于 2020年9月15日 GMT+08:00 下午9:07:43, Jinyang He <hejinyang@xxxxxxxxxxx> 写到: >Add loongson_kexec_prepare(), loongson_kexec_shutdown() and >loongson_kexec_crashdown() for passing the parameters of kexec_args. > >To start loongson64, CPU0 needs 3 parameters: >fw_arg0: the number of cmd. >fw_arg1: cmd structure which seems strange, the cmd array[index]'s > value is cmd string's address, index >= 1. >fw_arg2: environment. > >Secondary CPUs do not need parameter at once. They query their >mailbox to get PC, SP and GP in a loop before CPU0 brings them up >and passes these parameters via mailbox. > >loongson_kexec_prepare(): Alloc new memory to save cmd for kexec. >Combine the kexec append option string as cmd structure, and the cmd >struct will be parsed in fw_init_cmdline() of arch/mips/fw/lib/cmdline.c. >image->control_code_page need pointing to a safe memory page. In order to >maintain compatibility for the old firmware the low 2MB is reserverd >and safe for Loongson. So let it points here. > >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 provide a way like BIOS doing to keep secondary >CPUs in a querying loop. > >This patch referenced [1][2][3]. > >[1] arch/mips/cavium-octeon/setup.c >[2] https://patchwork.kernel.org/patch/10799217/ >[3] https://gitee.com/loongsonlab/qemu/blob/master/hw/mips/loongson3a_rom.h > >Co-developed-by: Youling Tang <tangyouling@xxxxxxxxxxx> >Signed-off-by: Youling Tang <tangyouling@xxxxxxxxxxx> >Signed-off-by: Jinyang He <hejinyang@xxxxxxxxxxx> >--- > arch/mips/kernel/relocate_kernel.S | 19 ++++++++ > arch/mips/loongson64/reset.c | 88 ++++++++++++++++++++++++++++++++++++++ > 2 files changed, 107 insertions(+) > >diff --git a/arch/mips/kernel/relocate_kernel.S b/arch/mips/kernel/relocate_kernel.S >index ac87089..061cbfb 100644 >--- a/arch/mips/kernel/relocate_kernel.S >+++ b/arch/mips/kernel/relocate_kernel.S >@@ -133,6 +133,25 @@ LEAF(kexec_smp_wait) > #else > sync > #endif >+ >+#ifdef CONFIG_CPU_LOONGSON64 >+#define MAILBOX_BASE 0x900000003ff01000 Please avoid hardcoded SMP information. You're breaking Loongson 3B support. Thank. - Jiaxun >+ mfc0 t1, CP0_EBASE >+ andi t1, MIPS_EBASE_CPUNUM >+ dli t0, MAILBOX_BASE >+ andi t3, t1, 0x3 >+ sll t3, 8 >+ or t0, t0, t3 /* insert core id */ >+ andi t2, t1, 0xc >+ dsll t2, 42 >+ or t0, t0, t2 /* insert node id */ >+1: ld s1, 0x20(t0) /* get PC via mailbox0 */ >+ beqz s1, 1b >+ ld sp, 0x28(t0) /* get SP via mailbox1 */ >+ ld gp, 0x30(t0) /* get GP via mailbox2 */ >+ ld a1, 0x38(t0) >+ jr s1 >+#endif > j s1 > END(kexec_smp_wait) > #endif >diff --git a/arch/mips/loongson64/reset.c b/arch/mips/loongson64/reset.c >index 3bb8a1e..322c326 100644 >--- a/arch/mips/loongson64/reset.c >+++ b/arch/mips/loongson64/reset.c >@@ -47,12 +47,100 @@ static void loongson_halt(void) > } > } > >+#ifdef CONFIG_KEXEC >+#include <linux/cpu.h> >+#include <linux/kexec.h> >+ >+#include <asm/bootinfo.h> >+ >+#define CONTROL_CODE_PAGE 0xFFFFFFFF80000000UL >+static int kexec_argc; >+static int kdump_argc; >+static void *kexec_argv; >+static void *kdump_argv; >+ >+static int loongson_kexec_prepare(struct kimage *image) >+{ >+ int i, offt, argc = 0; >+ int *argv; >+ char *str, *ptr, *bootloader = "kexec"; >+ >+ argv = kmalloc(COMMAND_LINE_SIZE, GFP_KERNEL); >+ if (!argv) >+ return -ENOMEM; >+ >+ for (i = 0; i < image->nr_segments; i++) { >+ if (!strncmp(bootloader, (char *)image->segment[i].buf, >+ strlen(bootloader))) { >+ argv[argc++] = fw_arg1 + COMMAND_LINE_SIZE/2; >+ str = (char *)argv + COMMAND_LINE_SIZE/2; >+ memcpy(str, image->segment[i].buf, COMMAND_LINE_SIZE/2); >+ ptr = strchr(str, ' '); >+ while (ptr) { >+ *ptr = '\0'; >+ if (ptr[1] != ' ') { >+ offt = (int)(ptr - str + 1); >+ argv[argc++] = fw_arg1 + COMMAND_LINE_SIZE/2 + offt; >+ } >+ ptr = strchr(ptr + 1, ' '); >+ } >+ break; >+ } >+ } >+ >+ /* Kexec/kdump needs a safe page to save reboot_code_buffer. */ >+ image->control_code_page = virt_to_page((void *)CONTROL_CODE_PAGE); >+ >+ if (image->type == KEXEC_TYPE_CRASH) { >+ kfree(kdump_argv); >+ kdump_argc = argc; >+ kdump_argv = argv; >+ } else { >+ kfree(kexec_argv); >+ kexec_argc = argc; >+ kexec_argv = argv; >+ } >+ >+ return 0; >+} >+ >+static void loongson_kexec_shutdown(void) >+{ >+#ifdef CONFIG_SMP >+ bringup_nonboot_cpus(loongson_sysconf.nr_cpus); >+#endif >+ fw_arg0 = kexec_argc; >+ memcpy((void *)fw_arg1, kexec_argv, COMMAND_LINE_SIZE); >+ >+ kexec_args[0] = fw_arg0; >+ kexec_args[1] = fw_arg1; >+ kexec_args[2] = fw_arg2; >+} >+ >+static void loongson_crash_shutdown(struct pt_regs *regs) >+{ >+ default_machine_crash_shutdown(regs); >+ fw_arg0 = kdump_argc; >+ memcpy((void *)fw_arg1, kdump_argv, COMMAND_LINE_SIZE); >+ >+ kexec_args[0] = fw_arg0; >+ kexec_args[1] = fw_arg1; >+ kexec_args[2] = fw_arg2; >+} >+#endif >+ > static int __init mips_reboot_setup(void) > { > _machine_restart = loongson_restart; > _machine_halt = loongson_halt; > pm_power_off = loongson_poweroff; > >+#ifdef CONFIG_KEXEC >+ _machine_kexec_prepare = loongson_kexec_prepare; >+ _machine_kexec_shutdown = loongson_kexec_shutdown; >+ _machine_crash_shutdown = loongson_crash_shutdown; >+#endif >+ > return 0; > } > _______________________________________________ kexec mailing list kexec@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/kexec
