mmc: dw_mmc: Fix the DTO/CTO timeout overflow calculation for 32-bit systems
authorEvgeniy Didin <Evgeniy.Didin@synopsys.com>
Wed, 28 Feb 2018 11:53:18 +0000 (14:53 +0300)
committerUlf Hansson <ulf.hansson@linaro.org>
Mon, 5 Mar 2018 08:36:17 +0000 (09:36 +0100)
The commit 9d9491a7da2a ("mmc: dw_mmc: Fix the DTO timeout calculation")
and commit 4c2357f57dd5 ("mmc: dw_mmc: Fix the CTO timeout calculation")
made changes, which cause multiply overflow for 32-bit systems. The broken
timeout calculations leads to unexpected ETIMEDOUT errors and causes
stacktrace splat (such as below) during normal data exchange with SD-card.

| Running :  4M-check-reassembly-tcp-cmykw2-rotatew2.out -v0 -w1
| -  Info: Finished target initialization.
| mmcblk0: error -110 transferring data, sector 320544, nr 2048, cmd
| response 0x900, card status 0x0

DIV_ROUND_UP_ULL helps to escape usage of __udivdi3() from libgcc and so
code gets compiled on all 32-bit platforms as opposed to usage of
DIV_ROUND_UP when we may only compile stuff on a very few arches.

Lets cast this multiply to u64 type to prevent the overflow.

Fixes: 9d9491a7da2a ("mmc: dw_mmc: Fix the DTO timeout calculation")
Fixes: 4c2357f57dd5 ("mmc: dw_mmc: Fix the CTO timeout calculation")
Tested-by: Vineet Gupta <Vineet.Gupta1@synopsys.com>
Reported-by: Vineet Gupta <Vineet.Gupta1@synopsys.com> # ARC STAR 9001306872 HSDK, sdio: board crashes when copying big files
Signed-off-by: Evgeniy Didin <Evgeniy.Didin@synopsys.com>
Cc: <stable@vger.kernel.org> # 4.14
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com>
Reviewed-by: Jisheng Zhang <Jisheng.Zhang@synaptics.com>
Acked-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
drivers/mmc/host/dw_mmc.c

index d9b4ace..5455505 100644 (file)
@@ -413,7 +413,9 @@ static inline void dw_mci_set_cto(struct dw_mci *host)
        cto_div = (mci_readl(host, CLKDIV) & 0xff) * 2;
        if (cto_div == 0)
                cto_div = 1;
-       cto_ms = DIV_ROUND_UP(MSEC_PER_SEC * cto_clks * cto_div, host->bus_hz);
+
+       cto_ms = DIV_ROUND_UP_ULL((u64)MSEC_PER_SEC * cto_clks * cto_div,
+                                 host->bus_hz);
 
        /* add a bit spare time */
        cto_ms += 10;
@@ -1948,8 +1950,9 @@ static void dw_mci_set_drto(struct dw_mci *host)
        drto_div = (mci_readl(host, CLKDIV) & 0xff) * 2;
        if (drto_div == 0)
                drto_div = 1;
-       drto_ms = DIV_ROUND_UP(MSEC_PER_SEC * drto_clks * drto_div,
-                              host->bus_hz);
+
+       drto_ms = DIV_ROUND_UP_ULL((u64)MSEC_PER_SEC * drto_clks * drto_div,
+                                  host->bus_hz);
 
        /* add a bit spare time */
        drto_ms += 10;