Re: [Qemu-devel] [PATCH 4/4] hw/sd/omap_mmc: Reset SD card on controller reset

["Philippe Mathieu-Daudé" <f4bug@amsat.org>]

On 06/08/2018 12:44 AM, Philippe Mathieu-Daudé wrote:
> On 01/09/2018 11:01 AM, Peter Maydell wrote:
>> Since omap_mmc is still using the legacy SD card API, the SD
>> card created by sd_init() is not plugged into any bus. This
>> means that the controller has to reset it manually.
>>
>> Failing to do this mostly didn't affect the guest since the
>> guest typically does a programmed SD card reset as part of
>> its SD controller driver initialization, but would mean that
>> migration fails because it's only in sd_reset() that we
>> set up the wpgrps_size field.
>>
>> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
>> ---
>> This one isn't cc-stable because the OMAP boards don't
>> support migration at all anyway, being un-QOMified.
>> ---
>>  hw/sd/omap_mmc.c | 14 ++++++++++----
>>  1 file changed, 10 insertions(+), 4 deletions(-)
>>
>> diff --git a/hw/sd/omap_mmc.c b/hw/sd/omap_mmc.c
>> index e934cd3..5b47cad 100644
>> --- a/hw/sd/omap_mmc.c
>> +++ b/hw/sd/omap_mmc.c
>> @@ -305,6 +305,12 @@ void omap_mmc_reset(struct omap_mmc_s *host)
>>      host->cdet_enable = 0;
>>      qemu_set_irq(host->coverswitch, host->cdet_state);
>>      host->clkdiv = 0;
>> +
>> +    /* Since we're still using the legacy SD API the card is not plugged
>> +     * into any bus, and we must reset it manually. When omap_mmc is
>> +     * QOMified this must move into the QOM reset function.
>> +     */
>> +    device_reset(DEVICE(host->card));
>>  }
>>  
>>  static uint64_t omap_mmc_read(void *opaque, hwaddr offset,
>> @@ -587,8 +593,6 @@ struct omap_mmc_s *omap_mmc_init(hwaddr base,
>>      s->lines = 1;	/* TODO: needs to be settable per-board */
>>      s->rev = 1;
>>  
>> -    omap_mmc_reset(s);
>> -
>>      memory_region_init_io(&s->iomem, NULL, &omap_mmc_ops, s, "omap.mmc", 0x800);
>>      memory_region_add_subregion(sysmem, base, &s->iomem);
>>  
>> @@ -598,6 +602,8 @@ struct omap_mmc_s *omap_mmc_init(hwaddr base,
>>          exit(1);
>>      }
>>  
>> +    omap_mmc_reset(s);
>> +
>>      return s;
>>  }
>>  
>> @@ -613,8 +619,6 @@ struct omap_mmc_s *omap2_mmc_init(struct omap_target_agent_s *ta,
>>      s->lines = 4;
>>      s->rev = 2;
>>  
>> -    omap_mmc_reset(s);
>> -
>>      memory_region_init_io(&s->iomem, NULL, &omap_mmc_ops, s, "omap.mmc",
>>                            omap_l4_region_size(ta, 0));
>>      omap_l4_attach(ta, 0, &s->iomem);
>> @@ -628,6 +632,8 @@ struct omap_mmc_s *omap2_mmc_init(struct omap_target_agent_s *ta,
>>      s->cdet = qemu_allocate_irq(omap_mmc_cover_cb, s, 0);
>>      sd_set_cb(s->card, NULL, s->cdet);
>>  
>> +    omap_mmc_reset(s);
>> +
>>      return s;
>>  }
> 
> This patch broke something in the Nokia N810 tablet.

Correction, this patch is correct :)

It triggered a latent bug in omap_mmc_write(MMC_CON).

I'll submit a fix.

