korg/linux
0
0
Fork 0
mirror of https://mirrors.bfsu.edu.cn/git/linux.git synced 2024-12-17 07:54:54 +08:00
Code Issues Packages Projects Releases Wiki Activity

mmc: sunxi: Mask DATA0 when updating the clock

Browse Source 
The A64 MMC controllers need DATA0 to be masked while updating the clock,
otherwise any subsequent command will result in a timeout.

It's not really clear at this point what DATA0 is exactly, but this
behaviour is present in Allwinner's tree, and has been suggested by
Allwinner engineers as fixes for the timeout.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Tested-by: Florian Vaussard <florian.vaussard@heig-vd.ch>
Acked-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This commit is contained in:
Maxime Ripard 2017-01-27 22:38:37 +01:00 committed by Ulf Hansson
parent 9a37e53e45
commit 16e821e3ba
1 changed files with 13 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

14
drivers/mmc/host/sunxi-mmc.c
View File

@ -101,6 +101,7 @@
(SDXC_SOFT_RESET | SDXC_FIFO_RESET | SDXC_DMA_RESET)
/* clock control bits */
#define SDXC_MASK_DATA0 BIT(31)
#define SDXC_CARD_CLOCK_ON BIT(16)
#define SDXC_LOW_POWER_ON BIT(17)
@ -254,6 +255,9 @@ struct sunxi_mmc_cfg {
/* does the IP block support autocalibration? */
bool can_calibrate;
/* Does DATA0 needs to be masked while the clock is updated */
bool mask_data0;
bool needs_new_timings;
};
@ -657,10 +661,12 @@ static int sunxi_mmc_oclk_onoff(struct sunxi_mmc_host *host, u32 oclk_en)
u32 rval;
rval = mmc_readl(host, REG_CLKCR);
rval &= ~(SDXC_CARD_CLOCK_ON | SDXC_LOW_POWER_ON);
rval &= ~(SDXC_CARD_CLOCK_ON | SDXC_LOW_POWER_ON | SDXC_MASK_DATA0);
if (oclk_en)
rval |= SDXC_CARD_CLOCK_ON;
if (host->cfg->mask_data0)
rval |= SDXC_MASK_DATA0;
mmc_writel(host, REG_CLKCR, rval);
@ -680,6 +686,11 @@ static int sunxi_mmc_oclk_onoff(struct sunxi_mmc_host *host, u32 oclk_en)
return -EIO;
}
if (host->cfg->mask_data0) {
rval = mmc_readl(host, REG_CLKCR);
mmc_writel(host, REG_CLKCR, rval & ~SDXC_MASK_DATA0);
}
return 0;
}
@ -1081,6 +1092,7 @@ static const struct sunxi_mmc_cfg sun50i_a64_cfg = {
.idma_des_size_bits = 16,
.clk_delays = NULL,
.can_calibrate = true,
.mask_data0 = true,
.needs_new_timings = true,
};