Andrew Morton wrote:
On Mon, 23 Aug 2010 21:48:29 +0100
Matt Fleming <matt@xxxxxxxxxxxxxxxxx> wrote:
On Sat, Aug 21, 2010 at 06:37:45PM -0400, Chris Ball wrote:
Hi,
> Hm is there some problem with this patch or has the processing of
> it simply stalled? When I read the thread I cannot see Hanumaths
> answers on the list but it looks mainly like the patch is OK and
> there is some chit-chat.
>
> Can it be picked up? Everyone is going to need DDR MMC for their
> eMMCs soon-ish.
I'd like to dedicate more time to mmc/. Do you think it'd be useful
for me to catch all the patches sent to linux-mmc@ into a public Git
tree, and periodically report on what went upstream via akpm and
what's still waiting?
It's possible Andrew has a reason that hasn't been picked up yet.
Kyungmin Park's questions didn't seem adequately answered and the
discussion kind of died.
I updated the patch and merged it, but I'd like the outstanding
question(s) resolved. ie: why do we add MMC_DDR_MODE, set it in
brq.data.flags and then never use it?
I am not able to test DDR mode but it look to me that the patch
should be changed. Here is a fix:
From 8253aa16b1ab15974a3ba8f33566fe8e2cca29e6 Mon Sep 17 00:00:00 2001
From: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Date: Tue, 24 Aug 2010 13:20:26 +0300
Subject: [PATCH] mmc: Fix Dual Data Rate (DDR) support
The DDR support patch needs the following fixes:
- The block driver does not need to know about DDR, any more
than it needs to know about bus width.
- Not only the card must be switched to DDR mode. The host
controller must also be configured, which is done through
the 'set_ios()' function.
- Do not set the DDR mode state until after the switch command
is successful.
- Setting block length is not supported in DDR mode. Make that
a core function and change the other place it is used (mmc_test)
also.
Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
---
drivers/mmc/card/block.c | 19 +++----------------
drivers/mmc/card/mmc_test.c | 12 +-----------
drivers/mmc/core/bus.c | 6 ++++--
drivers/mmc/core/core.c | 28 ++++++++++++++++++++++++++--
drivers/mmc/core/core.h | 1 +
drivers/mmc/core/mmc.c | 21 +++++++++++----------
include/linux/mmc/core.h | 3 ++-
include/linux/mmc/host.h | 5 +++++
8 files changed, 53 insertions(+), 42 deletions(-)
diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c
index 24f39d7..1ec93bb 100644
--- a/drivers/mmc/card/block.c
+++ b/drivers/mmc/card/block.c
@@ -373,8 +373,6 @@ static int mmc_blk_issue_rw_rq(struct mmc_queue *mq, struct request *req)
readcmd = MMC_READ_SINGLE_BLOCK;
writecmd = MMC_WRITE_BLOCK;
}
- if (mmc_card_ddr_mode(card))
- brq.data.flags |= MMC_DDR_MODE;
if (rq_data_dir(req) == READ) {
brq.cmd.opcode = readcmd;
brq.data.flags |= MMC_DATA_READ;
@@ -652,26 +650,15 @@ static struct mmc_blk_data *mmc_blk_alloc(struct mmc_card *card)
static int
mmc_blk_set_blksize(struct mmc_blk_data *md, struct mmc_card *card)
{
- struct mmc_command cmd;
int err;
- /*
- * Block-addressed and ddr mode supported cards
- * ignore MMC_SET_BLOCKLEN.
