SDM439平台出现部分机型SD卡不能识别mmc1: error -110 whilst initialising SD card
打印了如下的log：
1 05-10 18:01:02.699 <3>[ 3079.000640] mmc1: data txfr (0x00100000) error: -110 after 163 ms 2 05-10 18:01:02.699 <6>[ 3079.000652] sdhci: =========== REGISTER DUMP (mmc1)=========== 3 05-10 18:01:02.699 <6>[ 3079.000655] sdhci: Sys addr: 0x00000000 | Version: 0x00004d02 4 05-10 18:01:02.699 <6>[ 3079.000658] sdhci: Blk size: 0x00004040 | Blk cnt: 0x00000001 5 05-10 18:01:02.699 <6>[ 3079.000660] sdhci: Argument: 0x80ff3fff | Trn mode: 0x00000013 6 05-10 18:01:02.699 <6>[ 3079.000663] sdhci: Present: 0x03f80206 | Host ctl: 0x0000001a 7 05-10 18:01:02.699 <6>[ 3079.000665] sdhci: Power: 0x0000000d | Blk gap: 0x00000000 8 05-10 18:01:02.699 <6>[ 3079.000667] sdhci: Wake-up: 0x00000000 | Clock: 0x00000007 9 05-10 18:01:02.699 <6>[ 3079.000670] sdhci: Timeout: 0x00000001 | Int stat: 0x00000000 10 05-10 18:01:02.699 <6>[ 3079.000672] sdhci: Int enab: 0x03ff900b | Sig enab: 0x03ff100b 11 05-10 18:01:02.699 <6>[ 3079.000674] sdhci: AC12 err: 0x00000000 | Slot int: 0x00000000 12 05-10 18:01:02.699 <6>[ 3079.000677] sdhci: Caps: 0x362dc8b2 | Caps_1: 0x00008007 13 05-10 18:01:02.699 <6>[ 3079.000679] sdhci: Cmd: 0x0000063a | Max curr: 0x00000000 14 05-10 18:01:02.699 <6>[ 3079.000682] sdhci: Resp 1: 0x5b590000 | Resp 0: 0x00000900 15 05-10 18:01:02.699 <6>[ 3079.000684] sdhci: Resp 3: 0x0a404012 | Resp 2: 0x76b27f80 16 05-10 18:01:02.699 <6>[ 3079.000686] sdhci: Host ctl2: 0x00000008 17 05-10 18:01:02.699 <6>[ 3079.000689] sdhci: ADMA Err: 0x00000003 | ADMA Ptr: 0x00000000f5c9820c 18 05-10 18:01:02.699 <6>[ 3079.000695] ----------- VENDOR REGISTER DUMP ----------- 19 05-10 18:01:02.699 <6>[ 3079.000699] Data cnt: 0x00000040 | Fifo cnt: 0x00000040 | Int sts: 0x000c0000 20 05-10 18:01:02.700 <6>[ 3079.000702] DLL cfg: 0x6002642c | DLL sts: 0x00000000 | SDCC ver: 0x1000004d 21 05-10 18:01:02.700 <6>[ 3079.000705] Vndr func: 0x00018a9c | Vndr adma err : addr0: 0x000a3f80 addr1: 0x00000000 22 05-10 18:01:02.700 <6>[ 3079.000707] Vndr func2: 0xfa8018a8 23 05-10 18:01:02.700 <6>[ 3079.000746] Test bus[0 to 3]: 0x00000000 0x00000000 0x00000000 0x00000000 24 05-10 18:01:02.700 <6>[ 3079.000748] Test bus[4 to 7]: 0x00000000 0x00000000 0x00000000 0x00000000 25 05-10 18:01:02.700 <6>[ 3079.000751] Test bus[8 to 11]: 0x00000000 0x00000000 0x00000000 0x00000000 26 05-10 18:01:02.700 <6>[ 3079.000753] Test bus[12 to 15]: 0x00000000 0x00000000 0x00000000 0x00000000 27 05-10 18:01:02.700 <6>[ 3079.000755] Test bus[16 to 19]: 0x00000000 0x00000000 0x00000000 0x00000000 28 05-10 18:01:02.700 <6>[ 3079.000758] Test bus[20 to 23]: 0x00000000 0x00000000 0x00000000 0x00000000 29 05-10 18:01:02.700 <6>[ 3079.000760] Test bus[24 to 27]: 0x00000000 0x00000000 0x00000000 