From fc697dc0c26a5908d467454e49440862d7fe96d0 Mon Sep 17 00:00:00 2001 From: Sven Schnelle Date: Sun, 8 Sep 2019 11:33:04 +0200 Subject: parisc: add kexec syscall support Signed-off-by: Sven Schnelle Signed-off-by: Helge Deller --- arch/parisc/Kconfig | 13 +++ arch/parisc/include/asm/fixmap.h | 1 + arch/parisc/include/asm/kexec.h | 37 +++++++++ arch/parisc/kernel/Makefile | 1 + arch/parisc/kernel/kexec.c | 105 ++++++++++++++++++++++++ arch/parisc/kernel/relocate_kernel.S | 149 +++++++++++++++++++++++++++++++++++ 6 files changed, 306 insertions(+) create mode 100644 arch/parisc/include/asm/kexec.h create mode 100644 arch/parisc/kernel/kexec.c create mode 100644 arch/parisc/kernel/relocate_kernel.S (limited to 'arch/parisc') diff --git a/arch/parisc/Kconfig b/arch/parisc/Kconfig index ee59171edffe..548c767f4358 100644 --- a/arch/parisc/Kconfig +++ b/arch/parisc/Kconfig @@ -346,6 +346,19 @@ config NR_CPUS depends on SMP default "4" +config KEXEC + bool "Kexec system call" + select KEXEC_CORE + help + kexec is a system call that implements the ability to shutdown your + current kernel, and to start another kernel. It is like a reboot + but it is independent of the system firmware. And like a reboot + you can start any kernel with it, not just Linux. + + It is an ongoing process to be certain the hardware in a machine + shutdown, so do not be surprised if this code does not + initially work for you. + endmenu diff --git a/arch/parisc/include/asm/fixmap.h b/arch/parisc/include/asm/fixmap.h index 288da73d4cc0..e480b2c05407 100644 --- a/arch/parisc/include/asm/fixmap.h +++ b/arch/parisc/include/asm/fixmap.h @@ -30,6 +30,7 @@ enum fixed_addresses { /* Support writing RO kernel text via kprobes, jump labels, etc. */ FIX_TEXT_POKE0, + FIX_TEXT_KEXEC, FIX_BITMAP_COUNT }; diff --git a/arch/parisc/include/asm/kexec.h b/arch/parisc/include/asm/kexec.h new file mode 100644 index 000000000000..a99ea747d7ed --- /dev/null +++ b/arch/parisc/include/asm/kexec.h @@ -0,0 +1,37 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _ASM_PARISC_KEXEC_H +#define _ASM_PARISC_KEXEC_H + +#ifdef CONFIG_KEXEC + +/* Maximum physical address we can use pages from */ +#define KEXEC_SOURCE_MEMORY_LIMIT (-1UL) +/* Maximum address we can reach in physical address mode */ +#define KEXEC_DESTINATION_MEMORY_LIMIT (-1UL) +/* Maximum address we can use for the control code buffer */ +#define KEXEC_CONTROL_MEMORY_LIMIT (-1UL) + +#define KEXEC_CONTROL_PAGE_SIZE 4096 + +#define KEXEC_ARCH KEXEC_ARCH_PARISC +#define ARCH_HAS_KIMAGE_ARCH + +#ifndef __ASSEMBLY__ + +struct kimage_arch { + unsigned long initrd_start; + unsigned long initrd_end; + unsigned long cmdline; +}; + +static inline void crash_setup_regs(struct pt_regs *newregs, + struct pt_regs *oldregs) +{ + /* Dummy implementation for now */ +} + +#endif /* __ASSEMBLY__ */ + +#endif /* CONFIG_KEXEC */ + +#endif /* _ASM_PARISC_KEXEC_H */ diff --git a/arch/parisc/kernel/Makefile b/arch/parisc/kernel/Makefile index c232266b517c..487cf88866a8 100644 --- a/arch/parisc/kernel/Makefile +++ b/arch/parisc/kernel/Makefile @@ -37,3 +37,4 @@ obj-$(CONFIG_FUNCTION_GRAPH_TRACER) += ftrace.o obj-$(CONFIG_JUMP_LABEL) += jump_label.o obj-$(CONFIG_KGDB) += kgdb.o obj-$(CONFIG_KPROBES) += kprobes.o +obj-$(CONFIG_KEXEC) += kexec.o relocate_kernel.o diff --git a/arch/parisc/kernel/kexec.c b/arch/parisc/kernel/kexec.c new file mode 100644 index 000000000000..a92d265a2261 --- /dev/null +++ b/arch/parisc/kernel/kexec.c @@ -0,0 +1,105 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include +#include +#include +#include +#include +#include + +extern void relocate_new_kernel(unsigned long head, + unsigned long start, + unsigned long phys); + +extern const unsigned int relocate_new_kernel_size; +extern unsigned int kexec_initrd_start_offset; +extern unsigned int kexec_initrd_end_offset; +extern unsigned int kexec_cmdline_offset; +extern unsigned int kexec_free_mem_offset; + +static void kexec_show_segment_info(const struct kimage *kimage, + unsigned long n) +{ + pr_debug(" segment[%lu]: %016lx - %016lx, 0x%lx bytes, %lu pages\n", + n, + kimage->segment[n].mem, + kimage->segment[n].mem + kimage->segment[n].memsz, + (unsigned long)kimage->segment[n].memsz, + (unsigned long)kimage->segment[n].memsz / PAGE_SIZE); +} + +static void kexec_image_info(const struct kimage *kimage) +{ + unsigned long i; + + pr_debug("kexec kimage info:\n"); + pr_debug(" type: %d\n", kimage->type); + pr_debug(" start: %lx\n", kimage->start); + pr_debug(" head: %lx\n", kimage->head); + pr_debug(" nr_segments: %lu\n", kimage->nr_segments); + + for (i = 0; i < kimage->nr_segments; i++) + kexec_show_segment_info(kimage, i); +} + +void machine_kexec_cleanup(struct kimage *kimage) +{ +} + +void machine_crash_shutdown(struct pt_regs *regs) +{ +} + +void machine_shutdown(void) +{ + smp_send_stop(); + while (num_online_cpus() > 1) { + cpu_relax(); + mdelay(1); + } +} + +void machine_kexec(struct kimage *image) +{ +#ifdef CONFIG_64BIT + Elf64_Fdesc desc; +#endif + void (*reloc)(unsigned long head, + unsigned long start, + unsigned long phys); + + unsigned long phys = page_to_phys(image->control_code_page); + void *virt = (void *)__fix_to_virt(FIX_TEXT_KEXEC); + struct kimage_arch *arch = &image->arch; + + set_fixmap(FIX_TEXT_KEXEC, phys); + + flush_cache_all(); + +#ifdef CONFIG_64BIT + reloc = (void *)&desc; + desc.addr = (long long)virt; +#else + reloc = (void *)virt; +#endif + + memcpy(virt, dereference_function_descriptor(relocate_new_kernel), + relocate_new_kernel_size); + + *(unsigned long *)(virt + kexec_cmdline_offset) = arch->cmdline; + *(unsigned long *)(virt + kexec_initrd_start_offset) = arch->initrd_start; + *(unsigned long *)(virt + kexec_initrd_end_offset) = arch->initrd_end; + *(unsigned long *)(virt + kexec_free_mem_offset) = PAGE0->mem_free; + + flush_cache_all(); + flush_tlb_all(); + local_irq_disable(); + + reloc(image->head & PAGE_MASK, image->start, phys); +} + +int machine_kexec_prepare(struct kimage *image) +{ + kexec_image_info(image); + return 0; +} diff --git a/arch/parisc/kernel/relocate_kernel.S