Hosts which support re-tuning mode 2 has the capability to indicate
the re-tuning timing by issuing re-tuning request during data transfers.
During non-data transfers, re-tuning timing is determined by either
re-tuning timer or re-tuning request.
Since there is no way to determine the host's capability to generate
re-tuning request during non-data transfers, we will start the re-tuning
timer by default for re-tuning mode 2. If we ever received a re-tuning
request during non-data transfers, that means the host is also capable
of generating re-tuning request for non-data transfers, we will then
deactivate the re-tuning timer altogether.
The SDHCI_RETUNING_TIMER flag is added to indicate the fact that the
host requires re-tuning timer to trigger the re-tuning timing.
The SDHCI_NEEDS_RETUNING, SDHCI_RETUNING_TIMER flags and the max block
count of the host will be restored to their default values since they
are affected by different cards inserted too.
Signed-off-by: Aaron Lu <aaron.lu@xxxxxxx>
---
drivers/mmc/host/sdhci.c | 128 +++++++++++++++++++++++++++++++++------------
drivers/mmc/host/sdhci.h | 3 +
include/linux/mmc/sdhci.h | 4 ++
3 files changed, 102 insertions(+), 33 deletions(-)
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 0e02cc1..f620c72 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -222,6 +222,22 @@ static void sdhci_reinit(struct sdhci_host *host)
{
sdhci_init(host, 0);
sdhci_enable_card_detection(host);
+
+ if (host->version >= SDHCI_SPEC_300) {
+ /*
+ * Clear re-tuning related flags, since these flags
+ * are also affected by different cards inserted
+ */
+ host->flags &= ~(SDHCI_NEEDS_RETUNING |
+ SDHCI_RETUNING_TIMER);
+
+ /*
+ * restore max block count, since it might be
+ * reduced due to re-tuning mode 1 and 2
+ */
+ host->mmc->max_blk_count =
+ (host->quirks & SDHCI_QUIRK_NO_MULTIBLOCK) ? 1 : 65535;
+ }
}
static void sdhci_activate_led(struct sdhci_host *host)
@@ -1245,7 +1261,7 @@ static void sdhci_request(struct mmc_host *mmc, struct mmc_request *mrq)
present_state = sdhci_readl(host, SDHCI_PRESENT_STATE);
/*
- * Check if the re-tuning timer has already expired and there
+ * Check if the re-tuning timing has already arrived and there
* is no on-going data transfer. If so, we need to execute
* tuning procedure before sending command.
*/
@@ -1733,34 +1749,41 @@ static int sdhci_execute_tuning(struct mmc_host *mmc)
out:
/*
- * If this is the very first time we are here, we start the retuning
- * timer. Since only during the first time, SDHCI_NEEDS_RETUNING
- * flag won't be set, we check this condition before actually starting
- * the timer.
+ * If this is the very first time we are here, we setup the
+ * corresponding re-tuning condition. Since only during the
+ * first time, SDHCI_NEEDS_RETUNING flag won't be set.
*/
- if (!(host->flags & SDHCI_NEEDS_RETUNING) && host->tuning_count &&
- (host->tuning_mode == SDHCI_TUNING_MODE_1)) {
- mod_timer(&host->tuning_timer, jiffies +
- host->tuning_count * HZ);
- /* Tuning mode 1 limits the maximum data length to 4MB */
- mmc->max_blk_count = (4 * 1024 * 1024) / mmc->max_blk_size;
+ if (!(host->flags & SDHCI_NEEDS_RETUNING)) {
+ if (host->tuning_count &&
+ host->tuning_mode != SDHCI_TUNING_MODE_RSV) {
+ host->flags |= SDHCI_RETUNING_TIMER;
+ mod_timer(&host->tuning_timer, jiffies +
+ host->tuning_count * HZ);
+ }
+ /* Enable re-tuning event for tuning mode 2 */
+ if (host->tuning_mode == SDHCI_TUNING_MODE_2)
+ ier |= SDHCI_INT_RETUNING;
+ /* Tuning mode 1 and 2 limits the maximum data length to 4MB */
+ if (host->tuning_mode == SDHCI_TUNING_MODE_1 ||
+ host->tuning_mode == SDHCI_TUNING_MODE_2)
+ mmc->max_blk_count = (4 * 1024 * 1024) /
+ mmc->max_blk_size;
} else {
host->flags &= ~SDHCI_NEEDS_RETUNING;
- /* Reload the new initial value for timer */
- if (host->tuning_mode == SDHCI_TUNING_MODE_1)
+ /* Reload the new initial value for re-tuning timer */
+ if (host->flags & SDHCI_RETUNING_TIMER)
mod_timer(&host->tuning_timer, jiffies +
host->tuning_count * HZ);
}
/*
* In case tuning fails, host controllers which support re-tuning can
- * try tuning again at a later time, when the re-tuning timer expires.
