mount rootfs fails unless rootdelay=1 added about linux-sunxi HOT 2 OPEN

yes, the SD driver takes around a second to react, I use rootwait myself.

from linux-sunxi.

I modified the mmc driver (drivers/mmc/sunxi-host/host_op.c) so that the initial timer function which detects the presence of an sd card runs immediately instead of with the default delay of 1 second.

changing where the timer is defined within sunximmc_probe to:

smc_host->cd_timer.expires = jiffies;

This does work, I was able to boot my system without the rootwait argument passed to the kernel, though, perhaps (as this is essentially a race) I was just lucky.

However, this then causes some warnings on boot (tested on mele A1000)

[ 2.990000] [mmc_pm]: no sdio card used in configuration
[ 3.000000] [mmc]: sunximmc_init
[ 3.010000] [mmc]: sunxi mmc controller using config : 0xb
[ 3.020000] [mmc]: sunxi-mmc.0: pdev->name: sunxi-mmc, pdev->id: 0
[ 3.030000] [mmc]: mmc 0 power off !!
[ 3.030000] [mmc]: mmc0 Probe: base:0xdc8de000 irq:32 dma:0 pdes:0xd9a6c000, ret 0.
[ 3.050000] [mmc]: mmc 0 detect change, present 1
[ 3.060000] [mmc]: mmc 0 power on !!
[ 3.060000] [mmc]: sunxi-mmc.1: pdev->name: sunxi-mmc, pdev->id: 1
[ 3.070000] [mmc]: mmc 1 power off !!
[ 3.080000] [mmc]: mmc1 Probe: base:0xdc8e0000 irq:33 dma:0 pdes:0xd9a74000, ret 0.
[ 3.090000] [mmc]: sunxi-mmc.3: pdev->name: sunxi-mmc, pdev->id: 3
[ 3.110000] [mmc]: mmc 3 power off !!
[ 3.110000] [mmc]: sdxc_request_done(L1113): smc 0 err, cmd 52, RTO !!
[ 3.120000] [mmc]: mmc3 Probe: base:0xdc8e2000 irq:35 dma:0 pdes:0xd9a78000, ret 0.
[ 3.140000] [mmc]: sdxc_request_done(L1113): smc 0 err, cmd 52, RTO !!
[ 3.160000] [mmc]: sdxc_request_done(L1113): smc 0 err, cmd 5, RTO !!
[ 3.180000] [mmc]: sdxc_request_done(L1113): smc 0 err, cmd 5, RTO !!
[ 3.200000] [mmc]: sdxc_request_done(L1113): smc 0 err, cmd 5, RTO !!
[ 3.220000] [mmc]: sdxc_request_done(L1113): smc 0 err, cmd 5, RTO !!

Looking into drivers/mmc/sunxi-host/sdxc.c the RTO message indicates that there was a Response Timeout.

Based on the series of timeouts (possibly because we're still probing other (not used?) ports) I think that specifying the rootwait kernel argument is the right option for the moment.

from linux-sunxi.