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mmc: sdhci: Factor out tuning helper functions

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Factor out some functions to tidy up the code in sdhci_execute_tuning.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This commit is contained in:
Adrian Hunter 2016-12-02 15:59:23 +02:00 committed by Ulf Hansson
parent d0c3ab5910
commit da4bc4f285
1 changed files with 124 additions and 92 deletions
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216
drivers/mmc/host/sdhci.c
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@ -1952,6 +1952,122 @@ static int sdhci_prepare_hs400_tuning(struct mmc_host *mmc, struct mmc_ios *ios)
return 0;
}
static void sdhci_start_tuning(struct sdhci_host *host)
{
u16 ctrl;
ctrl = sdhci_readw(host, SDHCI_HOST_CONTROL2);
ctrl |= SDHCI_CTRL_EXEC_TUNING;
if (host->quirks2 & SDHCI_QUIRK2_TUNING_WORK_AROUND)
ctrl |= SDHCI_CTRL_TUNED_CLK;
sdhci_writew(host, ctrl, SDHCI_HOST_CONTROL2);
/*
* As per the Host Controller spec v3.00, tuning command
* generates Buffer Read Ready interrupt, so enable that.
*
* Note: The spec clearly says that when tuning sequence
* is being performed, the controller does not generate
* interrupts other than Buffer Read Ready interrupt. But
* to make sure we don't hit a controller bug, we _only_
* enable Buffer Read Ready interrupt here.
*/
sdhci_writel(host, SDHCI_INT_DATA_AVAIL, SDHCI_INT_ENABLE);
sdhci_writel(host, SDHCI_INT_DATA_AVAIL, SDHCI_SIGNAL_ENABLE);
}
static void sdhci_end_tuning(struct sdhci_host *host)
{
sdhci_writel(host, host->ier, SDHCI_INT_ENABLE);
sdhci_writel(host, host->ier, SDHCI_SIGNAL_ENABLE);
}
static void sdhci_reset_tuning(struct sdhci_host *host)
{
u16 ctrl;
ctrl = sdhci_readw(host, SDHCI_HOST_CONTROL2);
ctrl &= ~SDHCI_CTRL_TUNED_CLK;
ctrl &= ~SDHCI_CTRL_EXEC_TUNING;
sdhci_writew(host, ctrl, SDHCI_HOST_CONTROL2);
}
static void sdhci_abort_tuning(struct sdhci_host *host, u32 opcode,
unsigned long flags)
{
sdhci_reset_tuning(host);
sdhci_do_reset(host, SDHCI_RESET_CMD);
sdhci_do_reset(host, SDHCI_RESET_DATA);
sdhci_end_tuning(host);
spin_unlock_irqrestore(&host->lock, flags);
mmc_abort_tuning(host->mmc, opcode);
spin_lock_irqsave(&host->lock, flags);
}
/*
* We use sdhci_send_tuning() because mmc_send_tuning() is not a good fit. SDHCI
* tuning command does not have a data payload (or rather the hardware does it
* automatically) so mmc_send_tuning() will return -EIO. Also the tuning command
* interrupt setup is different to other commands and there is no timeout
* interrupt so special handling is needed.
*/
static void sdhci_send_tuning(struct sdhci_host *host, u32 opcode,
unsigned long flags)
{
struct mmc_host *mmc = host->mmc;
struct mmc_command cmd = {0};
struct mmc_request mrq = {NULL};
cmd.opcode = opcode;
cmd.flags = MMC_RSP_R1 | MMC_CMD_ADTC;
cmd.mrq = &mrq;
mrq.cmd = &cmd;
/*
* In response to CMD19, the card sends 64 bytes of tuning
* block to the Host Controller. So we set the block size
* to 64 here.
*/
if (cmd.opcode == MMC_SEND_TUNING_BLOCK_HS200) {
if (mmc->ios.bus_width == MMC_BUS_WIDTH_8)
sdhci_writew(host, SDHCI_MAKE_BLKSZ(7, 128),
SDHCI_BLOCK_SIZE);
else if (mmc->ios.bus_width == MMC_BUS_WIDTH_4)
sdhci_writew(host, SDHCI_MAKE_BLKSZ(7, 64),
SDHCI_BLOCK_SIZE);
} else {
sdhci_writew(host, SDHCI_MAKE_BLKSZ(7, 64),
SDHCI_BLOCK_SIZE);
}
/*
* The tuning block is sent by the card to the host controller.
* So we set the TRNS_READ bit in the Transfer Mode register.
* This also takes care of setting DMA Enable and Multi Block
* Select in the same register to 0.
*/
sdhci_writew(host, SDHCI_TRNS_READ, SDHCI_TRANSFER_MODE);
sdhci_send_command(host, &cmd);
host->cmd = NULL;
sdhci_del_timer(host, &mrq);
host->tuning_done = 0;
spin_unlock_irqrestore(&host->lock, flags);
/* Wait for Buffer Read Ready interrupt */
wait_event_timeout(host->buf_ready_int, (host->tuning_done == 1),
msecs_to_jiffies(50));
spin_lock_irqsave(&host->lock, flags);
}
static int sdhci_execute_tuning(struct mmc_host *mmc, u32 opcode)
{
struct sdhci_host *host = mmc_priv(mmc);
@ -2011,105 +2127,24 @@ static int sdhci_execute_tuning(struct mmc_host *mmc, u32 opcode)
return err;
}
ctrl = sdhci_readw(host, SDHCI_HOST_CONTROL2);
ctrl |= SDHCI_CTRL_EXEC_TUNING;
if (host->quirks2 & SDHCI_QUIRK2_TUNING_WORK_AROUND)
ctrl |= SDHCI_CTRL_TUNED_CLK;
sdhci_writew(host, ctrl, SDHCI_HOST_CONTROL2);
/*
* As per the Host Controller spec v3.00, tuning command
* generates Buffer Read Ready interrupt, so enable that.