+ * try tuning again at a later time, when the re-tuning timing arrives.
* So for these controllers, we return 0. Since there might be other
* controllers who do not have this capability, we return error for
* them.
*/
- if (err && host->tuning_count &&
- host->tuning_mode == SDHCI_TUNING_MODE_1)
+ if (err && (host->tuning_mode != SDHCI_TUNING_MODE_RSV))
err = 0;
sdhci_clear_set_irqs(host, SDHCI_INT_DATA_AVAIL, ier);
@@ -2050,6 +2073,18 @@ static void sdhci_data_irq(struct sdhci_host *host, u32 intmask)
}
}
+ /*
+ * Reload re-tuning timer if transfer complete
+ * occured for re-tuning mode 2
+ */
+ if ((host->flags & SDHCI_RETUNING_TIMER) &&
+ (host->tuning_mode == SDHCI_TUNING_MODE_2) &&
+ (intmask & SDHCI_INT_DATA_END)) {
+ mod_timer(&host->tuning_timer, jiffies +
+ host->tuning_count * HZ);
+ host->flags &= ~SDHCI_NEEDS_RETUNING;
+ }
+
if (!host->data) {
/*
* The "data complete" interrupt is also used to
@@ -2206,6 +2241,23 @@ static irqreturn_t sdhci_irq(int irq, void *dev_id)
intmask &= ~SDHCI_INT_CARD_INT;
+ if (intmask & SDHCI_INT_RETUNING) {
+ host->flags |= SDHCI_NEEDS_RETUNING;
+ if ((host->flags & SDHCI_RETUNING_TIMER) &&
+ (host->tuning_mode == SDHCI_TUNING_MODE_2)) {
+ u32 state = sdhci_readl(host, SDHCI_PRESENT_STATE);
+ /*
+ * If host is capable of generating re-tuning
+ * request during non-data transfers, there is
+ * no need to use re-tuning timer
+ */
+ if (!(state & SDHCI_DATA_ACTIVE))
+ host->flags &= ~SDHCI_RETUNING_TIMER;
+ }
+ }
+
+ intmask &= ~SDHCI_INT_RETUNING;
+
if (intmask) {
printk(KERN_ERR "%s: Unexpected interrupt 0x%08x.\n",
mmc_hostname(host->mmc), intmask);
@@ -2243,12 +2295,14 @@ int sdhci_suspend_host(struct sdhci_host *host, pm_message_t state)
sdhci_disable_card_detection(host);
- /* Disable tuning since we are suspending */
- if (host->version >= SDHCI_SPEC_300 && host->tuning_count &&
- host->tuning_mode == SDHCI_TUNING_MODE_1) {
+ /* Disable re-tuning since we are suspending */
+ if ((host->version >= SDHCI_SPEC_300) &&
+ (host->tuning_mode != SDHCI_TUNING_MODE_RSV)) {
host->flags &= ~SDHCI_NEEDS_RETUNING;
- mod_timer(&host->tuning_timer, jiffies +
- host->tuning_count * HZ);
+ if (host->flags & SDHCI_RETUNING_TIMER)
+ del_timer_sync(&host->tuning_timer);
+ if (host->tuning_mode == SDHCI_TUNING_MODE_2)
+ sdhci_mask_irqs(host, SDHCI_INT_RETUNING);
}
ret = mmc_suspend_host(host->mmc);
@@ -2292,11 +2346,6 @@ int sdhci_resume_host(struct sdhci_host *host)
ret = mmc_resume_host(host->mmc);
sdhci_enable_card_detection(host);
- /* Set the re-tuning expiration flag */
- if ((host->version >= SDHCI_SPEC_300) && host->tuning_count &&
- (host->tuning_mode == SDHCI_TUNING_MODE_1))
- host->flags |= SDHCI_NEEDS_RETUNING;
-
return ret;
}
@@ -2570,12 +2619,22 @@ int sdhci_add_host(struct sdhci_host *host)
host->tuning_count = (caps[1] & SDHCI_RETUNING_TIMER_COUNT_MASK) >>
SDHCI_RETUNING_TIMER_COUNT_SHIFT;
- /*
- * In case Re-tuning Timer is not disabled, the actual value of
- * re-tuning timer will be 2 ^ (n - 1).
