| Message ID | 1304596282-4095-14-git-send-email-adrian.hunter@nokia.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Thu, May 5, 2011 at 2:51 PM, Adrian Hunter <adrian.hunter@nokia.com> wrote: > From: Andy Shevchenko <ext-andriy.shevchenko@nokia.com> > > There are two pieces of code which similar, but not the same. Each of them > contains a bug. > > The SYSCTL register should be read before write in the > omap_hsmmc_context_restore() to remain the state of the reserved bits. > > Before set the clock divisor and DTO bits the value from the SYSCTL register > should be masked properly. We were lucky to have no problems with DTO bits. So, > make sure we have clear DTO bits properly in the omap_hsmmc_set_ios(). > > Additionally get rid of msleep(1). The actual time rare higher than 30us on > OMAP 3630. > > The result pieces of code are split to omap_hsmmc_set_clock() function. > > Signed-off-by: Andy Shevchenko <ext-andriy.shevchenko@nokia.com> > Signed-off-by: Adrian Hunter <adrian.hunter@nokia.com> > --- > drivers/mmc/host/omap_hsmmc.c | 59 +++++++++++++++++++--------------------- > 1 files changed, 28 insertions(+), 31 deletions(-) > > diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c > index ae6d204..3c76911 100644 > --- a/drivers/mmc/host/omap_hsmmc.c > +++ b/drivers/mmc/host/omap_hsmmc.c > @@ -619,6 +619,32 @@ static u16 calc_divisor(struct mmc_ios *ios) > return dsor; > } > > +static void omap_hsmmc_set_clock(struct omap_hsmmc_host *host) > +{ > + struct mmc_ios *ios = &host->mmc->ios; > + unsigned long regval; > + unsigned long timeout; > + > + dev_dbg(mmc_dev(host->mmc), "Set clock to %uHz\n", ios->clock); > + > + omap_hsmmc_stop_clock(host); > + > + regval = OMAP_HSMMC_READ(host->base, SYSCTL); > + regval = regval & ~(CLKD_MASK | DTO_MASK); > + regval = regval | (calc_divisor(ios) << 6) | (DTO << 16); > + OMAP_HSMMC_WRITE(host->base, SYSCTL, regval); > + OMAP_HSMMC_WRITE(host->base, SYSCTL, > + OMAP_HSMMC_READ(host->base, SYSCTL) | ICE); > + > + /* Wait till the ICS bit is set */ > + timeout = jiffies + msecs_to_jiffies(MMC_TIMEOUT_MS); > + while ((OMAP_HSMMC_READ(host->base, SYSCTL) & ICS) != ICS > + && time_before(jiffies, timeout)) > + ; Since you are busywaiting now, cpu_relax() is advisable I guess. -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c index ae6d204..3c76911 100644 --- a/drivers/mmc/host/omap_hsmmc.c +++ b/drivers/mmc/host/omap_hsmmc.c @@ -619,6 +619,32 @@ static u16 calc_divisor(struct mmc_ios *ios) return dsor; } +static void omap_hsmmc_set_clock(struct omap_hsmmc_host *host) +{ + struct mmc_ios *ios = &host->mmc->ios; + unsigned long regval; + unsigned long timeout; + + dev_dbg(mmc_dev(host->mmc), "Set clock to %uHz\n", ios->clock); + + omap_hsmmc_stop_clock(host); + + regval = OMAP_HSMMC_READ(host->base, SYSCTL); + regval = regval & ~(CLKD_MASK | DTO_MASK); + regval = regval | (calc_divisor(ios) << 6) | (DTO << 16); + OMAP_HSMMC_WRITE(host->base, SYSCTL, regval); + OMAP_HSMMC_WRITE(host->base, SYSCTL, + OMAP_HSMMC_READ(host->base, SYSCTL) | ICE); + + /* Wait till the ICS bit is set */ + timeout = jiffies + msecs_to_jiffies(MMC_TIMEOUT_MS); + while ((OMAP_HSMMC_READ(host->base, SYSCTL) & ICS) != ICS + && time_before(jiffies, timeout)) + ; + + omap_hsmmc_start_clock(host); +} + #ifdef CONFIG_PM /* @@ -709,19 +735,7 @@ static int omap_hsmmc_context_restore(struct omap_hsmmc_host *host) break; } - omap_hsmmc_stop_clock(host); - - OMAP_HSMMC_WRITE(host->base, SYSCTL, - (calc_divisor(ios) << 6) | (DTO << 16)); - OMAP_HSMMC_WRITE(host->base, SYSCTL, - OMAP_HSMMC_READ(host->base, SYSCTL) | ICE); - - timeout = jiffies + msecs_to_jiffies(MMC_TIMEOUT_MS); - while ((OMAP_HSMMC_READ(host->base, SYSCTL) & ICS) != ICS - && time_before(jiffies, timeout)) - ; - - omap_hsmmc_start_clock(host); + omap_hsmmc_set_clock(host); con = OMAP_HSMMC_READ(host->base, CON); if (ios->bus_mode == MMC_BUSMODE_OPENDRAIN) @@ -1622,8 +1636,6 @@ static void omap_hsmmc_request(struct mmc_host *mmc, struct mmc_request *req) static void omap_hsmmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) { struct omap_hsmmc_host *host = mmc_priv(mmc); - unsigned long regval; - unsigned long timeout; u32 con; int do_send_init_stream = 0; @@ -1685,22 +1697,7 @@ static void omap_hsmmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) } } - omap_hsmmc_stop_clock(host); - - regval = OMAP_HSMMC_READ(host->base, SYSCTL); - regval = regval & ~(CLKD_MASK); - regval = regval | (calc_divisor(ios) << 6) | (DTO << 16); - OMAP_HSMMC_WRITE(host->base, SYSCTL, regval); - OMAP_HSMMC_WRITE(host->base, SYSCTL, - OMAP_HSMMC_READ(host->base, SYSCTL) | ICE); - - /* Wait till the ICS bit is set */ - timeout = jiffies + msecs_to_jiffies(MMC_TIMEOUT_MS); - while ((OMAP_HSMMC_READ(host->base, SYSCTL) & ICS) != ICS - && time_before(jiffies, timeout)) - msleep(1); - - omap_hsmmc_start_clock(host); + omap_hsmmc_set_clock(host); if (do_send_init_stream) send_init_stream(host);