> 
> I used your image:
> 
> http://people.linaro.org/~peter.maydell/n8x0-images.tgz
> 
>     ecd219f7abbc17b9d9170206410355bba287831f is the first bad commit
>     commit ecd219f7abbc17b9d9170206410355bba287831f
>     Author: Peter Maydell <peter.maydell@linaro.org>
>     Date:   Tue Jan 16 13:28:13 2018 +0000
> 
>         hw/sd/omap_mmc: Reset SD card on controller reset
> 
>         Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
>         Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
>         Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> 
> Using: -append "console=ttyS1"
> 
> Before:
> 
> [    1.239471] mmci-omap mmci-omap.0: command timeout (CMD52)
> [    1.240356] mmci-omap mmci-omap.0: command timeout (CMD52)
> [    1.253967] mmci-omap mmci-omap.0: command timeout (CMD5)
> [    1.254364] mmci-omap mmci-omap.0: command timeout (CMD5)
> [    1.254730] mmci-omap mmci-omap.0: command timeout (CMD5)
> [    1.255096] mmci-omap mmci-omap.0: command timeout (CMD5)
> omap_dma4_write: Read-only register 0x000034
> omap_dma4_write: Read-only register 0x000038
> omap_dma4_write: Read-only register 0x00003c
> omap_dma4_write: Read-only register 0x000040
> omap_dma4_write: Read-only register 0x000038
> [    1.263275] mmc0: host does not support reading read-only switch.
> assuming write-enable.
> [    1.264038] mmc0: new SDHC card at address 4567
> omap_uart_read: Bad register 0x000034
> omap_uart_write: Bad register 0x000034
> omap_uart_read: Bad register 0x000034
> omap_uart_write: Bad register 0x000034
> [    1.327514] Waiting for root device /dev/mmcblk0p1...
> [    1.329925] mmcblk0: mmc0:4567 QEMU! 1.81 GiB
> [    1.333831]  mmcblk0:omap_dma4_write: Read-only register 0x000038
>  p1 p2
> [    1.425537] mmci-omap mmci-omap.0: command timeout (CMD52)
> [    1.426727] mmci-omap mmci-omap.0: command timeout (CMD52)
> omap_dma4_write: Read-only register 0x000038
> [    1.478668] mmci-omap mmci-omap.0: command timeout (CMD8)
> omap_dma4_write: Read-only register 0x000038
> omap_dma4_write: Read-only register 0x000038
> [    1.484436] mmci-omap mmci-omap.0: command timeout (CMD5)
> [    1.485015] mmci-omap mmci-omap.0: command timeout (CMD5)
> [    1.485595] mmci-omap mmci-omap.0: command timeout (CMD5)
> [    1.486022] mmci-omap mmci-omap.0: command timeout (CMD5)
> [    1.486480] mmci-omap mmci-omap.0: command timeout (CMD55)
> [    1.487030] mmci-omap mmci-omap.0: command timeout (CMD55)
> omap_dma4_write: Read-only register 0x000038
> [    1.490600] EXT3-fs (mmcblk0p1): recovery required on readonly filesystem
> [    1.491149] EXT3-fs (mmcblk0p1): write access will be enabled during
> recovery
> omap_dma4_write: Read-only register 0x000038
> [    1.498779] mmci-omap mmci-omap.0: command timeout (CMD55)
> [    1.499359] mmci-omap mmci-omap.0: command timeout (CMD55)
> [    1.499908] mmci-omap mmci-omap.0: command timeout (CMD1)
> [    1.502319] EXT3-fs: barriers not enabled
> omap_dma4_write: Read-only register 0x000038
> [    1.633636] EXT3-fs (mmcblk0p1): recovery complete
> omap_dma4_write: Read-only register 0x000034
> omap_dma4_write: Read-only register 0x000038
> omap_dma4_write: Read-only register 0x00003c
> omap_dma4_write: Read-only register 0x000040
> omap_dma4_write: Read-only register 0x000034
> omap_dma4_write: Read-only register 0x000038
> omap_dma4_write: Read-only register 0x00003c
> omap_dma4_write: Read-only register 0x000040
> omap_dma4_write: Read-only register 0x000038
> [    1.639495] kjournald starting.  Commit interval 5 seconds
> [    1.641113] EXT3-fs (mmcblk0p1): mounted filesystem with writeback
> data mode
> [    1.645233] VFS: Mounted root (ext3 filesystem) readonly on device 179:1.
> 
> After:
> 
> omap_dma4_write: Read-only register 0x000034
> omap_dma4_write: Read-only register 0x000038
> omap_dma4_write: Read-only register 0x00003c
> omap_dma4_write: Read-only register 0x000040
> omap_dma4_write: Read-only register 0x000038
> [    1.733459] mmc0: host does not support reading read-only switch.
> assuming write-enable.
