[PATCH v4 2/5] mmc: support sdhci-pxav2.c
Philip Rakity
prakity at marvell.com
Mon Jun 13 17:35:26 EDT 2011
On Jun 8, 2011, at 2:41 AM, Zhangfei Gao wrote:
> SDHCI driver for PXAV2 SoCs, such as pxa910, the driver based on sdhci-pltfm to handle resource etc.
>
> Signed-off-by: Zhangfei Gao <zhangfei.gao at marvell.com>
> Signed-off-by: Jun Nie <njun at marvell.com>
> Signed-off-by: Qiming Wu <wuqm at marvell.com>
> ---
> +++ b/drivers/mmc/host/sdhci-pxav2.c
> +
> +#define SD_FIFO_PARAM 0xe0
> +#define DIS_PAD_SD_CLK_GATE 0x0400 /* Turn on/off Dynamic SD Clock Gating */
> +#define CLK_GATE_ON 0x0200 /* Disable/enable Clock Gate */
> +#define CLK_GATE_CTL 0x0100 /* Clock Gate Control */
> +#define CLK_GATE_SETTING_BITS (DIS_PAD_SD_CLK_GATE | \
> + CLK_GATE_ON | CLK_GATE_CTL)
> +
> +#define SD_CLOCK_BURST_SIZE_SETUP 0xe6
> +#define SDCLK_SEL_SHIFT 8
> +#define SDCLK_SEL_MASK 0x3
> +#define SDCLK_DELAY_SHIFT 10
> +#define SDCLK_DELAY_MASK 0x3c
> +
> +#define SD_CE_ATA_2 0xea
> +#define MMC_CARD 0x1000
> +#define MMC_WIDTH 0x0100
> +
> +static void pxav2_set_private_registers(struct sdhci_host *host, u8 mask)
> +{
> + struct platform_device *pdev = to_platform_device(mmc_dev(host->mmc));
> + struct sdhci_pxa_platdata *pdata = pdev->dev.platform_data;
> +
> + if (mask == SDHCI_RESET_ALL) {
> + u16 tmp = 0;
> +
> + /*
> + * tune timing of read data/command when crc error happen
> + * no performance impact
> + */
> + if (pdata->clk_delay_sel == 1) {
> + tmp = readw(host->ioaddr + SD_CLOCK_BURST_SIZE_SETUP);
> +
> + tmp &= ~(SDCLK_DELAY_MASK << SDCLK_DELAY_SHIFT);
> + tmp |= (pdata->clk_delay_cycles & SDCLK_DELAY_MASK)
> + << SDCLK_DELAY_SHIFT;
> + tmp &= ~(SDCLK_SEL_MASK << SDCLK_SEL_SHIFT);
> + tmp |= (1 & SDCLK_SEL_MASK) << SDCLK_SEL_SHIFT;
> +
> + writew(tmp, host->ioaddr + SD_CLOCK_BURST_SIZE_SETUP);
> + }
There are 3 possible value for clk_delay_sel.
0 == do not use clk_delay_cycles
1 == use programmed clk_delay_cycles value (the code above)
all other values use the sd_clk which was used to drive the output
The code about only handles 2 of the 3 cases
suggest
(if (pdata->clk_delay_sel) {
> + if (pdata->clk_delay_sel == 1) {
> + tmp = readw(host->ioaddr + SD_CLOCK_BURST_SIZE_SETUP);
> +
> + tmp &= ~(SDCLK_DELAY_MASK << SDCLK_DELAY_SHIFT);
> + tmp |= (pdata->clk_delay_cycles & SDCLK_DELAY_MASK)
> + << SDCLK_DELAY_SHIFT;
> + tmp &= ~(SDCLK_SEL_MASK << SDCLK_SEL_SHIFT);
> + tmp |= 1 << SDCLK_SEL_SHIFT;
> +
> + writew(tmp, host->ioaddr + SD_CLOCK_BURST_SIZE_SETUP);
> + } else {
> + tmp = readw(host->ioaddr + SD_CLOCK_BURST_SIZE_SETUP);
> + tmp &= ~(SDCLK_SEL_MASK << SDCLK_SEL_SHIFT);
> + tmp |= 2 << SDCLK_SEL_SHIFT;
> + writew(tmp, host->ioaddr + SD_CLOCK_BURST_SIZE_SETUP);
}
}
Philip and Mark
>
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