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authorHuacai Chen <chenhc@lemote.com>2021-04-13 16:57:23 +0800
committerThomas Bogendoerfer <tsbogend@alpha.franken.de>2021-04-16 09:18:06 +0200
commit6ce48897ce476bed86fde28752c27596e8753277 (patch)
treea04c178c9fbc4fcb2d4d81420e5a51703fa78e6c /arch/mips
parent99bca615d89510917864fac6b26fd343eff2aba2 (diff)
MIPS: Loongson64: Add kexec/kdump support
Add kexec/kdump support for Loongson64 by: 1, Provide Loongson-specific kexec functions: loongson_kexec_prepare(), loongson_kexec_shutdown() and loongson_crash_shutdown(); 2, Provide Loongson-specific assembly code in kexec_smp_wait(); To start Loongson64, The boot CPU needs 3 parameters: fw_arg0: the number of arguments in cmdline (i.e., argc). fw_arg1: structure holds cmdline such as "root=/dev/sda1 console=tty" (i.e., argv). fw_arg2: environment (i.e., envp, additional boot parameters from LEFI). Non-boot CPUs do not need one parameter as the IPI mailbox base address. They query their own IPI mailbox to get PC, SP and GP in a loopi, until the boot CPU brings them up. loongson_kexec_prepare(): Setup cmdline for kexec/kdump. The kexec/kdump cmdline comes from kexec's "append" option string. This structure will be parsed in fw_init_cmdline() of arch/mips/fw/lib/cmdline.c. Both image ->control_code_page and the cmdline need to be in a safe memory region (memory allocated by the old kernel may be corrupted by the new kernel). In order to maintain compatibility for the old firmware, the low 2MB is reserverd and safe for Loongson. So let KEXEC_CTRL_CODE and KEXEC_ARGV_ ADDR be here. LEFI parameters may be corrupted at runtime, so backup it at mips_reboot_setup(), and then restore it at loongson_kexec_shutdown() /loongson_crash_shutdown(). loongson_kexec_shutdown(): Wake up all present CPUs and let them go to reboot_code_buffer. Pass the kexec parameters to kexec_args. loongson_crash_shutdown(): Pass the kdump parameters to kexec_args. The assembly part in kexec_smp_wait provide a routine as BIOS does, in order to keep secondary CPUs in a querying loop. The layout of low 2MB memory in our design: 0x80000000, the first MB, the first 64K, Exception vectors 0x80010000, the first MB, the second 64K, STR (suspend) data 0x80020000, the first MB, the third and fourth 64K, UEFI HOB 0x80040000, the first MB, the fifth 64K, RT-Thread for SMC 0x80100000, the second MB, the first 64K, KEXEC code 0x80108000, the second MB, the second 64K, KEXEC data Cc: Eric Biederman <ebiederm@xmission.com> Tested-by: Jinyang He <hejinyang@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@kernel.org> Signed-off-by: Jinyang He <hejinyang@loongson.cn> Signed-off-by: Youling Tang <tangyouling@loongson.cn> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Diffstat (limited to 'arch/mips')
-rw-r--r--arch/mips/include/asm/mach-cavium-octeon/kernel-entry-init.h8
-rw-r--r--arch/mips/include/asm/mach-loongson64/kernel-entry-init.h27
