[Qemu-devel] [PATCH 3/4] aspeed/smc: handle dummies only in fast read mode

Cédric Le Goater posted 4 patches 171 weeks ago

[Qemu-devel] [PATCH 3/4] aspeed/smc: handle dummies only in fast read mode

Posted by Cédric Le Goater 171 weeks ago
HW works fine in normal read mode with dummy bytes being set. So let's
check this case to not transfer bytes.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
---
 hw/ssi/aspeed_smc.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/hw/ssi/aspeed_smc.c b/hw/ssi/aspeed_smc.c
index 087b29e8da10..70177078a8f2 100644
--- a/hw/ssi/aspeed_smc.c
+++ b/hw/ssi/aspeed_smc.c
@@ -536,10 +536,13 @@ static uint64_t aspeed_smc_flash_read(void *opaque, hwaddr addr, unsigned size)
         /*
          * Use fake transfers to model dummy bytes. The value should
          * be configured to some non-zero value in fast read mode and
-         * zero in read mode.
+         * zero in read mode. But, as the HW allows inconsistent
+         * settings, let's check for fast read mode.
          */
-        for (i = 0; i < aspeed_smc_flash_dummies(fl); i++) {
-            ssi_transfer(fl->controller->spi, 0xFF);
+        if (aspeed_smc_flash_mode(fl) == CTRL_FREADMODE) {
+            for (i = 0; i < aspeed_smc_flash_dummies(fl); i++) {
+                ssi_transfer(fl->controller->spi, 0xFF);
+            }
         }
 
         for (i = 0; i < size; i++) {
-- 
2.7.4