> [    1.736083] mmc0: new SDHC card at address 4567
> [    1.738494] Power Management for OMAP2 initializing
> [    1.740753] PRCM revision 1.0
> omap_prcm_write: Read-only register 0x0002c8
> omap_prcm_write: Read-only register 0x0002c8
> omap_prcm_write: Read-only register 0x0002c8
> omap_prcm_read: Bad register 0x000048
> omap_prcm_write: Bad register 0x000048
> omap_prcm_read: Bad register 0x000048
> omap_prcm_write: Bad register 0x000048
> omap_prcm_read: Bad register 0x0004c8
> omap_prcm_write: Bad register 0x0004c8
> omap_prcm_write: Read-only register 0x0002c8
> omap_prcm_read: Bad register 0x0004c8
> omap_prcm_write: Bad register 0x0004c8
> omap_prcm_write: Bad register 0x000030
> [    1.744873] VFP support v0.3: implementor 41 architecture 1 part 20
> variant b rev 4
> [    1.795288] mmcblk0: mmc0:4567 QEMU! 1.81 GiB
> [    1.802581]  mmcblk0:omap_dma4_write: Read-only register 0x000038
>  p1 p2
> omap_uart_read: Bad register 0x000034
> omap_uart_write: Bad register 0x000034
> omap_uart_read: Bad register 0x000034
> omap_uart_write: Bad register 0x000034
> [    1.867645] VFS: Cannot open root device "(null)" or unknown-block(0,0)
> [    1.870056] Please append a correct "root=" boot option; here are the
> available partitions:
> [    1.874938] 1f00             128 mtdblock0 (driver?)
> [    1.877746] 1f01             384 mtdblock1 (driver?)
> [    1.880340] 1f02            2048 mtdblock2 (driver?)
> [    1.882629] 1f03            4096 mtdblock3 (driver?)
> [    1.884887] 1f04          255488 mtdblock4 (driver?)
> [    1.887207] b300         1900544 mmcblk0 driver: mmcblk
> [    1.889526]   b301         1562480 mmcblk0p1
> [    1.891723]   b302          249984 mmcblk0p2
> [    1.894165] Kernel panic - not syncing: VFS: Unable to mount root fs
> on unknown-block(0,0)
> [    1.897583] [<c002fa1c>] (unwind_backtrace+0x0/0xf0) from
> [<c02b7938>] (panic+0x5c/0xe0)
> [    1.900177] [<c02b7938>] (panic+0x5c/0xe0) from [<c0009054>]
> (mount_block_root+0x258/0x2a8)
> [    1.903137] [<c0009054>] (mount_block_root+0x258/0x2a8) from
> [<c0009268>] (prepare_namespace+0x160/0x1c4)
> [    1.909240] [<c0009268>] (prepare_namespace+0x160/0x1c4) from
> [<c0008600>] (kernel_init+0x120/0x168)
> [    1.914886] [<c0008600>] (kernel_init+0x120/0x168) from [<c002af04>]
> (kernel_thread_exit+0x0/0x8)
> omap_dma4_write: Read-only register 0x000034
> omap_dma4_write: Read-only register 0x000038
> omap_dma4_write: Read-only register 0x00003c
> omap_dma4_write: Read-only register 0x000040
> 
> Diff using -append "console=ttyS1 printk.time=0":
> 
>  mmci-omap mmci-omap.0: command timeout (CMD5)
>  mmc0: host does not support reading read-only switch. assuming
> write-enable.
>  mmc0: new SDHC card at address 4567
> -Waiting for root device /dev/mmcblk0p1...
>  mmcblk0: mmc0:4567 QEMU! 1.81 GiB
>   mmcblk0: p1 p2
> -EXT3-fs: barriers not enabled
> -EXT3-fs (mmcblk0p1): mounted filesystem with writeback data mode
> -VFS: Mounted root (ext3 filesystem) readonly on device 179:1.