-rw-r--r--arch/mips/kernel/relocate_kernel.S9
-rw-r--r--arch/mips/loongson64/reset.c113
4 files changed, 152 insertions, 5 deletions
diff --git a/arch/mips/include/asm/mach-cavium-octeon/kernel-entry-init.h b/arch/mips/include/asm/mach-cavium-octeon/kernel-entry-init.h
index c38b38ce5a3d..b071a7353ee1 100644
--- a/arch/mips/include/asm/mach-cavium-octeon/kernel-entry-init.h
+++ b/arch/mips/include/asm/mach-cavium-octeon/kernel-entry-init.h
@@ -157,4 +157,12 @@ octeon_main_processor:
.macro smp_slave_setup
.endm
+#define USE_KEXEC_SMP_WAIT_FINAL
+ .macro kexec_smp_wait_final
+ .set push
+ .set noreorder
+ synci 0($0)
+ .set pop
+ .endm
+
#endif /* __ASM_MACH_CAVIUM_OCTEON_KERNEL_ENTRY_H */
diff --git a/arch/mips/include/asm/mach-loongson64/kernel-entry-init.h b/arch/mips/include/asm/mach-loongson64/kernel-entry-init.h
index e4d77f4f0fe3..13373c5144f8 100644
--- a/arch/mips/include/asm/mach-loongson64/kernel-entry-init.h
+++ b/arch/mips/include/asm/mach-loongson64/kernel-entry-init.h
@@ -75,4 +75,31 @@
.set pop
.endm
+#define USE_KEXEC_SMP_WAIT_FINAL
+ .macro kexec_smp_wait_final
+ /* s0:prid s1:initfn */
+ /* a0:base t1:cpuid t2:node t9:count */
+ mfc0 t1, CP0_EBASE
+ andi t1, MIPS_EBASE_CPUNUM
+ dins a0, t1, 8, 2 /* insert core id*/
+ dext t2, t1, 2, 2
+ dins a0, t2, 44, 2 /* insert node id */
+ mfc0 s0, CP0_PRID
+ andi s0, s0, (PRID_IMP_MASK | PRID_REV_MASK)
+ beq s0, (PRID_IMP_LOONGSON_64C | PRID_REV_LOONGSON3B_R1), 1f
+ beq s0, (PRID_IMP_LOONGSON_64C | PRID_REV_LOONGSON3B_R2), 1f
+ b 2f /* Loongson-3A1000/3A2000/3A3000/3A4000 */
+1: dins a0, t2, 14, 2 /* Loongson-3B1000/3B1500 need bit 15~14 */
+2: li t9, 0x100 /* wait for init loop */
+3: addiu t9, -1 /* limit mailbox access */
+ bnez t9, 3b
+ lw s1, 0x20(a0) /* check PC as an indicator */
+ beqz s1, 2b
+ ld s1, 0x20(a0) /* get PC via mailbox reg0 */
+ ld sp, 0x28(a0) /* get SP via mailbox reg1 */
+ ld gp, 0x30(a0) /* get GP via mailbox reg2 */
+ ld a1, 0x38(a0)
+ jr s1 /* jump to initial PC */
+ .endm
+
#endif /* __ASM_MACH_LOONGSON64_KERNEL_ENTRY_H */
diff --git a/arch/mips/kernel/relocate_kernel.S b/arch/mips/kernel/relocate_kernel.S
index ac870893ba2d..f3c908abdbb8 100644
--- a/arch/mips/kernel/relocate_kernel.S
+++ b/arch/mips/kernel/relocate_kernel.S
@@ -11,6 +11,8 @@
#include <asm/stackframe.h>
#include <asm/addrspace.h>
+#include <kernel-entry-init.h>
+
LEAF(relocate_new_kernel)
PTR_L a0, arg0
PTR_L a1, arg1
@@ -125,11 +127,8 @@ LEAF(kexec_smp_wait)
1: LONG_L s0, (t0)
bne s0, zero,1b
-#ifdef CONFIG_CPU_CAVIUM_OCTEON
- .set push
- .set noreorder
- synci 0($0)
- .set pop
+#ifdef USE_KEXEC_SMP_WAIT_FINAL
+ kexec_smp_wait_final
#else
sync
#endif
diff --git a/arch/mips/loongson64/reset.c b/arch/mips/loongson64/reset.c
index 3bb8a1ed9348..c97bfdc8c922 100644
--- a/arch/mips/loongson64/reset.c
+++ b/arch/mips/loongson64/reset.c
@@ -6,9 +6,14 @@
* Copyright (C) 2009 Lemote, Inc.