b/arch/parisc/kernel/relocate_kernel.S new file mode 100644 index 000000000000..2561e52b8d9b --- /dev/null +++ b/arch/parisc/kernel/relocate_kernel.S @@ -0,0 +1,149 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#include +#include + +#include +#include +#include +#include +#include + +.level PA_ASM_LEVEL + +.macro kexec_param name +.align 8 +ENTRY(kexec\()_\name) +#ifdef CONFIG_64BIT + .dword 0 +#else + .word 0 +#endif + +ENTRY(kexec\()_\name\()_offset) + .word kexec\()_\name - relocate_new_kernel +.endm + +.text + +/* args: + * r26 - kimage->head + * r25 - start address of kernel + * r24 - physical address of relocate code + */ + +ENTRY_CFI(relocate_new_kernel) +0: copy %arg1, %rp + /* disable I and Q bit, so we are allowed to execute RFI */ + rsm PSW_SM_I, %r0 + nop + nop + nop + nop + nop + nop + nop + + rsm PSW_SM_Q, %r0 + nop + nop + nop + nop + nop + nop + nop + + /* + * After return-from-interrupt, we want to run without Code/Data + * translation enabled just like on a normal boot. + */ + + /* calculate new physical execution address */ + ldo 1f-0b(%arg2), %r1 + mtctl %r0, %cr17 /* IIASQ */ + mtctl %r0, %cr17 /* IIASQ */ + mtctl %r1, %cr18 /* IIAOQ */ + ldo 4(%r1),%r1 + mtctl %r1, %cr18 /* IIAOQ */ +#ifdef CONFIG_64BIT + depdi,z 1, PSW_W_BIT, 1, %r1 + mtctl %r1, %cr22 /* IPSW */ +#else + mtctl %r0, %cr22 /* IPSW */ +#endif + /* lets go... */ + rfi +1: nop + nop + +.Lloop: + LDREG,ma REG_SZ(%arg0), %r3 + /* If crash kernel, no copy needed */ + cmpib,COND(=),n 0,%r3,boot + + bb,<,n %r3, 31 - IND_DONE_BIT, boot + bb,>=,n %r3, 31 - IND_INDIRECTION_BIT, .Lnotind + /* indirection, load and restart */ + movb %r3, %arg0, .Lloop + depi 0, 31, PAGE_SHIFT, %arg0 + +.Lnotind: + bb,>=,n %r3, 31 - IND_DESTINATION_BIT, .Lnotdest + b .Lloop + copy %r3, %r20 + +.Lnotdest: + bb,>= %r3, 31 - IND_SOURCE_BIT, .Lloop + depi 0, 31, PAGE_SHIFT, %r3 + copy %r3, %r21 + + /* copy page */ + copy %r0, %r18 + zdepi 1, 31 - PAGE_SHIFT, 1, %r18 + add %r20, %r18, %r17 + + depi 0, 31, PAGE_SHIFT, %r20 +.Lcopy: + copy %r20, %r12 + LDREG,ma REG_SZ(%r21), %r8 + LDREG,ma REG_SZ(%r21), %r9 + LDREG,ma REG_SZ(%r21), %r10 + LDREG,ma REG_SZ(%r21), %r11 + STREG,ma %r8, REG_SZ(%r20) + STREG,ma %r9, REG_SZ(%r20) + STREG,ma %r10, REG_SZ(%r20) + STREG,ma %r11, REG_SZ(%r20) + +#ifndef CONFIG_64BIT + LDREG,ma REG_SZ(%r21), %r8 + LDREG,ma REG_SZ(%r21), %r9 + LDREG,ma REG_SZ(%r21), %r10 + LDREG,ma REG_SZ(%r21), %r11 + STREG,ma %r8, REG_SZ(%r20) + STREG,ma %r9, REG_SZ(%r20) + STREG,ma %r10, REG_SZ(%r20) + STREG,ma %r11, REG_SZ(%r20) +#endif + + fdc %r0(%r12) + cmpb,COND(<<) %r20,%r17,.Lcopy + fic (%sr4, %r12) + b,n .Lloop + +boot: + mtctl %r0, %cr15 + + LDREG kexec_free_mem-0b(%arg2), %arg0 + LDREG kexec_cmdline-0b(%arg2), %arg1 + LDREG kexec_initrd_end-0b(%arg2), %arg3 + LDREG kexec_initrd_start-0b(%arg2), %arg2 + bv,n %r0(%rp) + +ENDPROC_CFI(relocate_new_kernel); + +ENTRY(relocate_new_kernel_size) + .word relocate_new_kernel_size - relocate_new_kernel + +kexec_param cmdline +kexec_param initrd_start +kexec_param initrd_end +kexec_param free_mem -- cgit