- */
- if (mmc_card_blockaddr(card) || mmc_card_ddr_mode(card))
- return 0;
-
mmc_claim_host(card->host);
- cmd.opcode = MMC_SET_BLOCKLEN;
- cmd.arg = 512;
- cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
- err = mmc_wait_for_cmd(card->host, &cmd, 5);
+ err = mmc_set_blocklen(card, 512);
mmc_release_host(card->host);
if (err) {
- printk(KERN_ERR "%s: unable to set block size to %d: %d\n",
- md->disk->disk_name, cmd.arg, err);
+ printk(KERN_ERR "%s: unable to set block size to 512: %d\n",
+ md->disk->disk_name, err);
return -EINVAL;
}
diff --git a/drivers/mmc/card/mmc_test.c b/drivers/mmc/card/mmc_test.c
index 5dd8576..f80b759 100644
--- a/drivers/mmc/card/mmc_test.c
+++ b/drivers/mmc/card/mmc_test.c
@@ -100,17 +100,7 @@ struct mmc_test_card {
*/
static int mmc_test_set_blksize(struct mmc_test_card *test, unsigned size)
{
- struct mmc_command cmd;
- int ret;
-
- cmd.opcode = MMC_SET_BLOCKLEN;
- cmd.arg = size;
- cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
- ret = mmc_wait_for_cmd(test->card->host, &cmd, 0);
- if (ret)
- return ret;
-
- return 0;
+ return mmc_set_blocklen(test->card, size);
}
/*
diff --git a/drivers/mmc/core/bus.c b/drivers/mmc/core/bus.c
index 7cd9749..dc36f39 100644
--- a/drivers/mmc/core/bus.c
+++ b/drivers/mmc/core/bus.c
@@ -254,14 +254,16 @@ int mmc_add_card(struct mmc_card *card)
}
if (mmc_host_is_spi(card->host)) {
- printk(KERN_INFO "%s: new %s%s card on SPI\n",
+ printk(KERN_INFO "%s: new %s%s%s card on SPI\n",
mmc_hostname(card->host),
mmc_card_highspeed(card) ? "high speed " : "",
+ mmc_card_ddr_mode(card) ? "DDR " : "",
type);
} else {
- printk(KERN_INFO "%s: new %s%s card at address %04x\n",
+ printk(KERN_INFO "%s: new %s%s%s card at address %04x\n",
mmc_hostname(card->host),
mmc_card_highspeed(card) ? "high speed " : "",
+ mmc_card_ddr_mode(card) ? "DDR " : "",
type, card->rca);
}
diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index 5db49b1..8519480 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -650,14 +650,23 @@ void mmc_set_bus_mode(struct mmc_host *host, unsigned int mode)
}
/*
- * Change data bus width of a host.
+ * Change data bus width and DDR mode of a host.
*/
-void mmc_set_bus_width(struct mmc_host *host, unsigned int width)
+void mmc_set_bus_width_ddr(struct mmc_host *host, unsigned int width, int ddr)
{
host->ios.bus_width = width;
+ host->ios.ddr = ddr ? MMC_DDR_MODE : MMC_SDR_MODE;
mmc_set_ios(host);
}
+/*
+ * Change data bus width of a host.
+ */
+void mmc_set_bus_width(struct mmc_host *host, unsigned int width)
+{
+ mmc_set_bus_width_ddr(host, width, 0);
+}
+
/**
* mmc_vdd_to_ocrbitnum - Convert a voltage to the OCR bit number
* @vdd: voltage (mV)
@@ -1397,6 +1406,21 @@ int mmc_erase_group_aligned(struct mmc_card *card, unsigned int from,
}
EXPORT_SYMBOL(mmc_erase_group_aligned);
+int mmc_set_blocklen(struct mmc_card *card, unsigned int blocklen)
+{
+ struct mmc_command cmd;
+
+ if (mmc_card_blockaddr(card) || mmc_card_ddr_mode(card))
+ return 0;
+
+ memset(&cmd, 0, sizeof(struct mmc_command));
+ cmd.opcode = MMC_SET_BLOCKLEN;
+ cmd.arg = blocklen;
+ cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
+ return mmc_wait_for_cmd(card->host, &cmd, 5);
+}
+EXPORT_SYMBOL(mmc_set_blocklen);
+
void mmc_rescan(struct work_struct *work)
{
struct mmc_host *host =
diff --git a/drivers/mmc/core/core.h b/drivers/mmc/core/core.h
index 9d9eef5..68150c9 100644
--- a/drivers/mmc/core/core.h
+++ b/drivers/mmc/core/core.h
@@ -35,6 +35,7 @@ void mmc_set_chip_select(struct mmc_host *host, int mode);
void mmc_set_clock(struct mmc_host *host, unsigned int hz);
void mmc_set_bus_mode(struct mmc_host *host, unsigned int mode);
void mmc_set_bus_width(struct mmc_host *host, unsigned int width);
+void mmc_set_bus_width_ddr(struct mmc_host *host, unsigned int width, int ddr);
u32 mmc_select_voltage(struct mmc_host *host, u32 ocr);
void mmc_set_timing(struct mmc_host *host, unsigned int timing);
diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index dcfc921..998c0d3 100644
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -375,7 +375,7 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr,
struct mmc_card *oldcard)
{
struct mmc_card *card;
- int err;
+ int err, ddr = 0;
u32 cid[4];
unsigned int max_dtr;
@@ -518,32 +518,32 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr,
mmc_set_clock(host, max_dtr);
/*
- * Activate DDR50 mode (if supported).
