diff --git a/src/amd/common/ac_nir.h b/src/amd/common/ac_nir.h
index 3ea8e4d9261..f646fa2ced6 100644
--- a/src/amd/common/ac_nir.h
+++ b/src/amd/common/ac_nir.h
@@ -293,7 +293,7 @@ typedef struct {
    bool force_linear_sample_interp;
    bool force_persp_center_interp;
    bool force_linear_center_interp;
-   unsigned samplemask_log_ps_iter;
+   unsigned ps_iter_samples;
 
    /* OpenGL only */
    bool clamp_color;
diff --git a/src/amd/common/ac_nir_lower_ps.c b/src/amd/common/ac_nir_lower_ps.c
index 90e99b22c27..771e1064a23 100644
--- a/src/amd/common/ac_nir_lower_ps.c
+++ b/src/amd/common/ac_nir_lower_ps.c
@@ -248,16 +248,7 @@ lower_ps_load_sample_mask_in(nir_builder *b, nir_intrinsic_instr *intrin, lower_
 
    b->cursor = nir_before_instr(&intrin->instr);
 
-   /* The bit pattern matches that used by fixed function fragment
-    * processing.
-    */
-   static const uint16_t ps_iter_masks[] = {
-      0xffff, /* not used */
-      0x5555, 0x1111, 0x0101, 0x0001,
-   };
-   assert(s->options->samplemask_log_ps_iter < ARRAY_SIZE(ps_iter_masks));
-   uint32_t ps_iter_mask = ps_iter_masks[s->options->samplemask_log_ps_iter];
-
+   uint32_t ps_iter_mask = ac_get_ps_iter_mask(s->options->ps_iter_samples);
    nir_ssa_def *sampleid = nir_load_sample_id(b);
    nir_ssa_def *submask = nir_ishl(b, nir_imm_int(b, ps_iter_mask), sampleid);
 
@@ -290,7 +281,7 @@ lower_ps_intrinsic(nir_builder *b, nir_instr *instr, void *state)
          return lower_ps_load_barycentric(b, intrin, s);
       break;
    case nir_intrinsic_load_sample_mask_in:
-      if (s->options->samplemask_log_ps_iter)
+      if (s->options->ps_iter_samples > 1)
          return lower_ps_load_sample_mask_in(b, intrin, s);
       break;
    default:
diff --git a/src/amd/common/ac_shader_util.c b/src/amd/common/ac_shader_util.c
index e5d4b8734bf..fbdb0d0e6d4 100644
--- a/src/amd/common/ac_shader_util.c
+++ b/src/amd/common/ac_shader_util.c
@@ -678,6 +678,22 @@ unsigned ac_get_fs_input_vgpr_cnt(const struct ac_shader_config *config,
    return num_input_vgprs;
 }
 
+uint16_t ac_get_ps_iter_mask(unsigned ps_iter_samples)
+{
+   /* The bit pattern matches that used by fixed function fragment
+    * processing.
+    */
+   switch (ps_iter_samples) {
+   case 1: return 0xffff;
+   case 2: return 0x5555;
+   case 4: return 0x1111;
+   case 8: return 0x0101;
+   case 16: return 0x0001;
+   default:
+      unreachable("invalid sample count");
+   }
+}
+
 void ac_choose_spi_color_formats(unsigned format, unsigned swap, unsigned ntype,
                                  bool is_depth, bool use_rbplus,
                                  struct ac_spi_color_formats *formats)
diff --git a/src/amd/common/ac_shader_util.h b/src/amd/common/ac_shader_util.h
index b06ecd73c2b..a11debbd8f9 100644
--- a/src/amd/common/ac_shader_util.h
+++ b/src/amd/common/ac_shader_util.h
@@ -173,6 +173,8 @@ unsigned ac_get_fs_input_vgpr_cnt(const struct ac_shader_config *config,
                                   signed char *face_vgpr_index, signed char *ancillary_vgpr_index,
                                   signed char *sample_coverage_vgpr_index_ptr);
 
+uint16_t ac_get_ps_iter_mask(unsigned ps_iter_samples);
+
 void ac_choose_spi_color_formats(unsigned format, unsigned swap, unsigned ntype,
                                  bool is_depth, bool use_rbplus,
                                  struct ac_spi_color_formats *formats);
diff --git a/src/gallium/drivers/radeonsi/si_shader.c b/src/gallium/drivers/radeonsi/si_shader.c
index f03f3413bb4..a48aca5bd77 100644
--- a/src/gallium/drivers/radeonsi/si_shader.c
+++ b/src/gallium/drivers/radeonsi/si_shader.c
@@ -2242,7 +2242,7 @@ struct nir_shader *si_get_nir_shader(struct si_shader *shader,
          .force_linear_sample_interp = key->ps.part.prolog.force_linear_sample_interp,
          .force_persp_center_interp = key->ps.part.prolog.force_persp_center_interp,
          .force_linear_center_interp = key->ps.part.prolog.force_linear_center_interp,
-         .samplemask_log_ps_iter = key->ps.part.prolog.samplemask_log_ps_iter,
+         .ps_iter_samples = 1 << key->ps.part.prolog.samplemask_log_ps_iter,
       };
 
       NIR_PASS_V(nir, ac_nir_lower_ps, &options);
diff --git a/src/gallium/drivers/radeonsi/si_shader_llvm_ps.c b/src/gallium/drivers/radeonsi/si_shader_llvm_ps.c
index 30334bdab26..6bbe7c248df 100644
--- a/src/gallium/drivers/radeonsi/si_shader_llvm_ps.c
+++ b/src/gallium/drivers/radeonsi/si_shader_llvm_ps.c
@@ -687,15 +687,8 @@ void si_llvm_build_ps_prolog(struct si_shader_context *ctx, union si_shader_part
     * entire pixel/fragment, so mask bits out based on the sample ID.
     */
    if (key->ps_prolog.states.samplemask_log_ps_iter) {
-      /* The bit pattern matches that used by fixed function fragment
-       * processing. */
-      static const uint16_t ps_iter_masks[] = {
-         0xffff, /* not used */
-         0x5555, 0x1111, 0x0101, 0x0001,
-      };
-      assert(key->ps_prolog.states.samplemask_log_ps_iter < ARRAY_SIZE(ps_iter_masks));
-
-      uint32_t ps_iter_mask = ps_iter_masks[key->ps_prolog.states.samplemask_log_ps_iter];
+      uint32_t ps_iter_mask =
+         ac_get_ps_iter_mask(1 << key->ps_prolog.states.samplemask_log_ps_iter);
       LLVMValueRef sampleid = si_unpack_param(ctx, ancillary, 8, 4);
       LLVMValueRef samplemask = ac_get_arg(&ctx->ac, param_sample_mask);