Hi, Thanks for comments. On 02/10/2015 03:54 PM, Alim Akhtar wrote: > Hi Andrzej, > > On Tue, Feb 10, 2015 at 7:59 PM, Andrzej Hajda <a.hajda@xxxxxxxxxxx> wrote: >> According to specs for version 250A, status register should be >> tested before clock update. Otherwise in case MMC card is missing >> mci_send_cmd timeouts and subsequent CTYPE registry write causes system hang. >> This behavior has been observed on Exynos5422/Odroid-XU3. >> > A similar patch was posted recently[1], did you check that? > [1] http://www.spinics.net/lists/linux-doc/msg28092.html No, thanks for pointing it. I will look at it closer. > >> Signed-off-by: Andrzej Hajda <a.hajda@xxxxxxxxxxx> >> --- >> Hi, >> >> This version corrects usleep to usleep_range function call. >> >> Regards >> Andrzej >> --- >> drivers/mmc/host/dw_mmc.c | 26 ++++++++++++++++++++++++-- >> drivers/mmc/host/dw_mmc.h | 1 + >> 2 files changed, 25 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c >> index 67c0451..6619c8a 100644 >> --- a/drivers/mmc/host/dw_mmc.c >> +++ b/drivers/mmc/host/dw_mmc.c >> @@ -878,6 +878,25 @@ static void mci_send_cmd(struct dw_mci_slot *slot, u32 cmd, u32 arg) >> cmd, arg, cmd_status); >> } >> >> +static bool dw_mci_wait_busy(struct dw_mci *host) >> +{ >> + unsigned long timeout; >> + >> + if (host->verid < DW_MMC_250A) >> + return true; >> + > I wonder this might be true for 240A as well. Odroid-U3 board with Exynos4412 and MMC 240A does not have this problem. On the other side busy check does not hurt it anyway. Relevant part of dmesg for Exynos4412/mmc_240a: ... [ 2.193967] mmc1: req done (CMD55): -110: 00000000 00000000 00000000 00000000 [ 2.194000] mmc1: clock 400000Hz busmode 1 powermode 2 cs 0 Vdd 7 width 0 timing 0 [ 2.194010] mmc1: starting CMD1 arg 00000000 flags 000000e1 [ 2.194821] mmc1: req done (CMD1): -110: 00000000 00000000 00000000 00000000 [ 2.194854] mmc1: clock 0Hz busmode 2 powermode 0 cs 0 Vdd 0 width 0 timing 0 [ 3.195404] mmc1: clock 0Hz busmode 2 powermode 1 cs 0 Vdd 7 width 0 timing 0 ... and for Exynos5422/mmc_250a: [ 3.530672] mmc0: req done (CMD55): -5: 00000000 00000000 00000000 00000000 [ 3.530707] mmc0: clock 400000Hz busmode 1 powermode 2 cs 0 Vdd 21 width 0 timing 0 [ 3.530716] mmc0: starting CMD1 arg 00000000 flags 000000e1 [ 3.531004] mmc0: req done (CMD1): -5: 00000000 00000000 00000000 00000000 [ 3.531039] mmc0: clock 0Hz busmode 2 powermode 0 cs 0 Vdd 0 width 0 timing 0 [ 4.031304] mmc_host mmc0: Busy timeout (cmd 0x202000 arg 0x0) [ 5.031323] mmc0: clock 0Hz busmode 2 powermode 1 cs 0 Vdd 21 width 0 timing 0 [ 5.536385] mmc_host mmc0: Busy timeout (cmd 0x202000 arg 0x0) > >> + timeout = jiffies + msecs_to_jiffies(500); >> + while (time_before(jiffies, timeout)) { >> + if (!(mci_readl(host, STATUS) & SDMMC_STATUS_BUSY)) >> + return true; >> + >> + usleep_range(1000, 2000); >> + } >> + dev_err(host->dev, "Busy timeout\n"); > Probably you need a controller reset here to bring back controller is > original state. OK. Regards Andrzej >> + >> + return false; >> +} >> + >> static void dw_mci_setup_bus(struct dw_mci_slot *slot, bool force_clkinit) >> { >> struct dw_mci *host = slot->host; >> @@ -891,8 +910,11 @@ static void dw_mci_setup_bus(struct dw_mci_slot *slot, bool force_clkinit) >> sdmmc_cmd_bits |= SDMMC_CMD_VOLT_SWITCH; >> >> if (!clock) { >> - mci_writel(host, CLKENA, 0); >> - mci_send_cmd(slot, sdmmc_cmd_bits, 0); >> + if (dw_mci_wait_busy(host)) { >> + mci_writel(host, CLKENA, 0); >> + mci_send_cmd(slot, sdmmc_cmd_bits, 0); >> + } else >> + return; >> } else if (clock != host->current_speed || force_clkinit) { >> div = host->bus_hz / clock; >> if (host->bus_hz % clock && host->bus_hz > clock) >> diff --git a/drivers/mmc/host/dw_mmc.h b/drivers/mmc/host/dw_mmc.h >> index 0d0f7a27..ea6d4d1 100644 >> --- a/drivers/mmc/host/dw_mmc.h >> +++ b/drivers/mmc/host/dw_mmc.h >> @@ -15,6 +15,7 @@ >> #define _DW_MMC_H_ >> >> #define DW_MMC_240A 0x240a >> +#define DW_MMC_250A 0x250a >> >> #define SDMMC_CTRL 0x000 >> #define SDMMC_PWREN 0x004 >> -- >> 1.9.1 >> >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-mmc" in >> the body of a message to majordomo@xxxxxxxxxxxxxxx >> More majordomo info at http://vger.kernel.org/majordomo-info.html > > -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