+ * Indicate DDR mode (if supported).
*/
if (mmc_card_highspeed(card)) {
if ((card->ext_csd.card_type & EXT_CSD_CARD_TYPE_DDR_1_8V)
&& (host->caps & (MMC_CAP_1_8V_DDR)))
- mmc_card_set_ddr_mode(card);
+ ddr = 1;
else if ((card->ext_csd.card_type & EXT_CSD_CARD_TYPE_DDR_1_2V)
&& (host->caps & (MMC_CAP_1_2V_DDR)))
- mmc_card_set_ddr_mode(card);
+ ddr = 1;
}
/*
- * Activate wide bus (if supported).
+ * Activate wide bus and DDR (if supported).
*/
if ((card->csd.mmca_vsn >= CSD_SPEC_VER_4) &&
(host->caps & (MMC_CAP_4_BIT_DATA | MMC_CAP_8_BIT_DATA))) {
unsigned ext_csd_bit, bus_width;
if (host->caps & MMC_CAP_8_BIT_DATA) {
- if (mmc_card_ddr_mode(card))
+ if (ddr)
ext_csd_bit = EXT_CSD_DDR_BUS_WIDTH_8;
else
ext_csd_bit = EXT_CSD_BUS_WIDTH_8;
bus_width = MMC_BUS_WIDTH_8;
} else {
- if (mmc_card_ddr_mode(card))
+ if (ddr)
ext_csd_bit = EXT_CSD_DDR_BUS_WIDTH_4;
else
ext_csd_bit = EXT_CSD_BUS_WIDTH_4;
@@ -557,12 +557,13 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr,
goto free_card;
if (err) {
- printk(KERN_WARNING "%s: switch to bus width %d "
+ printk(KERN_WARNING "%s: switch to bus width %d ddr %d "
"failed\n", mmc_hostname(card->host),
- 1 << bus_width);
+ 1 << bus_width, ddr);
err = 0;
} else {
- mmc_set_bus_width(card->host, bus_width);
+ mmc_card_set_ddr_mode(card);
+ mmc_set_bus_width_ddr(card->host, bus_width, ddr);
}
}
diff --git a/include/linux/mmc/core.h b/include/linux/mmc/core.h
index 17bb4c2..64e013f 100644
--- a/include/linux/mmc/core.h
+++ b/include/linux/mmc/core.h
@@ -109,7 +109,6 @@ struct mmc_data {
#define MMC_DATA_WRITE (1 << 8)
#define MMC_DATA_READ (1 << 9)
#define MMC_DATA_STREAM (1 << 10)
-#define MMC_DDR_MODE (1 << 11)
unsigned int bytes_xfered;
@@ -154,6 +153,8 @@ extern int mmc_can_secure_erase_trim(struct mmc_card *card);
extern int mmc_erase_group_aligned(struct mmc_card *card, unsigned int from,
unsigned int nr);
+extern int mmc_set_blocklen(struct mmc_card *card, unsigned int blocklen);
+
extern void mmc_set_data_timeout(struct mmc_data *, const struct mmc_card *);
extern unsigned int mmc_align_data_size(struct mmc_card *, unsigned int);
diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index 09dbb90..aa1a747 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -50,6 +50,11 @@ struct mmc_ios {
#define MMC_TIMING_LEGACY 0
#define MMC_TIMING_MMC_HS 1
#define MMC_TIMING_SD_HS 2
+
+ unsigned char ddr; /* dual data rate used */
+
+#define MMC_SDR_MODE 0
+#define MMC_DDR_MODE 1
};
struct mmc_host_ops {
--
1.6.3.3
--
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