[U-Boot] [PATCH v2 1/1] ARM: kirkwood: mvebu_mmc: Speed up access time
Gérald Kerma
drEagle at doukki.net
Thu Dec 4 16:03:39 CET 2014
Review delays and timeouts.
Get around 20 x faster access on Sheevaplug tests.
Changes in v2:
- increase number of loops
- remove initial delay
Changes in v1:
- review all loops, delays and timeouts
Signed-off-by: Gérald Kerma <drEagle at doukki.net>
---
drivers/mmc/mvebu_mmc.c | 66 +++++++++++++++++++++++++++++--------------------
1 file changed, 39 insertions(+), 27 deletions(-)
diff --git a/drivers/mmc/mvebu_mmc.c b/drivers/mmc/mvebu_mmc.c
index 9f98c3f..b636be6 100644
--- a/drivers/mmc/mvebu_mmc.c
+++ b/drivers/mmc/mvebu_mmc.c
@@ -23,6 +23,10 @@ DECLARE_GLOBAL_DATA_PTR;
#define MVEBU_TARGET_DRAM 0
+#define TIMEOUT_LOOP 1000000000000000000 /* maximum loops */
+#define TIMEOUT_WAIT 100 /* wait 100 us */
+#define TIMEOUT_START 100 /* wait 100 us */
+
static void mvebu_mmc_write(u32 offs, u32 val)
{
writel(val, CONFIG_SYS_MMC_BASE + (offs));
@@ -63,7 +67,7 @@ static int mvebu_mmc_setup_data(struct mmc_data *data)
static int mvebu_mmc_send_cmd(struct mmc *mmc, struct mmc_cmd *cmd,
struct mmc_data *data)
{
- int timeout = 10;
+ u64 timeout = TIMEOUT_LOOP;
ushort waittype = 0;
ushort resptype = 0;
ushort xfertype = 0;
@@ -72,27 +76,32 @@ static int mvebu_mmc_send_cmd(struct mmc *mmc, struct mmc_cmd *cmd,
debug("cmdidx [0x%x] resp_type[0x%x] cmdarg[0x%x]\n",
cmd->cmdidx, cmd->resp_type, cmd->cmdarg);
- udelay(10*1000);
-
debug("%s: cmd %d (hw state 0x%04x)\n", DRIVER_NAME,
cmd->cmdidx, mvebu_mmc_read(SDIO_HW_STATE));
+ /* Clear status */
+ mvebu_mmc_write(SDIO_NOR_INTR_STATUS, SDIO_POLL_MASK);
+ mvebu_mmc_write(SDIO_ERR_INTR_STATUS, SDIO_POLL_MASK);
+
/* Checking if card is busy */
while ((mvebu_mmc_read(SDIO_HW_STATE) & CARD_BUSY)) {
+ timeout--;
+ udelay(TIMEOUT_START);
if (timeout == 0) {
printf("%s: card busy!\n", DRIVER_NAME);
return -1;
}
- timeout--;
- udelay(1000);
}
/* Set up for a data transfer if we have one */
if (data) {
int err = mvebu_mmc_setup_data(data);
- if (err)
+ if (err){
+ debug("%s: command DATA error :%x\n",
+ DRIVER_NAME, err);
return err;
+ }
}
resptype = SDIO_CMD_INDEX(cmd->cmdidx);
@@ -148,7 +157,7 @@ static int mvebu_mmc_send_cmd(struct mmc *mmc, struct mmc_cmd *cmd,
mvebu_mmc_write(SDIO_ERR_INTR_EN, SDIO_POLL_MASK);
/* Waiting for completion */
- timeout = 1000000;
+ timeout = TIMEOUT_LOOP;
while (!((mvebu_mmc_read(SDIO_NOR_INTR_STATUS)) & waittype)) {
if (mvebu_mmc_read(SDIO_NOR_INTR_STATUS) & SDIO_NOR_ERROR) {
@@ -156,21 +165,22 @@ static int mvebu_mmc_send_cmd(struct mmc *mmc, struct mmc_cmd *cmd,
DRIVER_NAME, cmd->cmdidx,
mvebu_mmc_read(SDIO_ERR_INTR_STATUS));
if (mvebu_mmc_read(SDIO_ERR_INTR_STATUS) &
- (SDIO_ERR_CMD_TIMEOUT | SDIO_ERR_DATA_TIMEOUT))
+ (SDIO_ERR_CMD_TIMEOUT | SDIO_ERR_DATA_TIMEOUT)){
+ debug("%s: command READ timed out\n",
+ DRIVER_NAME);
return TIMEOUT;
+ }
+ debug("%s: command READ error\n", DRIVER_NAME);
return COMM_ERR;
}
timeout--;
- udelay(1);
