Hi Jaehoon,
On Mon, Sep 17 2012, Jaehoon Chung wrote:
> Enable eMMC background operations (BKOPS) feature.
>
> If URGENT_BKOPS is set after a response, note that BKOPS
> are required. Immediately run BKOPS if required.
> read/write operations should be requested during BKOPS(LEVEL-1),
> then issue HPI to interrupt the ongoing BKOPS
> and service the foreground operation.
> (This patch is only control the LEVEL2/3.)
>
> When repeating the writing 1GB data, at a certain time, performance is decreased.
> At that time, card is also triggered the Level-3 or Level-2.
> After running bkops, performance is recovered.
>
> Future considerations
> * Check BKOPS_LEVEL=1 and start BKOPS in a preventive manner.
> * Interrupt ongoing BKOPS before powering off the card.
> * How get BKOPS_STATUS value.(periodically send ext_csd command?)
> * If use periodic bkops, also consider runtime_pm control.
>
> Signed-off-by: Jaehoon Chung <jh80.chung@xxxxxxxxxxx>
> Signed-off-by: Kyungmin Park <kyungmin.park@xxxxxxxxxxx>
> Signed-off-by: Konstantin Dorfman <kdorfman@xxxxxxxxxxxxxx>
> Reviewed-by: Maya Erez <merez@xxxxxxxxxxxxxx>
Thanks, looks good now. Is it okay if I apply this stylistic patch
before pushing to mmc-next?
diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index 4749557..044cd01 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -43,8 +43,8 @@
#include "sdio_ops.h"
/*
- * The Background operation can take a long time, depends on the house keeping
- * operations the card has to peform
+ * Background operations can take a long time, depending on the housekeeping
+ * operations the card has to perform.
*/
#define MMC_BKOPS_MAX_TIMEOUT (4 * 60 * 1000) /* max time to wait in ms */
@@ -255,11 +255,11 @@ mmc_start_request(struct mmc_host *host, struct mmc_request *mrq)
/**
* mmc_start_bkops - start BKOPS for supported cards
* @card: MMC card to start BKOPS
- * @form_exception: A flags to indicate if this function was
- * called due to an exception raised by the card
+ * @form_exception: A flag to indicate if this function was
+ * called due to an exception raised by the card
*
* Start background operations whenever requested.
- * when the urgent BKOPS bit is set in a R1 command response
+ * When the urgent BKOPS bit is set in a R1 command response
* then background operations should be started immediately.
*/
void mmc_start_bkops(struct mmc_card *card, bool from_exception)
@@ -275,7 +275,7 @@ void mmc_start_bkops(struct mmc_card *card, bool from_exception)
err = mmc_read_bkops_status(card);
if (err) {
- pr_err("%s: Didn't read bkops status : %d\n",
+ pr_err("%s: Failed to read bkops status: %d\n",
mmc_hostname(card->host), err);
return;
}
@@ -283,8 +283,8 @@ void mmc_start_bkops(struct mmc_card *card, bool from_exception)
if (!card->ext_csd.raw_bkops_status)
return;
- if (card->ext_csd.raw_bkops_status < EXT_CSD_BKOPS_LEVEL_2
- && (from_exception))
+ if (card->ext_csd.raw_bkops_status < EXT_CSD_BKOPS_LEVEL_2 &&
+ from_exception)
return;
mmc_claim_host(card->host);
@@ -299,8 +299,8 @@ void mmc_start_bkops(struct mmc_card *card, bool from_exception)
err = __mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
EXT_CSD_BKOPS_START, 1, timeout, use_busy_signal);
if (err) {
- pr_warn("%s: error %d starting bkops\n",
- mmc_hostname(card->host), err);
+ pr_warn("%s: Error %d starting bkops\n",
+ mmc_hostname(card->host), err);
goto out;
}
@@ -429,9 +429,9 @@ struct mmc_async_req *mmc_start_req(struct mmc_host *host,
* Check BKOPS urgency for each R1 response
*/
if (host->card && mmc_card_mmc(host->card) &&
- ((mmc_resp_type(host->areq->mrq->cmd) == MMC_RSP_R1) ||
- (mmc_resp_type(host->areq->mrq->cmd) == MMC_RSP_R1B)) &&
- (host->areq->mrq->cmd->resp[0] & R1_EXCEPTION_EVENT))
+ ((mmc_resp_type(host->areq->mrq->cmd) == MMC_RSP_R1) ||
+ (mmc_resp_type(host->areq->mrq->cmd) == MMC_RSP_R1B)) &&
+ (host->areq->mrq->cmd->resp[0] & R1_EXCEPTION_EVENT))
mmc_start_bkops(host->card, true);
}
@@ -477,7 +477,7 @@ EXPORT_SYMBOL(mmc_wait_for_req);
* @card: the MMC card associated with the HPI transfer
*
* Issued High Priority Interrupt, and check for card status
- * util out-of prg-state.
