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-rw-r--r--drivers/mmc/sunxi_mmc.c95
1 files changed, 68 insertions, 27 deletions
diff --git a/drivers/mmc/sunxi_mmc.c b/drivers/mmc/sunxi_mmc.c
index 231f0a0..20d18d0 100644
--- a/drivers/mmc/sunxi_mmc.c
+++ b/drivers/mmc/sunxi_mmc.c
@@ -22,7 +22,6 @@ struct sunxi_mmc_host {
unsigned mmc_no;
uint32_t *mclkreg;
unsigned fatal_err;
- unsigned mod_clk;
struct sunxi_mmc *reg;
struct mmc_config cfg;
};
@@ -79,10 +78,63 @@ static int mmc_resource_init(int sdc_no)
return ret;
}
+static int mmc_set_mod_clk(struct sunxi_mmc_host *mmchost, unsigned int hz)
+{
+ unsigned int pll, pll_hz, div, n, oclk_dly, sclk_dly;
+
+ if (hz <= 24000000) {
+ pll = CCM_MMC_CTRL_OSCM24;
+ pll_hz = 24000000;
+ } else {
+ pll = CCM_MMC_CTRL_PLL6;
+ pll_hz = clock_get_pll6();
+ }
+
+ div = pll_hz / hz;
+ if (pll_hz % hz)
+ div++;
+
+ n = 0;
+ while (div > 16) {
+ n++;
+ div = (div + 1) / 2;
+ }
+
+ if (n > 3) {
+ printf("mmc %u error cannot set clock to %u\n",
+ mmchost->mmc_no, hz);
+ return -1;
+ }
+
+ /* determine delays */
+ if (hz <= 400000) {
+ oclk_dly = 0;
+ sclk_dly = 7;
+ } else if (hz <= 25000000) {
+ oclk_dly = 0;
+ sclk_dly = 5;
+ } else if (hz <= 50000000) {
+ oclk_dly = 3;
+ sclk_dly = 5;
+ } else {
+ /* hz > 50000000 */
+ oclk_dly = 2;
+ sclk_dly = 4;
+ }
+
+ writel(CCM_MMC_CTRL_ENABLE | pll | CCM_MMC_CTRL_SCLK_DLY(sclk_dly) |
+ CCM_MMC_CTRL_N(n) | CCM_MMC_CTRL_OCLK_DLY(oclk_dly) |
+ CCM_MMC_CTRL_M(div), mmchost->mclkreg);
+
+ debug("mmc %u set mod-clk req %u parent %u n %u m %u rate %u\n",
+ mmchost->mmc_no, hz, pll_hz, 1u << n, div,
+ pll_hz / (1u << n) / div);
+
+ return 0;
+}
+
static int mmc_clk_io_on(int sdc_no)
{
- unsigned int pll_clk;
- unsigned int divider;
struct sunxi_mmc_host *mmchost = &mmc_host[sdc_no];
struct sunxi_ccm_reg *ccm = (struct sunxi_ccm_reg *)SUNXI_CCM_BASE;
@@ -96,15 +148,7 @@ static int mmc_clk_io_on(int sdc_no)
setbits_le32(&ccm->ahb_reset0_cfg, 1 << AHB_RESET_OFFSET_MMC(sdc_no));
#endif
- /* config mod clock */
- pll_clk = clock_get_pll6();
- /* should be close to 100 MHz but no more, so round up */
- divider = ((pll_clk + 99999999) / 100000000) - 1;
- writel(CCM_MMC_CTRL_ENABLE | CCM_MMC_CTRL_PLL6 | divider,
- mmchost->mclkreg);
- mmchost->mod_clk = pll_clk / (divider + 1);
-
- return 0;
+ return mmc_set_mod_clk(mmchost, 24000000);
}
static int mmc_update_clk(struct mmc *mmc)
@@ -129,7 +173,7 @@ static int mmc_update_clk(struct mmc *mmc)
return 0;
}
-static int mmc_config_clock(struct mmc *mmc, unsigned div)
+static int mmc_config_clock(struct mmc *mmc)
{
struct sunxi_mmc_host *mmchost = mmc->priv;
unsigned rval = readl(&mmchost->reg->clkcr);
@@ -140,16 +184,17 @@ static int mmc_config_clock(struct mmc *mmc, unsigned div)
if (mmc_update_clk(mmc))
return -1;
- /* Change Divider Factor */
+ /* Set mod_clk to new rate */
+ if (mmc_set_mod_clk(mmchost, mmc->clock))
+ return -1;
+
+ /* Clear internal divider */
rval &= ~SUNXI_MMC_CLK_DIVIDER_MASK;
- rval |= div;
writel(rval, &mmchost->reg->clkcr);
- if (mmc_update_clk(mmc))
- return -1;
+
/* Re-enable Clock */
rval |= SUNXI_MMC_CLK_ENABLE;
writel(rval, &mmchost->reg->clkcr);
-
if (mmc_update_clk(mmc))
return -1;
@@ -159,18 +204,14 @@ static int mmc_config_clock(struct mmc *mmc, unsigned div)
static void mmc_set_ios(struct mmc *mmc)
{
struct sunxi_mmc_host *mmchost = mmc->priv;
- unsigned int clkdiv = 0;
- debug("set ios: bus_width: %x, clock: %d, mod_clk: %d\n",
- mmc->bus_width, mmc->clock, mmchost->mod_clk);
+ debug("set ios: bus_width: %x, clock: %d\n",
+ mmc->bus_width, mmc->clock);
/* Change clock first */
- clkdiv = (mmchost->mod_clk + (mmc->clock >> 1)) / mmc->clock / 2;
- if (mmc->clock) {
- if (mmc_config_clock(mmc, clkdiv)) {
- mmchost->fatal_err = 1;
- return;
- }
+ if (mmc->clock && mmc_config_clock(mmc) != 0) {
+ mmchost->fatal_err = 1;
+ return;
}
/* Change bus width */