- */
- if (host->tuning_count)
- host->tuning_count = 1 << (host->tuning_count - 1);
+ if (host->tuning_count) {
+ /*
+ * In case re-tuning timer is not disabled,
+ * the actual value of re-tuning timer will be:
+ * 0x1 - 0xb: 2 ^ (n - 1)
+ * 0xc - 0xe: reserved
+ * 0xf: get the value from other source
+ */
+ if (host->tuning_count <= 0xb)
+ host->tuning_count = 1 << (host->tuning_count - 1);
+ else if (host->tuning_count == 0xf)
+ host->tuning_count = host->ops->get_tuning_count ?
+ host->ops->get_tuning_count(host) : 0;
+ else
+ host->tuning_count = 0;
+ }
/* Re-tuning mode supported by the Host Controller */
host->tuning_mode = (caps[1] & SDHCI_RETUNING_MODE_MASK) >>
@@ -2816,6 +2875,9 @@ void sdhci_remove_host(struct sdhci_host *host, int dead)
sdhci_disable_card_detection(host);
+ if (host->tuning_mode == SDHCI_TUNING_MODE_2)
+ sdhci_mask_irqs(host, SDHCI_INT_RETUNING);
+
mmc_remove_host(host->mmc);
#ifdef SDHCI_USE_LEDS_CLASS
@@ -2828,7 +2890,7 @@ void sdhci_remove_host(struct sdhci_host *host, int dead)
free_irq(host->irq, host);
del_timer_sync(&host->timer);
- if (host->version >= SDHCI_SPEC_300)
+ if (host->flags & SDHCI_RETUNING_TIMER)
del_timer_sync(&host->tuning_timer);
tasklet_kill(&host->card_tasklet);
diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
index 745c42f..ef4a0a3 100644
--- a/drivers/mmc/host/sdhci.h
+++ b/drivers/mmc/host/sdhci.h
@@ -64,6 +64,7 @@
#define SDHCI_PRESENT_STATE 0x24
#define SDHCI_CMD_INHIBIT 0x00000001
#define SDHCI_DATA_INHIBIT 0x00000002
+#define SDHCI_DATA_ACTIVE 0x00000004
#define SDHCI_DOING_WRITE 0x00000100
#define SDHCI_DOING_READ 0x00000200
#define SDHCI_SPACE_AVAILABLE 0x00000400
@@ -126,6 +127,7 @@
#define SDHCI_INT_CARD_INSERT 0x00000040
#define SDHCI_INT_CARD_REMOVE 0x00000080
#define SDHCI_INT_CARD_INT 0x00000100
+#define SDHCI_INT_RETUNING 0x00001000
#define SDHCI_INT_ERROR 0x00008000
#define SDHCI_INT_TIMEOUT 0x00010000
#define SDHCI_INT_CRC 0x00020000
@@ -273,6 +275,7 @@ struct sdhci_ops {
void (*platform_reset_enter)(struct sdhci_host *host, u8 mask);
void (*platform_reset_exit)(struct sdhci_host *host, u8 mask);
int (*set_uhs_signaling)(struct sdhci_host *host, unsigned int uhs);
+ int (*get_tuning_count)(struct sdhci_host *host);
};
diff --git a/include/linux/mmc/sdhci.h b/include/linux/mmc/sdhci.h
index 5666f3a..938a4f5 100644
--- a/include/linux/mmc/sdhci.h
+++ b/include/linux/mmc/sdhci.h
@@ -115,6 +115,7 @@ struct sdhci_host {
#define SDHCI_NEEDS_RETUNING (1<<5) /* Host needs retuning */
#define SDHCI_AUTO_CMD12 (1<<6) /* Auto CMD12 support */
#define SDHCI_AUTO_CMD23 (1<<7) /* Auto CMD23 support */
+#define SDHCI_RETUNING_TIMER (1<<8) /* Host uses re-tuning timer */
unsigned int version; /* SDHCI spec. version */
@@ -158,6 +159,9 @@ struct sdhci_host {
unsigned int tuning_count; /* Timer count for re-tuning */
unsigned int tuning_mode; /* Re-tuning mode supported by host */
#define SDHCI_TUNING_MODE_1 0
+#define SDHCI_TUNING_MODE_2 1
+#define SDHCI_TUNING_MODE_3 2
+#define SDHCI_TUNING_MODE_RSV 3
struct timer_list tuning_timer; /* Timer for tuning */
unsigned long private[0] ____cacheline_aligned;
--
1.7.1
--
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