* Author: Zhangjin Wu, wuzhangjin@gmail.com
*/
+#include <linux/cpu.h>
+#include <linux/delay.h>
#include <linux/init.h>
+#include <linux/kexec.h>
#include <linux/pm.h>
+#include <linux/slab.h>
+#include <asm/bootinfo.h>
#include <asm/idle.h>
#include <asm/reboot.h>
@@ -47,12 +52,120 @@ static void loongson_halt(void)
}
}
+#ifdef CONFIG_KEXEC
+
+/* 0X80000000~0X80200000 is safe */
+#define MAX_ARGS 64
+#define KEXEC_CTRL_CODE 0xFFFFFFFF80100000UL
+#define KEXEC_ARGV_ADDR 0xFFFFFFFF80108000UL
+#define KEXEC_ARGV_SIZE COMMAND_LINE_SIZE
+#define KEXEC_ENVP_SIZE 4800
+
+static int kexec_argc;
+static int kdump_argc;
+static void *kexec_argv;
+static void *kdump_argv;
+static void *kexec_envp;
+
+static int loongson_kexec_prepare(struct kimage *image)
+{
+ int i, argc = 0;
+ unsigned int *argv;
+ char *str, *ptr, *bootloader = "kexec";
+
+ /* argv at offset 0, argv[] at offset KEXEC_ARGV_SIZE/2 */
+ if (image->type == KEXEC_TYPE_DEFAULT)
+ argv = (unsigned int *)kexec_argv;
+ else
+ argv = (unsigned int *)kdump_argv;
+
+ argv[argc++] = (unsigned int)(KEXEC_ARGV_ADDR + KEXEC_ARGV_SIZE/2);
+
+ for (i = 0; i < image->nr_segments; i++) {
+ if (!strncmp(bootloader, (char *)image->segment[i].buf,
+ strlen(bootloader))) {
+ /*
+ * convert command line string to array
+ * of parameters (as bootloader does).
+ */
+ int offt;
+ str = (char *)argv + KEXEC_ARGV_SIZE/2;
+ memcpy(str, image->segment[i].buf, KEXEC_ARGV_SIZE/2);
+ ptr = strchr(str, ' ');
+
+ while (ptr && (argc < MAX_ARGS)) {
+ *ptr = '\0';
+ if (ptr[1] != ' ') {
+ offt = (int)(ptr - str + 1);
+ argv[argc] = KEXEC_ARGV_ADDR + KEXEC_ARGV_SIZE/2 + offt;
+ argc++;
+ }
+ ptr = strchr(ptr + 1, ' ');
+ }
+ break;
+ }
+ }
+
+ if (image->type == KEXEC_TYPE_DEFAULT)
+ kexec_argc = argc;
+ else
+ kdump_argc = argc;
+
+ /* kexec/kdump need a safe page to save reboot_code_buffer */
+ image->control_code_page = virt_to_page((void *)KEXEC_CTRL_CODE);
+
+ return 0;
+}
+
+static void loongson_kexec_shutdown(void)
+{
+#ifdef CONFIG_SMP
+ int cpu;
+
+ /* All CPUs go to reboot_code_buffer */
+ for_each_possible_cpu(cpu)
+ if (!cpu_online(cpu))
+ cpu_device_up(get_cpu_device(cpu));
+#endif
+ kexec_args[0] = kexec_argc;
+ kexec_args[1] = fw_arg1;
+ kexec_args[2] = fw_arg2;
+ secondary_kexec_args[0] = TO_UNCAC(0x3ff01000);
+ memcpy((void *)fw_arg1, kexec_argv, KEXEC_ARGV_SIZE);
+ memcpy((void *)fw_arg2, kexec_envp, KEXEC_ENVP_SIZE);
+}
+
+static void loongson_crash_shutdown(struct pt_regs *regs)
+{
+ default_machine_crash_shutdown(regs);
+ kexec_args[0] = kdump_argc;
+ kexec_args[1] = fw_arg1;
+ kexec_args[2] = fw_arg2;
+ secondary_kexec_args[0] = TO_UNCAC(0x3ff01000);
+ memcpy((void *)fw_arg1, kdump_argv, KEXEC_ARGV_SIZE);
+ memcpy((void *)fw_arg2, kexec_envp, KEXEC_ENVP_SIZE);
+}
+
+#endif
+
static int __init mips_reboot_setup(void)
{
_machine_restart = loongson_restart;
_machine_halt = loongson_halt;
pm_power_off = loongson_poweroff;
+#ifdef CONFIG_KEXEC
+ kexec_argv = kmalloc(KEXEC_ARGV_SIZE, GFP_KERNEL);
+ kdump_argv = kmalloc(KEXEC_ARGV_SIZE, GFP_KERNEL);
+ kexec_envp = kmalloc(KEXEC_ENVP_SIZE, GFP_KERNEL);
+ fw_arg1 = KEXEC_ARGV_ADDR;
+ memcpy(kexec_envp, (void *)fw_arg2, KEXEC_ENVP_SIZE);
+
+ _machine_kexec_prepare = loongson_kexec_prepare;
+ _machine_kexec_shutdown = loongson_kexec_shutdown;
+ _machine_crash_shutdown = loongson_crash_shutdown;
+#endif
+
return 0;
}

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