From f64988f13e82dd1797e59b26c8728d26c332aa43 Mon Sep 17 00:00:00 2001 From: Aaro Koskinen Date: Sat, 28 Jun 2014 00:59:50 +0300 Subject: [PATCH] MIPS: OCTEON: watchdog: don't jump to bootloader without entry address If CONFIG_HOTPLUG_CPU is set, the driver thinks bootloader entry address is configured and we should jump there. However, this is not necessarily true if the kernel is booted on a system with older/incompatible bootloader. Add dynamic checks for the bootloader entry address. Signed-off-by: Aaro Koskinen Cc: linux-watchdog@vger.kernel.org Cc: linux-mips@linux-mips.org Cc: David Daney Cc: linux-watchdog@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/7201/ Signed-off-by: Ralf Baechle --- drivers/watchdog/octeon-wdt-main.c | 62 ++++++++++++++++-------------- 1 file changed, 34 insertions(+), 28 deletions(-) diff --git a/drivers/watchdog/octeon-wdt-main.c b/drivers/watchdog/octeon-wdt-main.c index 4baf2d788920..8453531545df 100644 --- a/drivers/watchdog/octeon-wdt-main.c +++ b/drivers/watchdog/octeon-wdt-main.c @@ -145,35 +145,39 @@ static void __init octeon_wdt_build_stage1(void) uasm_i_mfc0(&p, K0, C0_STATUS); #ifdef CONFIG_HOTPLUG_CPU - uasm_il_bbit0(&p, &r, K0, ilog2(ST0_NMI), label_enter_bootloader); + if (octeon_bootloader_entry_addr) + uasm_il_bbit0(&p, &r, K0, ilog2(ST0_NMI), + label_enter_bootloader); #endif /* Force 64-bit addressing enabled */ uasm_i_ori(&p, K0, K0, ST0_UX | ST0_SX | ST0_KX); uasm_i_mtc0(&p, K0, C0_STATUS); #ifdef CONFIG_HOTPLUG_CPU - uasm_i_mfc0(&p, K0, C0_EBASE); - /* Coreid number in K0 */ - uasm_i_andi(&p, K0, K0, 0xf); - /* 8 * coreid in bits 16-31 */ - uasm_i_dsll_safe(&p, K0, K0, 3 + 16); - uasm_i_ori(&p, K0, K0, 0x8001); - uasm_i_dsll_safe(&p, K0, K0, 16); - uasm_i_ori(&p, K0, K0, 0x0700); - uasm_i_drotr_safe(&p, K0, K0, 32); - /* - * Should result in: 0x8001,0700,0000,8*coreid which is - * CVMX_CIU_WDOGX(coreid) - 0x0500 - * - * Now ld K0, CVMX_CIU_WDOGX(coreid) - */ - uasm_i_ld(&p, K0, 0x500, K0); - /* - * If bit one set handle the NMI as a watchdog event. - * otherwise transfer control to bootloader. - */ - uasm_il_bbit0(&p, &r, K0, 1, label_enter_bootloader); - uasm_i_nop(&p); + if (octeon_bootloader_entry_addr) { + uasm_i_mfc0(&p, K0, C0_EBASE); + /* Coreid number in K0 */ + uasm_i_andi(&p, K0, K0, 0xf); + /* 8 * coreid in bits 16-31 */ + uasm_i_dsll_safe(&p, K0, K0, 3 + 16); + uasm_i_ori(&p, K0, K0, 0x8001); + uasm_i_dsll_safe(&p, K0, K0, 16); + uasm_i_ori(&p, K0, K0, 0x0700); + uasm_i_drotr_safe(&p, K0, K0, 32); + /* + * Should result in: 0x8001,0700,0000,8*coreid which is + * CVMX_CIU_WDOGX(coreid) - 0x0500 + * + * Now ld K0, CVMX_CIU_WDOGX(coreid) + */ + uasm_i_ld(&p, K0, 0x500, K0); + /* + * If bit one set handle the NMI as a watchdog event. + * otherwise transfer control to bootloader. + */ + uasm_il_bbit0(&p, &r, K0, 1, label_enter_bootloader); + uasm_i_nop(&p); + } #endif /* Clear Dcache so cvmseg works right. */ @@ -194,11 +198,13 @@ static void __init octeon_wdt_build_stage1(void) uasm_i_dmfc0(&p, K0, C0_DESAVE); #ifdef CONFIG_HOTPLUG_CPU - uasm_build_label(&l, p, label_enter_bootloader); - /* Jump to the bootloader and restore K0 */ - UASM_i_LA(&p, K0, (long)octeon_bootloader_entry_addr); - uasm_i_jr(&p, K0); - uasm_i_dmfc0(&p, K0, C0_DESAVE); + if (octeon_bootloader_entry_addr) { + uasm_build_label(&l, p, label_enter_bootloader); + /* Jump to the bootloader and restore K0 */ + UASM_i_LA(&p, K0, (long)octeon_bootloader_entry_addr); + uasm_i_jr(&p, K0); + uasm_i_dmfc0(&p, K0, C0_DESAVE); + } #endif uasm_resolve_relocs(relocs, labels); -- 2.20.1