+ * until out-of prg-state.
*/
int mmc_interrupt_hpi(struct mmc_card *card)
{
@@ -572,8 +572,8 @@ EXPORT_SYMBOL(mmc_wait_for_cmd);
* mmc_stop_bkops - stop ongoing BKOPS
* @card: MMC card to check BKOPS
*
- * Send HPI command to stop ongoing background operations,
- * to allow rapid servicing of foreground operations,e.g. read/
+ * Send HPI command to stop ongoing background operations to
+ * allow rapid servicing of foreground operations, e.g. read/
* writes. Wait until the card comes out of the programming state
* to avoid errors in servicing read/write requests.
*/
@@ -585,8 +585,8 @@ int mmc_stop_bkops(struct mmc_card *card)
err = mmc_interrupt_hpi(card);
/*
- * if err is EINVAL, it's status that can't issue HPI.
- * it should complete the BKOPS.
+ * If err is EINVAL, we can't issue an HPI.
+ * It should complete the BKOPS.
*/
if (!err || (err == -EINVAL)) {
mmc_card_clr_doing_bkops(card);
@@ -603,12 +603,12 @@ int mmc_read_bkops_status(struct mmc_card *card)
u8 *ext_csd;
/*
- * In future work, we should be consider storing the entire ext_csd.
+ * In future work, we should consider storing the entire ext_csd.
*/
ext_csd = kmalloc(512, GFP_KERNEL);
if (!ext_csd) {
- pr_err("%s: could not allocate a buffer to "
- "receive the ext_csd.\n", mmc_hostname(card->host));
+ pr_err("%s: could not allocate buffer to receive the ext_csd.\n",
+ mmc_hostname(card->host));
return -ENOMEM;
}
@@ -2470,15 +2470,14 @@ int mmc_suspend_host(struct mmc_host *host)
mmc_bus_get(host);
if (host->bus_ops && !host->bus_dead) {
-
if (host->bus_ops->suspend) {
if (mmc_card_doing_bkops(host->card)) {
err = mmc_stop_bkops(host->card);
if (err)
goto out;
}
- }
err = host->bus_ops->suspend(host);
+ }
if (err == -ENOSYS || !host->bus_ops->resume) {
/*
@@ -2566,10 +2565,10 @@ int mmc_pm_notify(struct notifier_block *notify_block,
case PM_HIBERNATION_PREPARE:
case PM_SUSPEND_PREPARE:
if (host->card && mmc_card_mmc(host->card) &&
- mmc_card_doing_bkops(host->card)) {
+ mmc_card_doing_bkops(host->card)) {
err = mmc_stop_bkops(host->card);
if (err) {
- pr_err("%s didn't stop bkops\n",
+ pr_err("%s: didn't stop bkops\n",
mmc_hostname(host));
return err;
}
diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index 9c5caa6..7509de1 100644
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -463,15 +463,15 @@ static int mmc_read_ext_csd(struct mmc_card *card, u8 *ext_csd)
}
if (card->ext_csd.rev >= 5) {
- /* check whether the eMMC card support BKOPS */
+ /* check whether the eMMC card supports BKOPS */
if (ext_csd[EXT_CSD_BKOPS_SUPPORT] & 0x1) {
card->ext_csd.bkops = 1;
card->ext_csd.bkops_en = ext_csd[EXT_CSD_BKOPS_EN];
card->ext_csd.raw_bkops_status =
ext_csd[EXT_CSD_BKOPS_STATUS];
if (!card->ext_csd.bkops_en)
- pr_info("%s: Didn't set BKOPS_EN bit!\n",
- mmc_hostname(card->host));
+ pr_info("%s: BKOPS_EN bit is not set\n",
+ mmc_hostname(card->host));
}
/* check whether the eMMC card supports HPI */
--
Chris Ball <cjb@xxxxxxxxxx> <http://printf.net/>
One Laptop Per Child
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