +615,12 @@ vc4_validate_shader(struct drm_gem_cma_o
|
|
(validated_shader->uniforms_size +
|
|
4 * validated_shader->num_texture_samples);
|
|
|
|
+ kfree(validation_state.branch_targets);
|
|
+
|
|
return validated_shader;
|
|
|
|
fail:
|
|
+ kfree(validation_state.branch_targets);
|
|
if (validated_shader) {
|
|
kfree(validated_shader->texture_samples);
|
|
kfree(validated_shader);
|