Re: [PATCH v2 1/1] arm64: dts: marvell: armada-ap806: reserve PSCI area

From: Heinrich Schuchardt
Date: Wed Dec 26 2018 - 12:10:14 EST

On 12/26/18 5:16 PM, Gregory CLEMENT wrote:
> Hi Heinrich,
>
> On ven., dÃc. 21 2018, Heinrich Schuchardt <xypron.glpk@xxxxxx> wrote:
>
>> The memory area [0x4000000-0x4200000[ is occupied by the PSCI firmware. Any
>> attempt to access it from Linux leads to an immediate crash.
>>
>> So let's make the same memory reservation as the vendor kernel.
>>
>> Signed-off-by: Heinrich Schuchardt <xypron.glpk@xxxxxx>
>
> We got a similar patch one month ago and Russell King pointed that it
> didn't match waht he saw on his MACCHIATObin:
> http://lists.infradead.org/pipermail/linux-arm-kernel/2018-November/612360.html
>
> on mine under U-Boot I got:
>
> Marvell>> md 0x4000000
> 04000000: 00000000 00000007 00000005 00000040 ............@...
> 04000010: 00000001 00001000 00000007 00000001 ................
> 04000020: 00000008 00000000 00000009 00000000 ................
> 04000030: 0000000a 00000000 ffffffff ffffffff ................
> 04000040: ffffffff ffffffff ffffffff ffffffff ................
> 04000050: ffffffff ffffffff ffffffff ffffffff ................
> 04000060: ffffffff ffffffff ffffffff ffffffff ................
> 04000070: ffffffff ffffffff ffffffff ffffffff ................
> 04000080: ffffffff ffffffff ffffffff ffffffff ................
> 04000090: ffffffff ffffffff ffffffff ffffffff ................
> 040000a0: ffffffff ffffffff ffffffff ffffffff ................
> 040000b0: ffffffff ffffffff ffffffff ffffffff ................
> 040000c0: ffffffff ffffffff ffffffff ffffffff ................
> 040000d0: ffffffff ffffffff ffffffff ffffffff ................
> 040000e0: ffffffff ffffffff ffffffff ffffffff ................
> 040000f0: ffffffff ffffffff ffffffff ffffffff ................
>
> In my case I have an old ATF, however this kind of setting should be
> done by the bootloader.
>
> I am interested by your claim about causing an immediate crash when
> accessing this region. How did you trigger it?
>
> Gregory

Hello Gregory,

judging from you U-Boot prompt you are not using mainline U-Boot. With
the legacy Marvell U-Boot I get the same output as you provide above.
But you are looking in the wrong place to confirm that this is ATF:

Marvell>> md 04017200
04017200: 616d6920 74206567 5043206f 474d2031 image to CP1 MG
04017210: 746f6e20 70757320 74726f70 000a6465 not supported..
04017220: 4f525245 20203a52 50435320 324c425f ERROR: SCP_BL2
04017230: 6f727720 6920676e 6620676d 616d726f wrong img forma
04017240: 63282074 745f336d 3d657079 0a296425 t (cm3_type=%d).
04017250: 544f4e00 3a454349 43532020 6d492050 .NOTICE: SCP Im
04017260: 20656761 73656f64 2074276e 746e6f63 age doesn't cont
04017270: 206e6961 66204d50 776d7269 0a657261 ain PM firmware.
04017280: 00000000 00000000 040144d0 00000000 .........D......
04017290: 00000001 00000019 4f525245 20203a52 ........ERROR:
040172a0: 6e695720 20776f64 203a6425 65736162 Window %d: base
040172b0: 64646120 73736572 616e7520 6e67696c address unalign
040172c0: 74206465 7830206f 000a7825 67696c41 ed to 0x%x..Alig
040172d0: 7075206e 65687420 73616220 64612065 n up the base ad
040172e0: 73657264 6f742073 25783020 000a786c dress to 0x%lx..
040172f0: 4f525245 20203a52 6e695720 20776f64 ERROR: Window

Possibly the legacy Marvell U-Boot is running at exception level 3
(EL3). This would explain why you cannot reproduce the crash with that
U-Boot.