*
* Note: The spec clearly says that when tuning sequence
* is being performed, the controller does not generate
* interrupts other than Buffer Read Ready interrupt. But
* to make sure we don't hit a controller bug, we _only_
* enable Buffer Read Ready interrupt here.
*/
sdhci_writel(host, SDHCI_INT_DATA_AVAIL, SDHCI_INT_ENABLE);
sdhci_writel(host, SDHCI_INT_DATA_AVAIL, SDHCI_SIGNAL_ENABLE);
sdhci_start_tuning(host);
/*
* Issue CMD19 repeatedly till Execute Tuning is set to 0 or the number
* of loops reaches 40 times.
*/
do {
struct mmc_command cmd = {0};
struct mmc_request mrq = {NULL};
cmd.opcode = opcode;
cmd.arg = 0;
cmd.flags = MMC_RSP_R1 | MMC_CMD_ADTC;
cmd.retries = 0;
cmd.data = NULL;
cmd.mrq = &mrq;
cmd.error = 0;
if (tuning_loop_counter-- == 0)
break;
mrq.cmd = &cmd;
/*
* In response to CMD19, the card sends 64 bytes of tuning
* block to the Host Controller. So we set the block size
* to 64 here.
*/
if (cmd.opcode == MMC_SEND_TUNING_BLOCK_HS200) {
if (mmc->ios.bus_width == MMC_BUS_WIDTH_8)
sdhci_writew(host, SDHCI_MAKE_BLKSZ(7, 128),
SDHCI_BLOCK_SIZE);
else if (mmc->ios.bus_width == MMC_BUS_WIDTH_4)
sdhci_writew(host, SDHCI_MAKE_BLKSZ(7, 64),
SDHCI_BLOCK_SIZE);
} else {
sdhci_writew(host, SDHCI_MAKE_BLKSZ(7, 64),
SDHCI_BLOCK_SIZE);
}
/*
* The tuning block is sent by the card to the host controller.
* So we set the TRNS_READ bit in the Transfer Mode register.
* This also takes care of setting DMA Enable and Multi Block
* Select in the same register to 0.
*/
sdhci_writew(host, SDHCI_TRNS_READ, SDHCI_TRANSFER_MODE);
sdhci_send_command(host, &cmd);
host->cmd = NULL;
sdhci_del_timer(host, &mrq);
spin_unlock_irqrestore(&host->lock, flags);
/* Wait for Buffer Read Ready interrupt */
wait_event_timeout(host->buf_ready_int,
(host->tuning_done == 1),
msecs_to_jiffies(50));
spin_lock_irqsave(&host->lock, flags);
sdhci_send_tuning(host, opcode, flags);
if (!host->tuning_done) {
pr_info(DRIVER_NAME ": Timeout waiting for Buffer Read Ready interrupt during tuning procedure, falling back to fixed sampling clock\n");
ctrl = sdhci_readw(host, SDHCI_HOST_CONTROL2);
ctrl &= ~SDHCI_CTRL_TUNED_CLK;
ctrl &= ~SDHCI_CTRL_EXEC_TUNING;
sdhci_writew(host, ctrl, SDHCI_HOST_CONTROL2);
sdhci_do_reset(host, SDHCI_RESET_CMD);
sdhci_do_reset(host, SDHCI_RESET_DATA);
sdhci_writel(host, host->ier, SDHCI_INT_ENABLE);
sdhci_writel(host, host->ier, SDHCI_SIGNAL_ENABLE);
spin_unlock_irqrestore(&host->lock, flags);
mmc_abort_tuning(mmc, opcode);
spin_lock_irqsave(&host->lock, flags);
sdhci_abort_tuning(host, opcode, flags);
goto out;
}
host->tuning_done = 0;
ctrl = sdhci_readw(host, SDHCI_HOST_CONTROL2);
/* eMMC spec does not require a delay between tuning cycles */
@ -2121,18 +2156,15 @@ static int sdhci_execute_tuning(struct mmc_host *mmc, u32 opcode)
* The Host Driver has exhausted the maximum number of loops allowed,
* so use fixed sampling frequency.
*/
if (tuning_loop_counter < 0) {
ctrl &= ~SDHCI_CTRL_TUNED_CLK;
ctrl &= ~SDHCI_CTRL_EXEC_TUNING;
sdhci_writew(host, ctrl, SDHCI_HOST_CONTROL2);
}
if (!(ctrl & SDHCI_CTRL_TUNED_CLK))
if (tuning_loop_counter < 0)
sdhci_reset_tuning(host);
if (tuning_loop_counter < 0 || !(ctrl & SDHCI_CTRL_TUNED_CLK))
pr_info(DRIVER_NAME ": Tuning procedure failed, falling back to fixed sampling clock\n");
out:
host->mmc->retune_period = tuning_count;
sdhci_writel(host, host->ier, SDHCI_INT_ENABLE);
sdhci_writel(host, host->ier, SDHCI_SIGNAL_ENABLE);
sdhci_end_tuning(host);
out_unlock:
spin_unlock_irqrestore(&host->lock, flags);
return err;