On Fri, Apr 3, 2009 at 11:28 AM, Dipen Dudhat dipen.dudhat@freescale.com wrote:
PIO mode support for freescale eSDHC Driver. PIO has added to enable data transfer without use of eSDHC DMA Engine.
Signed-off-by: Dipen Dudhat dipen.dudhat@freescale.com
drivers/mmc/fsl_esdhc.c | 136 +++++++++++++++++++++++++++++++++++++++++++---- include/fsl_esdhc.h | 1 + 2 files changed, 127 insertions(+), 10 deletions(-)
diff --git a/drivers/mmc/fsl_esdhc.c b/drivers/mmc/fsl_esdhc.c index 0ba45cd..c96011f 100644
+#ifdef CONFIG_SYS_FSL_ESDHC_USE_PIO +static int esdhc_setup_pio_data(struct mmc *mmc, struct mmc_data *data) +{
- int timeout;
- struct fsl_esdhc *regs = mmc->priv;
- if (!(data->flags & MMC_DATA_READ)) {
- if ((in_be32(®s->prsstat) & PRSSTAT_WPSPL) == 0) {
- printf("\nThe SD card is locked. "
- "Can not write to a locked card.\n\n");
- return TIMEOUT;
- }
- out_be32(®s->dsaddr, (u32)data->src);
- } else
- out_be32(®s->dsaddr, (u32)data->dest);
Rather than create two different versions of the setup function, which are about 50% the same, make functions for the stuff above this point in each of the existing functions, and then do the #ifdef for picking which to call inside this function.
+/*
- PIO Read/Write Mode reduce the performace as DMA is not used in this mode.
- */
+static void +esdhc_pio_read_write(struct mmc *mmc, struct mmc_data *data) +{
- volatile struct fsl_esdhc *regs = mmc->priv;
- uint blocks;
- uchar* buffer;
- uint chunk_remain;
- uint databuf;
- uint size,irqstat;
- if (data->flags & MMC_DATA_READ) {
- blocks = data->blocks;
- buffer = (uchar*) data->dest;
- chunk_remain = 0;
- while(blocks) {
- size = data->blocksize;
- irqstat = in_be32(®s->irqstat);
- while(!(in_be32(®s->prsstat) & PRSSTAT_BREN));
- while(size && (!(irqstat & IRQSTAT_TC))) {
- if(chunk_remain == 0) {
- udelay(1000);
- irqstat = in_be32(®s->irqstat);
- databuf = in_be32(®s->datport);
- chunk_remain =4;
- }
- *buffer = databuf & 0xFF;
- buffer++;
- databuf >>= 8;
- size--;
- chunk_remain--;
- }
- blocks--;
- }
- } else {
- blocks = data->blocks;
- buffer = (uchar*) data->src;
- chunk_remain = 4;
- while(blocks) {
- size = data->blocksize;
- irqstat = in_be32(®s->irqstat);
- while(!(in_be32(®s->prsstat) & PRSSTAT_BWEN));
- while(size && (!(irqstat & IRQSTAT_TC))) {
- databuf >>=8;
- databuf |= (u32)*buffer<<24;
- buffer++;
- size--;
- chunk_remain--;
- if(chunk_remain == 0) {
- irqstat = in_be32(®s->irqstat);
- out_be32(®s->datport,databuf);
- chunk_remain =4;
- }
- }
- blocks--;
- }
- }
+} +#endif
Split this into a read function and a write function, and move the if() statement into the caller.
static int esdhc_setup_data(struct mmc *mmc, struct mmc_data *data) { uint wml_value; @@ -141,6 +241,23 @@ static int esdhc_setup_data(struct mmc *mmc, struct mmc_data *data) return 0; }
+static void +esdhc_dma_read_write(struct mmc *mmc)
Call this esdhc_wait_dma()
+{
- volatile struct fsl_esdhc *regs = mmc->priv;
- uint irqstat;
- do {
- irqstat = in_be32(®s->irqstat);
- if (irqstat & DATA_ERR)
- return COMM_ERR;
- if (irqstat & IRQSTAT_DTOE)
- return TIMEOUT;
- } while (!(irqstat & IRQSTAT_TC) &&
- (in_be32(®s->prsstat) & PRSSTAT_DLA));
+}
/* * Sends a command out on the bus. Takes the mmc pointer, @@ -174,7 +291,11 @@ esdhc_send_cmd(struct mmc *mmc, struct mmc_cmd *cmd, struct mmc_data *data) if (data) { int err;
+#ifdef CONFIG_SYS_FSL_ESDHC_USE_PIO
- err = esdhc_setup_pio_data(mmc, data);
+#else err = esdhc_setup_data(mmc, data); +#endif
Using my suggestion above, this would stay the same as it was.
if(err) return err; } @@ -215,16 +336,11 @@ esdhc_send_cmd(struct mmc *mmc, struct mmc_cmd *cmd, struct mmc_data *data)
/* Wait until all of the blocks are transferred */ if (data) {
- do {
- irqstat = in_be32(®s->irqstat);
- if (irqstat & DATA_ERR)
- return COMM_ERR;
- if (irqstat & IRQSTAT_DTOE)
- return TIMEOUT;
- } while (!(irqstat & IRQSTAT_TC) &&
- (in_be32(®s->prsstat) & PRSSTAT_DLA));
+#ifdef CONFIG_SYS_FSL_ESDHC_USE_PIO
- esdhc_pio_read_write(mmc,data);
My suggestion is to put the if-else from read_write here, and call the read and write functions separately.
Andy