diff options
Diffstat (limited to 'drivers/watchdog/octeon-wdt-nmi.S')
| -rw-r--r-- | drivers/watchdog/octeon-wdt-nmi.S | 87 |
1 files changed, 87 insertions, 0 deletions
diff --git a/drivers/watchdog/octeon-wdt-nmi.S b/drivers/watchdog/octeon-wdt-nmi.S new file mode 100644 index 000000000..e308cc743 --- /dev/null +++ b/drivers/watchdog/octeon-wdt-nmi.S @@ -0,0 +1,87 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2007-2017 Cavium, Inc. + */ +#include <asm/asm.h> +#include <asm/regdef.h> + +#define CVMSEG_BASE -32768 +#define CVMSEG_SIZE 6912 +#define SAVE_REG(r) sd $r, CVMSEG_BASE + CVMSEG_SIZE - ((32 - r) * 8)($0) + + NESTED(octeon_wdt_nmi_stage2, 0, sp) + .set push + .set noreorder + .set noat + /* Clear Dcache so cvmseg works right. */ + cache 1,0($0) + /* Use K0 to do a read/modify/write of CVMMEMCTL */ + dmfc0 k0, $11, 7 + /* Clear out the size of CVMSEG */ + dins k0, $0, 0, 6 + /* Set CVMSEG to its largest value */ + ori k0, k0, 0x1c0 | 54 + /* Store the CVMMEMCTL value */ + dmtc0 k0, $11, 7 + /* + * Restore K0 from the debug scratch register, it was saved in + * the boot-vector code. + */ + dmfc0 k0, $31 + + /* + * Save all registers to the top CVMSEG. This shouldn't + * corrupt any state used by the kernel. Also all registers + * should have the value right before the NMI. + */ + SAVE_REG(0) + SAVE_REG(1) + SAVE_REG(2) + SAVE_REG(3) + SAVE_REG(4) + SAVE_REG(5) + SAVE_REG(6) + SAVE_REG(7) + SAVE_REG(8) + SAVE_REG(9) + SAVE_REG(10) + SAVE_REG(11) + SAVE_REG(12) + SAVE_REG(13) + SAVE_REG(14) + SAVE_REG(15) + SAVE_REG(16) + SAVE_REG(17) + SAVE_REG(18) + SAVE_REG(19) + SAVE_REG(20) + SAVE_REG(21) + SAVE_REG(22) + SAVE_REG(23) + SAVE_REG(24) + SAVE_REG(25) + SAVE_REG(26) + SAVE_REG(27) + SAVE_REG(28) + SAVE_REG(29) + SAVE_REG(30) + SAVE_REG(31) + /* Write zero to all CVMSEG locations per Core-15169 */ + dli a0, CVMSEG_SIZE - (33 * 8) +1: sd zero, CVMSEG_BASE(a0) + daddiu a0, a0, -8 + bgez a0, 1b + nop + /* Set the stack to begin right below the registers */ + dli sp, CVMSEG_BASE + CVMSEG_SIZE - (32 * 8) + /* Load the address of the third stage handler */ + dla $25, octeon_wdt_nmi_stage3 + /* Call the third stage handler */ + jal $25 + /* a0 is the address of the saved registers */ + move a0, sp + /* Loop forvever if we get here. */ +2: b 2b + nop + .set pop + END(octeon_wdt_nmi_stage2) |