> -kjournald starting.  Commit interval 5 seconds
> -devtmpfs: mounted
> -Freeing init memory: 132K
> -mmci-omap mmci-omap.0: command timeout (CMD52)
> -mmci-omap mmci-omap.0: command timeout (CMD52)
> -mmci-omap mmci-omap.0: command timeout (CMD8)
> -mmci-omap mmci-omap.0: command timeout (CMD5)
> -mmci-omap mmci-omap.0: command timeout (CMD5)
> -mmci-omap mmci-omap.0: command timeout (CMD5)
> -mmci-omap mmci-omap.0: command timeout (CMD5)
> -mmci-omap mmci-omap.0: command timeout (CMD55)
> -mmci-omap mmci-omap.0: command timeout (CMD55)
> -mmci-omap mmci-omap.0: command timeout (CMD55)
> -mmci-omap mmci-omap.0: command timeout (CMD55)
> -mmci-omap mmci-omap.0: command timeout (CMD1)
> -lcd_mipid spi1.1: performing LCD ESD recovery
> -lcd_mipid spi1.1: performing LCD ESD recovery
> +mmci-omap mmci-omap.0: command timeout (CMD18)
> +mmcblk0: retrying using single block read
> +mmci-omap mmci-omap.0: command timeout (CMD17)
> +Unable to handle kernel NULL pointer dereference at virtual address
> 00000018
> +pgd = c0004000
> +[00000018] *pgd=00000000
> +Internal error: Oops: 5 [#1] PREEMPT
> +last sysfs file:
> +Modules linked in:
> +CPU: 0    Tainted: G        W    (2.6.35~rc4-129.1-n8x0 #1)
> +PC is at mmc_omap_dma_cb+0xb8/0x174
> +LR is at omap2_dma_irq_handler+0x240/0x294
> +pc : [<c0219504>]    lr : [<c003c3ac>]    psr: 20000193
> +sp : c7d49db8  ip : c7c4c800  fp : 00000001
> +r10: 00000060  r9 : c7c4c950  r8 : 00000001
> +r7 : 0000032c  r6 : 00000007  r5 : 00000150  r4 : c7d4ba00
> +r3 : 00000000  r2 : 00000007  r1 : 00000060  r0 : 00000007
> +Flags: nzCv  IRQs off  FIQs on  Mode SVC_32  ISA ARM  Segment kernel
> +Control: 00c5387d  Table: 80004008  DAC: 00000017
> +Process mmcqd (pid: 462, stack limit = 0xc7d48268)
> +Stack: (0xc7d49db8 to 0xc7d4a000)
> +9da0:                                                       c03baed4
> 00000150
> +9dc0: 00000007 0000032c 00000001 c003c3ac 0000000c 00000000 c7d49e18
> c0399a20
> +9de0: 00000000 00000000 0000000c 00000000 c7d48000 00000001 00000001
> c0081318
> +9e00: c039ccc8 0000000c c0399a20 00000001 00000000 c00834c8 0000000c
> 00000000
> +9e20: 00000001 c002906c ffffffff fa0fe000 00000001 c0029ac8 c7d5ed24
> c7d5ed24
> +9e40: c7d49e68 00000001 c7d57320 c7d64400 00000001 c7d5ed24 c7d49e90
> c7d48000
> +9e60: 00000001 00000001 00000ffe c7d49e80 c0215fa8 c0215ffc 60000013
> ffffffff
> +9e80: 00000001 29e8d608 c7d57320 c7d49ea4 c7d49ea4 c7d49efc 00000000
> c7d49e64
> +9ea0: c0210128 00000011 00000022 00000000 00000000 00000000 00000000
> 000000b5
> +9ec0: 00000000 ffffff92 c7d49efc c7d49e90 0000000c 00000000 00000000
> 00000000
> +9ee0: 00000000 00000000 0000049d 00000000 00000000 00000000 00000000
> 05f5e100
> +9f00: 00000000 00000200 00000001 00000000 00000200 00000000 00000000
> c7d49e90
> +9f20: 00000001 c7d64800 c7eca800 c7d60980 c7d57320 c0171dc4 c7eca800
> c7d60980
> +9f40: c7d57320 00000000 000001b1 c01729a0 c7ec4e40 00000000 00000000
> c7d48000
> +9f60: c7ec4e40 00000000 c7d48000 c7ec4e40 00000000 c7d49f84 c7d57320
> c0167680
> +9f80: c7ec4e40 c7d48000 c7d5ed24 c7d5ed2c c7ec4e40 00000000 c7ec4fb0
> 00000001
> +9fa0: c7d57320 c02169b8 00000000 c7c6be28 c7d49fd4 c02168c0 c7d5ed24
> 00000000
