The original intention of the mmc load_image() function was to try multiple boot modes before failing. This is evident by the lack of break statements in the switch, and the following line in the default case: puts("spl: mmc: no boot mode left to try\n");
This implementation is problematic because: - The availability of alternative boot modes is very arbitrary since it depends on the specific order of the switch cases. If your boot mode happens to be the first case, then you'll have a bunch of other boot modes as alternatives. If it happens to be the last case, then you have none. - Opting in/out is tied to config options, so the only way for you to prevent an alternative boot mode from being attempted is to give up on the feature completely. - This implementation makes the code more complicated and difficult to understand.
Address these issues by inserting a break statements between the cases to make the function try only one boot mode.
Signed-off-by: Nikita Kiryanov nikita@compulab.co.il Cc: Igor Grinberg grinberg@compulab.co.il Cc: Paul Kocialkowski contact@paulk.fr Cc: Pantelis Antoniou panto@antoniou-consulting.com Cc: Tom Rini trini@konsulko.com Cc: Simon Glass sjg@chromium.org Reviewed-by: Simon Glass sjg@chromium.org Reviewed-by: Tom Rini trini@konsulko.com --- Changes in V4: - No changes.
Changes in V3: - No changes.
Changes in V2: - Removed hang() in default cases, moved default case into ifdef LIBCOMMON.
common/spl/spl_mmc.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-)
diff --git a/common/spl/spl_mmc.c b/common/spl/spl_mmc.c index ce58c58..6011f77 100644 --- a/common/spl/spl_mmc.c +++ b/common/spl/spl_mmc.c @@ -164,6 +164,7 @@ void spl_mmc_load_image(void) if (!err) return; #endif + break; case MMCSD_MODE_FS: debug("spl: mmc boot mode: fs\n");
@@ -203,6 +204,7 @@ void spl_mmc_load_image(void) #endif #endif #endif + break; #ifdef CONFIG_SUPPORT_EMMC_BOOT case MMCSD_MODE_EMMCBOOT: /* @@ -240,15 +242,14 @@ void spl_mmc_load_image(void) if (!err) return; #endif + break; #endif case MMCSD_MODE_UNDEFINED: - default: #ifdef CONFIG_SPL_LIBCOMMON_SUPPORT - if (err) - puts("spl: mmc: no boot mode left to try\n"); - else - puts("spl: mmc: wrong boot mode\n"); + default: + puts("spl: mmc: wrong boot mode\n"); #endif - hang(); } + + hang(); }