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.. This only happens when booting from TP1 instead of TP0. Signed-off-by: Álvaro Fernández Rojas <noltari@xxxxxxxxx> --- v2: check if we're running on TP1 and invert logic. arch/mips/bmips/dma.c | 5 +++++ arch/mips/bmips/setup.c | 9 +++++++++ 2 files changed, 14 insertions(+) diff --git a/arch/mips/bmips/dma.c b/arch/mips/bmips/dma.c index 33788668cbdb..2e470ef8d30f 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_disable = 0; + void arch_sync_dma_for_cpu_all(void) { void __iomem *cbr = BMIPS_GET_CBR(); u32 cfg; + if (bmips_dma_sync_disable) + return; + 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..15543e8d5b0c 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_disable; + static const unsigned long kbase = VMLINUX_LOAD_ADDRESS & 0xfff00000; struct bmips_quirk { @@ -104,6 +106,13 @@ 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 when + * booting from TP1 + */ + if (read_c0_brcm_cmt_local() & (1 << 31)) + bmips_dma_sync_disable = 1; } static void bcm6368_quirks(void) -- 2.30.2