The legacy Marvell U-Boot is in bad shape: their booti command cannot
load the initrd.img created by Debian. This is why I use mainline
U-Boot. Here you can find my recipe:

https://github.com/xypron/u-boot-build/blob/macchiatobin/Makefile (for
U-Boot v2018.11)

When I issue the md command for the region in mainline U-Boot I get a
crash:

=> md 0x4000000


04000000:"Synchronous Abort" handler, esr 0x96000210


elr: 000000000006b878 lr : 000000000006b7f4 (reloc)


elr: 000000007ff8b878 lr : 000000007ff8b7f4


x0 : 0000000000000009 x1 : 0000000000000000


x2 : 000000000000003a x3 : 0000000004000000


x4 : 0000000000000000 x5 : 000000007ffae306


x6 : 0000000000000004 x7 : 000000007fb0a1e0


x8 : 000000007fb0a0a0 x9 : 0000000000000008


x10: 00000000ffffffd0 x11: 0000000000000006


x12: 000000000001869f x13: 000000000000440c


x14: 000000007fb0a43c x15: 0000000000000008


x16: 000000007ffb49ea x17: 000000007ffb49ea


x18: 000000007fb0fdd8 x19: 0000000000000040


x20: 0000000004000000 x21: 0000000004000000


x22: 000000007ffacff1 x23: 0000000000000008


x24: 0000000000000004 x25: 0000000000000004


x26: 0000000000000004 x27: 000000007fb0a268


x28: 0000000000000000 x29: 000000007fb0a1e0



Resetting CPU ...

In Linux 4.20 without my patch I regularly experience crashes like the
one below. With the patch I never experience such a crash.

[ 683.992558] Internal error: synchronous external a
bort: 96000210 [#1] PREEMPT SMP

[ 684.000084] Modules linked in: crct10dif_ce omap_rng rng_core sg
ip_tables x_tables ipv6 sr_mod cdrom n
vme nvme_core marvell

[ 684.011369] CPU: 2 PID: 2607 Comm: dd Not tainted 4.20.0-rc7-arm64 #3

[ 684.017839] Hardware name: Marvell 8040 MACCHIATOBin (DT)

[ 684.023265] pstate: 20000005 (nzCv daif -PAN -UAO)

[ 684.028090] pc : __arch_copy_to_user+0x180/0x220

[ 684.032732] lr : copyout+0x54/0x68

[ 684.036148] sp : ffff00000d803c30

[ 684.039477] x29: ffff00000d803c30 x28: ffff800073661d98

[ 684.044815] x27: ffff8000695900d8 x26: 000000000006f09e

[ 684.050153] x25: 0000000000000000 x24: ffff00000d803d78

[ 684.055490] x23: 000000000009e000 x22: 0000000000001000

[ 684.060827] x21: ffff00000d803db0 x20: 0000000000001000

[ 684.066164] x19: ffff800004000000 x18: 0000000000000000

[ 684.071501] x17: 0fffc00000020016 x16: 0000000000000000

[ 684.076838] x15: 0000000000000000 x14: 0000000000000000

[ 684.082175] x13: 0000000000000000 x12: 0000000000000000

[ 684.087515] x11: 0000000000000000 x10: 0000000000000000

[ 684.092852] x9 : 0000000000000000 x8 : 0000000000000000

[ 684.098189] x7 : 000000000006f09e x6 : 0000ffffb58a2000

[ 684.103526] x5 : 0000ffffb58a3000 x4 : 0000000000000000

[ 684.108864] x3 : 0000ffffb58a2000 x2 : 0000000000000f80

[ 684.114201] x1 : ffff800004000000 x0 : 0000ffffb58a2000

[ 684.119540] Process dd (pid: 2607, stack limit = 0x0000000004d531a7)

[ 684.125924] Call trace:

