Re: [PATCH] mips: bmips: BCM6358: disable arch_sync_dma_for_cpu_all()
From: Florian Fainelli
Date: Sat Mar 11 2023 - 12:32:36 EST
On 3/10/2023 4:13 AM, Álvaro Fernández Rojas wrote:
arch_sync_dma_for_cpu_all() causes kernel panics on BCM6358 with EHCI/OHCI:
[ 3.881739] usb 1-1: new high-speed USB device number 2 using ehci-platform
[ 3.895011] Reserved instruction in kernel code[#1]:
[ 3.900113] CPU: 0 PID: 1 Comm: init Not tainted 5.10.16 #0
[ 3.905829] $ 0 : 00000000 10008700 00000000 77d94060
[ 3.911238] $ 4 : 7fd1f088 00000000 81431cac 81431ca0
[ 3.916641] $ 8 : 00000000 ffffefff 8075cd34 00000000
[ 3.922043] $12 : 806f8d40 f3e812b7 00000000 000d9aaa
[ 3.927446] $16 : 7fd1f068 7fd1f080 7ff559b8 81428470
[ 3.932848] $20 : 00000000 00000000 55590000 77d70000
[ 3.938251] $24 : 00000018 00000010
[ 3.943655] $28 : 81430000 81431e60 81431f28 800157fc
[ 3.949058] Hi : 00000000
[ 3.952013] Lo : 00000000
[ 3.955019] epc : 80015808 setup_sigcontext+0x54/0x24c
[ 3.960464] ra : 800157fc setup_sigcontext+0x48/0x24c
[ 3.965913] Status: 10008703 KERNEL EXL IE
[ 3.970216] Cause : 00800028 (ExcCode 0a)
[ 3.974340] PrId : 0002a010 (Broadcom BMIPS4350)
[ 3.979170] Modules linked in: ohci_platform ohci_hcd fsl_mph_dr_of ehci_platform ehci_fsl ehci_hcd gpio_button_hotplug usbcore nls_base usb_common
[ 3.992907] Process init (pid: 1, threadinfo=(ptrval), task=(ptrval), tls=77e22ec8)
[ 4.000776] Stack : 81431ef4 7fd1f080 81431f28 81428470 7fd1f068 81431edc 7ff559b8 81428470
[ 4.009467] 81431f28 7fd1f080 55590000 77d70000 77d5498c 80015c70 806f0000 8063ae74
[ 4.018149] 08100002 81431f28 0000000a 08100002 81431f28 0000000a 77d6b418 00000003
[ 4.026831] ffffffff 80016414 80080734 81431ecc 81431ecc 00000001 00000000 04000000
[ 4.035512] 77d54874 00000000 00000000 00000000 00000000 00000012 00000002 00000000
[ 4.044196] ...
[ 4.046706] Call Trace:
[ 4.049238] [<80015808>] setup_sigcontext+0x54/0x24c
[ 4.054356] [<80015c70>] setup_frame+0xdc/0x124
[ 4.059015] [<80016414>] do_notify_resume+0x1dc/0x288
[ 4.064207] [<80011b50>] work_notifysig+0x10/0x18
[ 4.069036]
[ 4.070538] Code: 8fc300b4 00001025 26240008 <ac820000> ac830004 3c048063 0c0228aa 24846a00 26240010
[ 4.080686]
[ 4.082517] ---[ end trace 22a8edb41f5f983b ]---
[ 4.087374] Kernel panic - not syncing: Fatal exception
[ 4.092753] Rebooting in 1 seconds..
Did you pinpoint which specific instruction within
arch_sync_dma_for_cpu_all() is causing the reserved instruction exception?
Signed-off-by: Álvaro Fernández Rojas <noltari@xxxxxxxxx>
---
arch/mips/bmips/dma.c | 5 +++++
arch/mips/bmips/setup.c | 5 +++++
2 files changed, 10 insertions(+)
diff --git a/arch/mips/bmips/dma.c b/arch/mips/bmips/dma.c
index 33788668cbdb..3769d5efdede 100644
--- a/arch/mips/bmips/dma.c
+++ b/arch/mips/bmips/dma.c
@@ -5,11 +5,16 @@
#include <asm/bmips.h>
#include <asm/io.h>
+int bmips_dma_sync_enabled = 1;
bool bmips_dma_sync_disabled;
+
void arch_sync_dma_for_cpu_all(void)
{
void __iomem *cbr = BMIPS_GET_CBR();
u32 cfg;
+ if (!bmips_dma_sync_enabled)
+ return;
if (bmips_dma_sync_disabled)
+
if (boot_cpu_type() != CPU_BMIPS3300 &&
boot_cpu_type() != CPU_BMIPS4350 &&
boot_cpu_type() != CPU_BMIPS4380)
diff --git a/arch/mips/bmips/setup.c b/arch/mips/bmips/setup.c
index e95b3f78e7cd..825e85e14010 100644
--- a/arch/mips/bmips/setup.c
+++ b/arch/mips/bmips/setup.c
@@ -35,6 +35,8 @@
#define REG_BCM6328_OTP ((void __iomem *)CKSEG1ADDR(0x1000062c))
#define BCM6328_TP1_DISABLED BIT(9)
+extern int bmips_dma_sync_enabled;
+
static const unsigned long kbase = VMLINUX_LOAD_ADDRESS & 0xfff00000;
struct bmips_quirk {
@@ -104,6 +106,9 @@ static void bcm6358_quirks(void)
* disable SMP for now
*/
bmips_smp_enabled = 0;
+
+ /* ARCH_HAS_SYNC_DMA_FOR_CPU_ALL causes kernel panics on BCM6358 */
+ bmips_dma_sync_enabled = 0;
bmips_dma_sync_disabled = true;
}
static void bcm6368_quirks(void)
--
Florian