- if (timeout <= 0) {
- printf("%s: command timed out\n", DRIVER_NAME);
+ udelay(TIMEOUT_WAIT);
+ if (timeout == 0) {
+ debug("%s: command timed out\n", DRIVER_NAME);
return TIMEOUT;
}
}
- if (mvebu_mmc_read(SDIO_ERR_INTR_STATUS) &
- (SDIO_ERR_CMD_TIMEOUT | SDIO_ERR_DATA_TIMEOUT))
- return TIMEOUT;
/* Handling response */
if (cmd->resp_type & MMC_RSP_136) {
@@ -213,6 +223,11 @@ static int mvebu_mmc_send_cmd(struct mmc *mmc, struct mmc_cmd *cmd,
debug("[0x%x] ", cmd->response[3]);
debug("\n");
+ if (mvebu_mmc_read(SDIO_ERR_INTR_STATUS) & SDIO_ERR_CMD_TIMEOUT){
+ debug("%s: command STATUS timed out\n", DRIVER_NAME);
+ return TIMEOUT;
+ }
+
return 0;
}
@@ -236,33 +251,30 @@ static void mvebu_mmc_power_up(void)
/* enable interrupts status */
mvebu_mmc_write(SDIO_NOR_INTR_STATUS, SDIO_POLL_MASK);
mvebu_mmc_write(SDIO_ERR_INTR_STATUS, SDIO_POLL_MASK);
+
+ udelay(10*1000);
}
static void mvebu_mmc_set_clk(unsigned int clock)
{
- unsigned int m;
-
if (clock == 0) {
debug("%s: clock off\n", DRIVER_NAME);
mvebu_mmc_write(SDIO_XFER_MODE, SDIO_XFER_MODE_STOP_CLK);
mvebu_mmc_write(SDIO_CLK_DIV, MVEBU_MMC_BASE_DIV_MAX);
} else {
- m = MVEBU_MMC_BASE_FAST_CLOCK/(2*clock) - 1;
+ u32 m = DIV_ROUND_UP(MVEBU_MMC_BASE_FAST_CLOCK,
+ (2 * clock)) - 1;
if (m > MVEBU_MMC_BASE_DIV_MAX)
m = MVEBU_MMC_BASE_DIV_MAX;
- mvebu_mmc_write(SDIO_CLK_DIV, m & MVEBU_MMC_BASE_DIV_MAX);
+ mvebu_mmc_write(SDIO_CLK_DIV, m);
+ debug("%s: clock (%d) div : %d\n", DRIVER_NAME, clock, m);
}
-
- udelay(10*1000);
}
static void mvebu_mmc_set_bus(unsigned int bus)
{
u32 ctrl_reg = 0;
- ctrl_reg = mvebu_mmc_read(SDIO_HOST_CTRL);
- ctrl_reg &= ~SDIO_HOST_CTRL_DATA_WIDTH_4_BITS;
-
switch (bus) {
case 4:
ctrl_reg |= SDIO_HOST_CTRL_DATA_WIDTH_4_BITS;
@@ -277,7 +289,7 @@ static void mvebu_mmc_set_bus(unsigned int bus)
ctrl_reg &= ~SDIO_HOST_CTRL_LSB_FIRST;
/* default to maximum timeout */
- ctrl_reg |= SDIO_HOST_CTRL_TMOUT(SDIO_HOST_CTRL_TMOUT_MAX);
+ ctrl_reg |= SDIO_HOST_CTRL_TMOUT_MAX;
ctrl_reg |= SDIO_HOST_CTRL_TMOUT_EN;
ctrl_reg |= SDIO_HOST_CTRL_PUSH_PULL_EN;
@@ -293,7 +305,6 @@ static void mvebu_mmc_set_bus(unsigned int bus)
"high-speed" : "");
mvebu_mmc_write(SDIO_HOST_CTRL, ctrl_reg);
- udelay(10*1000);
}
static void mvebu_mmc_set_ios(struct mmc *mmc)
@@ -355,7 +366,7 @@ static void mvebu_window_setup(void)
static int mvebu_mmc_initialize(struct mmc *mmc)
{
- debug("%s: mvebu_mmc_initialize", DRIVER_NAME);
+ debug("%s: mvebu_mmc_initialize\n", DRIVER_NAME);
/*
* Setting host parameters
@@ -398,7 +409,8 @@ static const struct mmc_ops mvebu_mmc_ops = {
static struct mmc_config mvebu_mmc_cfg = {
.name = DRIVER_NAME,
.ops = &mvebu_mmc_ops,
- .f_min = MVEBU_MMC_BASE_FAST_CLOCK / MVEBU_MMC_BASE_DIV_MAX,
+ .f_min = DIV_ROUND_UP(MVEBU_MMC_BASE_FAST_CLOCK,
+ MVEBU_MMC_BASE_DIV_MAX),
.f_max = MVEBU_MMC_CLOCKRATE_MAX,
.voltages = MMC_VDD_32_33 | MMC_VDD_33_34,
.host_caps = MMC_MODE_4BIT | MMC_MODE_HS | MMC_MODE_HC |
--
2.1.3
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