嗨,支持者,我有两块板,一块是我的定制板,另一块是 dk2。这些板子不支持 mmc1 的高速。mmc2 进入高速并具有 50Mhz 时钟。
以下是有关 dk2 板上的 mmc1 和 mmc2 的一些信息。
- root@STM32mp1:~# cat /sys/kernel/debug/mmc0/ios
- clock: 25000000 Hz
- actual clock: 24750000 Hz
- vdd: 21 (3.3 ~ 3.4 V)
- bus mode: 2 (push-pull)
- chip select: 0 (don't care)
- power mode: 2 (on)
- bus width: 2 (4 bits)
- timing spec: 0 (legacy)
- signal voltage: 0 (3.30 V)
- driver type: 0 (driver type B)
- root@stm32mp1:~# cat /sys/kernel/debug/mmc1/ios
- clock: 50000000 Hz
- actual clock: 49500000 Hz
- vdd: 21 (3.3 ~ 3.4 V)
- bus mode: 2 (push-pull)
- chip select: 0 (don't care)
- power mode: 2 (on)
- bus width: 2 (4 bits)
- timing spec: 2 (sd high-speed)
- signal voltage: 0 (3.30 V)
- driver type: 0 (driver type B)
- root@stm32mp1:~# mount -t debugfs debugfs /mnt/
- root@stm32mp1:~# cat /mnt/^C
- root@stm32mp1:~# dmesg| grep mmc
- [ 0.000000] Kernel command line: root=/dev/mmcblk0p6 rootwait rw console=ttySTM0,115200
- [ 1.948032] mmci-pl18x 58005000.sdmmc: Linked as a consumer to regulator.8
- [ 1.953617] mmci-pl18x 58005000.sdmmc: mmc0: PL180 manf 53 rev2 at 0x58005000 irq 58,0 (pio)
- [ 1.991010] mmci-pl18x 58007000.sdmmc: allocated mmc-pwrseq
- [ 1.995496] mmci-pl18x 58007000.sdmmc: Linked as a consumer to regulator.8
- [ 2.003329] mmci-pl18x 58007000.sdmmc: mmc1: PL180 manf 53 rev1 at 0x58007000 irq 59,0 (pio)
- [ 2.042312] mmc0: host does not support reading read-only switch, assuming write-enable
- [ 2.060730] mmc0: Problem switching card into high-speed mode!
- [ 2.069832] mmc0: new SDHC card at address 0001
- [ 2.079128] mmcblk0: mmc0:0001 SD 14.6 GiB
- [ 2.094173] mmc1: queuing unknown CIS tuple 0x80 (2 bytes)
- [ 2.104142] mmc1: queuing unknown CIS tuple 0x80 (3 bytes)
- [ 2.116461] mmc1: queuing unknown CIS tuple 0x80 (3 bytes)
- [ 2.127848] mmc1: queuing unknown CIS tuple 0x80 (7 bytes)
- [ 2.136986] mmc1: queuing unknown CIS tuple 0x80 (3 bytes)
- [ 2.183527] mmc1: queuing unknown CIS tuple 0x80 (6 bytes)
- [ 2.189127] mmcblk0: p1 p2 p3 p4 p5 p6 p7
- [ 2.277342] mmc1: new high speed SDIO card at address 0001
我发现一条错误消息“mmc0:将卡切换到高速模式时出现问题!”。是什么原因导致 mmc1 没有进入速度模式?在我的应用程序中,我们需要 50Mhz 的 mmc1 以更高的 io 速度来读/写 sdcard 上的文件。