From da37f481a3f0b884c3ef6dc2a8d57beb85bc9978 Mon Sep 17 00:00:00 2001 From: Phil Elwell Date: Thu, 25 Jun 2015 08:47:09 +0100 Subject: [PATCH 092/171] bcm2835-sdhost: Further improve overclock back-off --- drivers/mmc/host/bcm2835-sdhost.c | 144 +++++++++++++++++++++----------------- 1 file changed, 78 insertions(+), 66 deletions(-) --- a/drivers/mmc/host/bcm2835-sdhost.c +++ b/drivers/mmc/host/bcm2835-sdhost.c @@ -161,8 +161,6 @@ struct bcm2835_host { unsigned int use_busy:1; /* Wait for busy interrupt */ - unsigned int reduce_overclock:1; /* ...at the next opportunity */ - unsigned int debug:1; /* Enable debug output */ u32 thread_isr; @@ -466,36 +464,25 @@ static void bcm2835_sdhost_dma_complete( spin_unlock_irqrestore(&host->lock, flags); } -static bool data_transfer_wait(struct bcm2835_host *host, const char *caller) +static bool data_transfer_wait(struct bcm2835_host *host) { unsigned long timeout = 1000000; - u32 hsts; while (timeout) { - hsts = bcm2835_sdhost_read(host, SDHSTS); - if (hsts & (SDHSTS_TRANSFER_ERROR_MASK | - SDHSTS_DATA_FLAG)) { - bcm2835_sdhost_write(host, SDHSTS_TRANSFER_ERROR_MASK, - SDHSTS); + u32 sdhsts = bcm2835_sdhost_read(host, SDHSTS); + if (sdhsts & SDHSTS_DATA_FLAG) { + bcm2835_sdhost_write(host, SDHSTS_DATA_FLAG, SDHSTS); break; } timeout--; } - - if (hsts & (SDHSTS_CRC16_ERROR | - SDHSTS_CRC7_ERROR | - SDHSTS_FIFO_ERROR)) { - pr_err("%s: data error in %s - HSTS %x\n", - mmc_hostname(host->mmc), caller, hsts); - host->data->error = -EILSEQ; - return false; - } else if ((timeout == 0) || - (hsts & (SDHSTS_CMD_TIME_OUT | - SDHSTS_REW_TIME_OUT))) { - pr_err("%s: timeout in %s - HSTS %x\n", - mmc_hostname(host->mmc), caller, hsts); - host->data->error = -ETIMEDOUT; - return false; + if (timeout == 0) { + pr_err("%s: Data %s timeout\n", + mmc_hostname(host->mmc), + (host->data->flags & MMC_DATA_READ) ? "read" : "write"); + bcm2835_sdhost_dumpregs(host); + host->data->error = -ETIMEDOUT; + return false; } return true; } @@ -523,7 +510,7 @@ static void bcm2835_sdhost_read_block_pi buf = (u32 *)host->sg_miter.addr; while (len) { - if (!data_transfer_wait(host, "read_block_pio")) + if (!data_transfer_wait(host)) break; *(buf++) = bcm2835_sdhost_read(host, SDDATA); @@ -562,7 +549,7 @@ static void bcm2835_sdhost_write_block_p buf = host->sg_miter.addr; while (len) { - if (!data_transfer_wait(host, "write_block_pio")) + if (!data_transfer_wait(host)) break; bcm2835_sdhost_write(host, *(buf++), SDDATA); @@ -581,13 +568,33 @@ static void bcm2835_sdhost_write_block_p static void bcm2835_sdhost_transfer_pio(struct bcm2835_host *host) { + u32 sdhsts; + bool is_read; BUG_ON(!host->data); - if (host->data->flags & MMC_DATA_READ) { + is_read = (host->data->flags & MMC_DATA_READ) != 0; + if (is_read) bcm2835_sdhost_read_block_pio(host); - } else { + else bcm2835_sdhost_write_block_pio(host); + sdhsts = bcm2835_sdhost_read(host, SDHSTS); + if (sdhsts & (SDHSTS_CRC16_ERROR | + SDHSTS_CRC7_ERROR | + SDHSTS_FIFO_ERROR)) { + pr_err("%s: %s transfer error - HSTS %x\n", + mmc_hostname(host->mmc), + is_read ? "read" : "write", + sdhsts); + host->data->error = -EILSEQ; + } else if ((sdhsts & (SDHSTS_CMD_TIME_OUT | + SDHSTS_REW_TIME_OUT))) { + pr_err("%s: %s timeout error - HSTS %x\n", + mmc_hostname(host->mmc), + is_read ? "read" : "write", + sdhsts); + host->data->error = -ETIMEDOUT; + } else if (!is_read && !host->data->error) { /* Start a timer in case a transfer error occurs because there is no error interrupt */ mod_timer(&host->pio_timer, jiffies + host->pio_timeout); @@ -701,8 +708,9 @@ static void bcm2835_sdhost_prepare_data( void bcm2835_sdhost_send_command(struct bcm2835_host *host, struct mmc_command *cmd) { - u32 sdcmd; + u32 sdcmd, sdhsts; unsigned long timeout; + int delay; WARN_ON(host->cmd); @@ -719,8 +727,8 @@ void bcm2835_sdhost_send_command(struct mmc_hostname(host->mmc), cmd->opcode, cmd->arg, cmd->flags); - /* Wait max 10 ms */ - timeout = 1000; + /* Wait max 100 ms */ + timeout = 10000; while (bcm2835_sdhost_read(host, SDCMD) & SDCMD_NEW_FLAG) { if (timeout == 0) { @@ -735,8 +743,9 @@ void bcm2835_sdhost_send_command(struct udelay(10); } - if ((1000-timeout)/100 > 1 && (1000-timeout)/100 > host->max_delay) { - host->max_delay = (1000-timeout)/100; + delay = (10000 - timeout)/100; + if (delay > host->max_delay) { + host->max_delay = delay; pr_warning("%s: controller hung for %d ms\n", mmc_hostname(host->mmc), host->max_delay); @@ -751,6 +760,11 @@ void bcm2835_sdhost_send_command(struct host->cmd = cmd; + /* Clear any error flags */ + sdhsts = bcm2835_sdhost_read(host, SDHSTS); + if (sdhsts & SDHSTS_ERROR_MASK) + bcm2835_sdhost_write(host, sdhsts, SDHSTS); + bcm2835_sdhost_prepare_data(host, cmd); bcm2835_sdhost_write(host, cmd->arg, SDARG); @@ -876,7 +890,7 @@ static void bcm2835_sdhost_transfer_comp static void bcm2835_sdhost_finish_command(struct bcm2835_host *host) { u32 sdcmd; - int timeout = 1000; + unsigned long timeout; #ifdef DEBUG struct timeval before, after; int timediff = 0; @@ -889,6 +903,8 @@ static void bcm2835_sdhost_finish_comman #ifdef DEBUG do_gettimeofday(&before); #endif + /* Wait max 100 ms */ + timeout = 10000; for (sdcmd = bcm2835_sdhost_read(host, SDCMD); (sdcmd & SDCMD_NEW_FLAG) && timeout; timeout--) { @@ -1049,9 +1065,9 @@ static void bcm2835_sdhost_pio_timeout(u spin_lock_irqsave(&host->lock, flags); if (host->data) { - u32 hsts = bcm2835_sdhost_read(host, SDHSTS); + u32 sdhsts = bcm2835_sdhost_read(host, SDHSTS); - if (hsts & SDHSTS_REW_TIME_OUT) { + if (sdhsts & SDHSTS_REW_TIME_OUT) { pr_err("%s: transfer timeout\n", mmc_hostname(host->mmc)); if (host->debug) @@ -1380,19 +1396,10 @@ void bcm2835_sdhost_set_clock(struct bcm if (host->debug) pr_info("%s: set_clock(%d)\n", mmc_hostname(host->mmc), clock); - if ((clock == 0) && host->reduce_overclock) { - /* This is a reset following data corruption - reduce any - overclock */ - host->reduce_overclock = 0; - if (host->overclock_50 > 50) { - pr_warn("%s: reducing overclock due to errors\n", - mmc_hostname(host->mmc)); - host->overclock_50--; - } - } - - if (host->overclock_50 && (clock == 50*MHZ)) + if ((host->overclock_50 > 50) && + (clock == 50*MHZ)) { clock = host->overclock_50 * MHZ + (MHZ - 1); + } /* The SDCDIV register has 11 bits, and holds (div - 2). But in data mode the max is 50MHz wihout a minimum, and only the @@ -1450,11 +1457,12 @@ void bcm2835_sdhost_set_clock(struct bcm host->overclock = clock; } } - else if ((clock == 50 * MHZ) && host->overclock) + else if (host->overclock) { - pr_warn("%s: cancelling overclock\n", - mmc_hostname(host->mmc)); host->overclock = 0; + if (clock == 50 * MHZ) + pr_warn("%s: cancelling overclock\n", + mmc_hostname(host->mmc)); } host->cdiv = div; @@ -1492,6 +1500,14 @@ static void bcm2835_sdhost_request(struc cmd->opcode, cmd->arg, cmd->flags); } + /* Reset the error statuses in case this is a retry */ + if (mrq->cmd) + mrq->cmd->error = 0; + if (mrq->data) + mrq->data->error = 0; + if (mrq->stop) + mrq->stop->error = 0; + if (mrq->data && !is_power_of_2(mrq->data->blksz)) { pr_err("%s: unsupported block size (%d bytes)\n", mmc_hostname(mmc), mrq->data->blksz); @@ -1613,21 +1629,16 @@ static void bcm2835_sdhost_tasklet_finis /* Drop the overclock after any data corruption, or after any error overclocked */ - if (mrq->data && (mrq->data->error == -EILSEQ)) - host->reduce_overclock = 1; - else if (host->overclock) { - /* Convert timeout errors while overclocked to data errors, - because the system recovers better. */ - if (mrq->cmd && mrq->cmd->error) { - host->reduce_overclock = 1; - if (mrq->cmd->error == -ETIMEDOUT) - mrq->cmd->error = -EILSEQ; - } - - if (mrq->data && mrq->data->error) { - host->reduce_overclock = 1; - if (mrq->data->error == -ETIMEDOUT) - mrq->data->error = -EILSEQ; + if (host->overclock) { + if ((mrq->cmd && mrq->cmd->error) || + (mrq->data && mrq->data->error) || + (mrq->stop && mrq->stop->error)) { + host->overclock_50--; + pr_warn("%s: reducing overclock due to errors\n", + mmc_hostname(host->mmc)); + bcm2835_sdhost_set_clock(host,50*MHZ); + mrq->cmd->error = -EILSEQ; + mrq->cmd->retries = 1; } } @@ -1769,6 +1780,7 @@ static int bcm2835_sdhost_probe(struct p host = mmc_priv(mmc); host->mmc = mmc; host->pio_timeout = msecs_to_jiffies(500); + host->max_delay = 1; /* Warn if over 1ms */ spin_lock_init(&host->lock); iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0);