Commit 28d27b79 authored by Gerald Kerma's avatar Gerald Kerma Committed by Pantelis Antoniou

MVEBUMMC : Speed up access time

Get about 40x faster access on SHEEVAPLUG MMC
 Fix some SD type compatibility

 Changes in v3:
 - fix the HW_STATE (from linux mvsdio)
 - review delays and timeouts

 Changes in v2:
 - increase number of loops
 - remove initial delay

 Changes in v1:
 - review all loops, delays and timeouts
Signed-off-by: default avatarGérald Kerma <drEagle@doukki.net>
Acked-by: default avatarPantelis Antoniou <panto@antoniou-consulting.com>
parent 2591fbdb
......@@ -23,6 +23,8 @@ DECLARE_GLOBAL_DATA_PTR;
#define MVEBU_TARGET_DRAM 0
#define TIMEOUT_DELAY 5*CONFIG_SYS_HZ /* wait 5 seconds */
static void mvebu_mmc_write(u32 offs, u32 val)
{
writel(val, CONFIG_SYS_MMC_BASE + (offs));
......@@ -63,7 +65,7 @@ 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;
ulong start;
ushort waittype = 0;
ushort resptype = 0;
ushort xfertype = 0;
......@@ -72,19 +74,33 @@ 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));
/* Checking if card is busy */
while ((mvebu_mmc_read(SDIO_HW_STATE) & CARD_BUSY)) {
if (timeout == 0) {
printf("%s: card busy!\n", DRIVER_NAME);
return -1;
}
timeout--;
udelay(1000);
/*
* Hardware weirdness. The FIFO_EMPTY bit of the HW_STATE
* register is sometimes not set before a while when some
* "unusual" data block sizes are used (such as with the SWITCH
* command), even despite the fact that the XFER_DONE interrupt
* was raised. And if another data transfer starts before
* this bit comes to good sense (which eventually happens by
* itself) then the new transfer simply fails with a timeout.
*/
if (!(mvebu_mmc_read(SDIO_HW_STATE) & CMD_FIFO_EMPTY)) {
ushort hw_state, count = 0;
start = get_timer(0);
do {
hw_state = mvebu_mmc_read(SDIO_HW_STATE);
if ((get_timer(0) - start) > TIMEOUT_DELAY) {
printf("%s : FIFO_EMPTY bit missing\n",
DRIVER_NAME);
break;
}
count++;
} while (!(hw_state & CMD_FIFO_EMPTY));
debug("%s *** wait for FIFO_EMPTY bit (hw=0x%04x, count=%d, jiffies=%ld)\n",
DRIVER_NAME, hw_state, count, (get_timer(0) - (start)));
}
/* Set up for a data transfer if we have one */
......@@ -147,8 +163,7 @@ static int mvebu_mmc_send_cmd(struct mmc *mmc, struct mmc_cmd *cmd,
mvebu_mmc_write(SDIO_NOR_INTR_EN, SDIO_POLL_MASK);
mvebu_mmc_write(SDIO_ERR_INTR_EN, SDIO_POLL_MASK);
/* Waiting for completion */
timeout = 1000000;
start = get_timer(0);
while (!((mvebu_mmc_read(SDIO_NOR_INTR_STATUS)) & waittype)) {
if (mvebu_mmc_read(SDIO_NOR_INTR_STATUS) & SDIO_NOR_ERROR) {
......@@ -161,13 +176,12 @@ static int mvebu_mmc_send_cmd(struct mmc *mmc, struct mmc_cmd *cmd,
return COMM_ERR;
}
timeout--;
udelay(1);
if (timeout <= 0) {
printf("%s: command timed out\n", DRIVER_NAME);
if ((get_timer(0) - start) > TIMEOUT_DELAY) {
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;
......
......@@ -79,6 +79,7 @@
#define CMD_INHIBIT (1 << 0)
#define CMD_TXACTIVE (1 << 8)
#define CMD_RXACTIVE (1 << 9)
#define CMD_FIFO_EMPTY (1 << 13)
#define CMD_AUTOCMD12ACTIVE (1 << 14)
#define CMD_BUS_BUSY (CMD_AUTOCMD12ACTIVE | \
CMD_RXACTIVE | \
......
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