diff --git a/src/amd/common/ac_descriptors.h b/src/amd/common/ac_descriptors.h
index 99cafa8a110..f938edc593c 100644
--- a/src/amd/common/ac_descriptors.h
+++ b/src/amd/common/ac_descriptors.h
@@ -17,6 +17,7 @@
 extern "C" {
 #endif
 
+#define DUPL_16BITS_IN_DWORD(x) (((x) << 16) | (x))
 #define DUPL_8BITS_IN_DWORD(x) (((x) << 24) | ((x) << 16) | ((x) << 8) | (x))
 #define DUPL_4BITS_IN_DWORD(x) DUPL_8BITS_IN_DWORD((x) | ((x) << 4))
 
@@ -67,6 +68,45 @@ enum {
    CMASK_8xMSAA_FMASK_UNCOMPRESSED_COLOR_EXPANDED  = CMASK_MSAA_CODE(3, 3),
 };
 
+enum {
+   /* Don't ever use this. Clear CMASK instead. */
+   FMASK_CLEAR_0 = 0,
+
+   /* These can be used only if FMASK is uncompressed in CMASK.
+    *
+    * Uncompressed doesn't mean expanded.
+    * - FMASK compression only affects bandwidth, not stored values. The compression is done by CMASK.
+    * - Expanded FMASK means that specific values are stored in it such that FMASK has no effect.
+    *   FMASK expansion is a layout transition only required before MSAA image stores.
+    * - CB_FMASK_DECOMPRESS is a layout transition required before any shader access, and does:
+    *     1. FMASK decompression: Eliminating CMASK compression.
+    *     2. CMASK fast color clear elimination: Writing the clear value in CB_COLORi_CLEAR_WORDj
+    *        registers to cleared areas of the color image.
+    *     ! It doesn't do FMASK expansion, which must be done by a compute shader.
+    * - GFX8-10.3: To avoid CB_FMASK_DECOMPRESS before shader access (except MSAA image stores):
+    *    - Use FMASK with TC-compatible CMASK. (enabled by FMASK_COMPRESS_1FRAG_ONLY)
+    *    - Use DCC for fast MSAA color clears instead of CMASK.
+    */
+   FMASK_2xMSAA_EXPANDED = DUPL_8BITS_IN_DWORD(0x02),
+   FMASK_4xMSAA_EXPANDED = DUPL_8BITS_IN_DWORD(0xE4),
+   FMASK_8xMSAA_EXPANDED = 0x76543210,
+
+   FMASK_EQAA_2S_1F_EXPANDED = FMASK_2xMSAA_EXPANDED,
+   FMASK_EQAA_4S_1F_EXPANDED = DUPL_8BITS_IN_DWORD(0x0E),
+   FMASK_EQAA_8S_1F_EXPANDED = DUPL_8BITS_IN_DWORD(0xFE),
+   FMASK_EQAA_16S_1F_EXPANDED = DUPL_16BITS_IN_DWORD(0xFFFE),
+
+   FMASK_EQAA_4S_2F_EXPANDED = DUPL_8BITS_IN_DWORD(0xA4),
+   FMASK_EQAA_8S_2F_EXPANDED = DUPL_16BITS_IN_DWORD(0xAAA4),
+   FMASK_EQAA_16S_2F_EXPANDED = 0xAAAAAAA4,
+
+   FMASK_EQAA_8S_4F_EXPANDED = 0x44443210,
+   FMASK_EQAA_16S_4F_EXPANDED = 0x4444444444443210ull, /* 8-byte clear value */
+
+   /* Enums don't allow such large numbers. */
+   #define FMASK_EQAA_16S_8F_EXPANDED 0x8888888876543210ull /* 8-byte clear value */
+};
+
 typedef union {
    /* Z only */
    struct {
diff --git a/src/amd/vulkan/radv_cmd_buffer.c b/src/amd/vulkan/radv_cmd_buffer.c
index d65491d1e55..b8bcdede794 100644
--- a/src/amd/vulkan/radv_cmd_buffer.c
+++ b/src/amd/vulkan/radv_cmd_buffer.c
@@ -14298,7 +14298,12 @@ radv_init_cmask(struct radv_cmd_buffer *cmd_buffer, struct radv_image *image, co
 uint32_t
 radv_init_fmask(struct radv_cmd_buffer *cmd_buffer, struct radv_image *image, const VkImageSubresourceRange *range)
 {
-   static const uint32_t fmask_clear_values[4] = {0x00000000, 0x02020202, 0xE4E4E4E4, 0x76543210};
+   static const uint32_t fmask_clear_values[4] = {
+      0, /* unused */
+      FMASK_2xMSAA_EXPANDED,
+      FMASK_4xMSAA_EXPANDED,
+      FMASK_8xMSAA_EXPANDED,
+   };
    uint32_t log2_samples = util_logbase2(image->vk.samples);
    uint32_t value = fmask_clear_values[log2_samples];
    struct radv_barrier_data barrier = {0};
diff --git a/src/gallium/drivers/radeonsi/si_compute_blit.c b/src/gallium/drivers/radeonsi/si_compute_blit.c
index d80df6404df..26b071ed1e7 100644
--- a/src/gallium/drivers/radeonsi/si_compute_blit.c
+++ b/src/gallium/drivers/radeonsi/si_compute_blit.c
@@ -481,14 +481,26 @@ void si_compute_expand_fmask(struct pipe_context *ctx, struct pipe_resource *tex
    pipe_resource_reference(&saved_image.resource, NULL);
 
    /* Array of fully expanded FMASK values, arranged by [log2(fragments)][log2(samples)-1]. */
-#define INVALID 0 /* never used */
-   static const uint64_t fmask_expand_values[][4] = {
-      /* samples */
-      /* 2 (8 bpp) 4 (8 bpp)   8 (8-32bpp) 16 (16-64bpp)      fragments */
-      {0x02020202, 0x0E0E0E0E, 0xFEFEFEFE, 0xFFFEFFFE},      /* 1 */
-      {0x02020202, 0xA4A4A4A4, 0xAAA4AAA4, 0xAAAAAAA4},      /* 2 */
-      {INVALID, 0xE4E4E4E4, 0x44443210, 0x4444444444443210}, /* 4 */
-      {INVALID, INVALID, 0x76543210, 0x8888888876543210},    /* 8 */
+   static const uint64_t fmask_expand_values[4][4] = {
+      {FMASK_EQAA_2S_1F_EXPANDED,
+       FMASK_EQAA_4S_1F_EXPANDED,
+       FMASK_EQAA_8S_1F_EXPANDED,
+       FMASK_EQAA_16S_1F_EXPANDED},
+
+      {FMASK_2xMSAA_EXPANDED,
+       FMASK_EQAA_4S_2F_EXPANDED,
+       FMASK_EQAA_8S_2F_EXPANDED,
+       FMASK_EQAA_16S_2F_EXPANDED},
+
+      {0,  /* unused */
+       FMASK_4xMSAA_EXPANDED,
+       FMASK_EQAA_8S_4F_EXPANDED,
+       FMASK_EQAA_16S_4F_EXPANDED},
+
+      {0,  /* unused */
+       0,  /* unused */
+       FMASK_8xMSAA_EXPANDED,
+       FMASK_EQAA_16S_8F_EXPANDED},
    };
 
    /* Clear FMASK to identity. */