> +9fc0: 00000000 00000000 00000000 c00692dc 00000000 00000000 c7d49fd8
> c7d49fd8
> +9fe0: 00000000 00000000 00000000 00000000 00000000 c002af04 00000000
> 00000000
> +[<c0219504>] (mmc_omap_dma_cb+0xb8/0x174) from [<c003c3ac>]
> (omap2_dma_irq_handler+0x240/0x294)
> +[<c003c3ac>] (omap2_dma_irq_handler+0x240/0x294) from [<c0081318>]
> (handle_IRQ_event+0x24/0xe4)
> +[<c0081318>] (handle_IRQ_event+0x24/0xe4) from [<c00834c8>]
> (handle_level_irq+0xd4/0x16c)
> +[<c00834c8>] (handle_level_irq+0xd4/0x16c) from [<c002906c>]
> (asm_do_IRQ+0x6c/0x8c)
> +[<c002906c>] (asm_do_IRQ+0x6c/0x8c) from [<c0029ac8>] (__irq_svc+0x48/0xac)
> +Exception stack(0xc7d49e38 to 0xc7d49e80)
> +9e20:                                                       c7d5ed24
> c7d5ed24
> +9e40: c7d49e68 00000001 c7d57320 c7d64400 00000001 c7d5ed24 c7d49e90
> c7d48000
> +9e60: 00000001 00000001 00000ffe c7d49e80 c0215fa8 c0215ffc 60000013
> ffffffff
> +[<c0029ac8>] (__irq_svc+0x48/0xac) from [<c0215ffc>]
> (mmc_blk_issue_rq+0x240/0x590)
> +[<c0215ffc>] (mmc_blk_issue_rq+0x240/0x590) from [<c02169b8>]
> (mmc_queue_thread+0xf8/0xfc)
> +[<c02169b8>] (mmc_queue_thread+0xf8/0xfc) from [<c00692dc>]
> (kthread+0x78/0x80)
> +[<c00692dc>] (kthread+0x78/0x80) from [<c002af04>]
> (kernel_thread_exit+0x0/0x8)
> +Code: e59f00c0 eafffff0 e3110020 08bd81f0 (e5931018)
> +---[ end trace 1b75b31a2719ed20 ]---
> +Kernel panic - not syncing: Fatal exception in interrupt
> 
> Trace diff:
> 
> @@ -245,6 +247,7 @@
>   16-bit register 0x000004
>   16-bit register 0x000003
>   16-bit register 0x000004
> +sdcard_reset
>   Read-only register 0x0002c8
>   Read-only register 0x0002c8
>   Read-only register 0x0002c8
> @@ -308,10 +311,6 @@
>  sdcard_response RESP#1 (normal cmd) (sz:4)
>  sdcard_app_command SD           SET_BUS_WIDTH/ACMD06 arg 0x00000002
> (state transfer)
>  sdcard_response RESP#1 (normal cmd) (sz:4)
> - Bad register 0x000034
> - Bad register 0x000034
> - Bad register 0x000034
> - Bad register 0x000034
>  sdcard_normal_command SD  READ_MULTIPLE_BLOCK/ CMD18 arg 0x00000000
> (state transfer)
>  sdcard_response RESP#1 (normal cmd) (sz:4)
>  sdcard_read_block addr 0x0 size 0x200
> @@ -325,532 +324,17 @@
>  sdcard_read_block addr 0xe00 size 0x200
>  sdcard_normal_command SD    STOP_TRANSMISSION/ CMD12 arg 0x00000000
> (state sendingdata)
>  sdcard_response RESP#1 (normal cmd) (sz:4)
> + Bad register 0x000034
> + Bad register 0x000034
> + Bad register 0x000034
> + Bad register 0x000034
>  sdcard_normal_command SD          SEND_STATUS/ CMD13 arg 0x45670000
> (state transfer)
>  sdcard_response RESP#1 (normal cmd) (sz:4)
> -sdcard_normal_command SD  READ_MULTIPLE_BLOCK/ CMD18 arg 0x00000022
> (state transfer)
> -sdcard_response RESP#1 (normal cmd) (sz:4)
> -sdcard_read_block addr 0x4400 size 0x200
> - Read-only register 0x000038
> -sdcard_read_block addr 0x4600 size 0x200
> -sdcard_normal_command SD    STOP_TRANSMISSION/ CMD12 arg 0x00000000
> (state sendingdata)
> -sdcard_response RESP#1 (normal cmd) (sz:4)
> -sdcard_normal_command SD  READ_MULTIPLE_BLOCK/ CMD18 arg 0x00000020
> (state transfer)
> -sdcard_response RESP#1 (normal cmd) (sz:4)
> -sdcard_read_block addr 0x4000 size 0x200
> ...
> 
> Regards,
> 
> Phil.
>