0x00000000 30 05-10 18:01:02.700 <6>[ 3079.000763] Test bus[28 to 31]: 0x00000000 0x00000000 0x00000000 0x00000000 31 05-10 18:01:02.700 <6>[ 3079.000766] Test bus[32 to 35]: 0x00000000 0x00000000 0x00000000 0x00000000 32 05-10 18:01:02.700 <6>[ 3079.000768] Test bus[36 to 39]: 0x00000000 0x00000000 0x00000000 0x00000000 33 05-10 18:01:02.700 <6>[ 3079.000770] Test bus[40 to 43]: 0x00000000 0x00000000 0x00000000 0x00000000 34 05-10 18:01:02.700 <6>[ 3079.000773] Test bus[44 to 47]: 0x00000000 0x00000000 0x00000000 0x00000000 35 05-10 18:01:02.700 <6>[ 3079.000776] Test bus[48 to 51]: 0x00000000 0x00000000 0x00000000 0x00000000 36 05-10 18:01:02.700 <6>[ 3079.000778] Test bus[52 to 55]: 0x00000000 0x00000000 0x00000000 0x00000000 37 05-10 18:01:02.700 <6>[ 3079.000781] Test bus[56 to 59]: 0x00000000 0x00000000 0x00000000 0x00000000 38 05-10 18:01:02.700 <6>[ 3079.000785] mmc1: clk: 400000 clk-gated: 0 claimer: kworker/7:5 pwr: 12 host->irq = 131072 39 05-10 18:01:02.700 <6>[ 3079.000788] mmc1: rpmstatus[pltfm](runtime-suspend:usage_count:disable_depth)(0:1:0) 40 05-10 18:01:02.700 <6>[ 3079.000790] sdhci: =========================================== 41 05-10 18:01:02.765 <6>[ 3079.066337] [FTS][Info]TP Ready, Device ID = 0x54 42 05-10 18:01:03.559 <3>[ 3079.862932] mmc1: mmc_sd_init_card() failure (err = -110) 43 05-10 18:01:03.559 <3>[ 3079.862944] mmc1: error -110 whilst initialising SD card
从log上分析出错的应该是在SD的初始化的阶段有问题(mmc1: error -110 whilst initialising SD card)。有可能是SD卡在上电的时候出现电源还没有稳定，需要增大上电等待的延迟,延迟的时间自己设定。代码修改如下:
1 diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c 2 index eb9ff36..7842f45 100644 3 --- a/drivers/mmc/core/core.c 4 +++ b/drivers/mmc/core/core.c 5 @@ -3313,6 +3313,9 @@ void mmc_power_up(struct mmc_host *host, u32 ocr) 6 7 host->ios.vdd = fls(ocr) - 1; 8 host->ios.power_mode = MMC_POWER_UP; 9 + 10 + printk(KERN_ERR"zhuangzebin:>>>>>%s-%d<<<<<<<\r\n",__func__,__LINE__); 11 + dev_dbg(mmc_dev(host), "zhuangzebin mmc before init\n"); 12 /* Set initial state and call mmc_set_ios */ 13 mmc_set_initial_state(host); 14 15 @@ -3328,7 +3331,7 @@ void mmc_power_up(struct mmc_host *host, u32 ocr) 16 * This delay should be sufficient to allow the power supply 17 * to reach the minimum voltage. 18 */ 19 - mmc_delay(10); 20 + mmc_delay(100); 21 22 mmc_pwrseq_post_power_on(host); 23 24 @@ -3341,9 +3344,11 @@ void mmc_power_up(struct mmc_host *host, u32 ocr) 25 * This delay must be at least 74 clock sizes, or 1 ms, or the 26 * time required to reach a stable voltage. 27 */ 28 - mmc_delay(10); 29 + mmc_delay(100); 30 31 mmc_host_clk_release(host); 32 + 33 + mmc_delay(100); 34 }
编译重新烧录固件，仍然有这个问题的存在，已经把延迟的时间增大了10倍，排除软件问题，后面找硬件分析，SD卡的一颗物料没有焊接。而且机器有拆过的痕迹，那颗物料刚好处于边缘的地方，有可能是拆卸的时候导致物料脱落，后面硬件把物料焊接上，可以识别到SD卡。