[ 684.128385] __arch_copy_to_user+0x180/0x220

[ 684.132676] copy_page_to_iter+0xec/0x320

[ 684.136706] generic_file_read_iter+0x2ec/0x7b0

[ 684.141260] blkdev_read_iter+0x38/0x48

[ 684.145115] __vfs_read+0x110/0x148

[ 684.148620] vfs_read+0x8c/0x160

[ 684.151863] ksys_read+0x5c/0xc0

[ 684.155106] __arm64_sys_read+0x18/0x20

[ 684.158963] el0_svc_common+0x84/0xd8

[ 684.162642] el0_svc_handler+0x2c/0x80

[ 684.166410] el0_svc+0x8/0xc

[ 684.169306] Code: d503201f d503201f d503201f d503201f (a8c12027)

[ 684.175429] ---[ end trace 5fd69e42c5988a37 ]---

[ 684.180240] SError Interrupt on CPU2, code 0xbf000002 -- SError

[ 684.180242] CPU: 2 PID: 2607 Comm: dd Tainted: G D
4.20.0-rc7-arm64 #3
[ 684.180243] Hardware name: Marvell 8040 MACCHIATOBin (DT)

[ 684.180244] pstate: a0000005 (NzCv daif -PAN -UAO)

[ 684.180245] pc : unmap_page_range+0x468/0xa38

[ 684.180246] lr : unmap_page_range+0x414/0xa38

[ 684.180247] sp : ffff00000d803750

[ 684.180248] x29: ffff00000d803750 x28: ffff00000d8038f0

[ 684.180250] x27: ffff800055c6b130 x26: 0400000000000001

[ 684.180253] x25: 0000000000000000 x24: ffff7e00019b6500

[ 684.180255] x23: 0000aaaad4c27000 x22: 0000aaaad4c26000

[ 684.180257] x21: ffff00000d803838 x20: 0000aaaad4c27000

[ 684.180259] x19: 0000aaaad4c30000 x18: 0000000000000010

[ 684.180261] x17: 00000000ffffffff x16: 0000000000000000

[ 684.180263] x15: ffffffffffffffff x14: 0720072007200720

[ 684.180266] x13: 0720072007200720 x12: 0720072007200720

[ 684.180268] x11: ffff80007ffaa650 x10: 0720072007200720

[ 684.180270] x9 : 0720072007200720 x8 : ffff80007ffaa640

[ 684.180272] x7 : 0000000000000010 x6 : ffff80007ffaa640

[ 684.180274] x5 : 0000aaaad4c26000 x4 : ffff800055c7e3c0

[ 684.180276] x3 : 0000000000066d94 x2 : 0020000066d94fd3

[ 684.180278] x1 : 0000000000000009 x0 : 0000000000000009

[ 684.180281] Kernel panic - not syncing: Asynchronous SError Interrupt

[ 684.180295] SMP: stopping secondary CPUs

[ 684.180296] Kernel Offset: disabled

[ 684.180297] CPU features: 0x2,21806000

[ 684.180298] Memory Limit: none

[ 684.317162] ---[ end Kernel panic - not syncing: Asynchronous SError
Interrupt ]---

Best regards

Heinrich

>
>
>> ---
>> v2
>> Move the change from armada-8040-mcbin.dts to armada-ap806.dtsi.
>> I only have a MACCHIATObin for testing but
>> https://github.com/MarvellEmbeddedProcessors/linux-marvell
>> has the reservation in that file.
>> ---
>> arch/arm64/boot/dts/marvell/armada-ap806.dtsi | 11 +++++++++++
>> 1 file changed, 11 insertions(+)
>>
>> diff --git a/arch/arm64/boot/dts/marvell/armada-ap806.dtsi b/arch/arm64/boot/dts/marvell/armada-ap806.dtsi
>> index 7d94c1fa592a..f8dafef83db0 100644
>> --- a/arch/arm64/boot/dts/marvell/armada-ap806.dtsi
>> +++ b/arch/arm64/boot/dts/marvell/armada-ap806.dtsi
>> @@ -28,6 +28,17 @@
>> method = "smc";
>> };
>>
>> + reserved-memory {
>> + #address-cells = <2>;
>> + #size-cells = <2>;
>> + ranges;
>> +
>> + psci-area@4000000 {
>> + reg = <0x0 0x4000000 0x0 0x200000>;
>> + no-map;
>> + };
>> + };
>> +
>> ap806 {
>> #address-cells = <2>;
>> #size-cells = <2>;
>> --
>> 2.19.2
>>
>