Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752502Ab3IQKCS (ORCPT ); Tue, 17 Sep 2013 06:02:18 -0400 Received: from jacques.telenet-ops.be ([195.130.132.50]:53333 "EHLO jacques.telenet-ops.be" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751789Ab3IQKCP (ORCPT ); Tue, 17 Sep 2013 06:02:15 -0400 From: Geert Uytterhoeven To: linux-m68k@vger.kernel.org Cc: linux-kernel@vger.kernel.org, kexec@lists.infradead.org, Geert Uytterhoeven Subject: [PATCH 1/3] m68k: Add preliminary kexec support Date: Tue, 17 Sep 2013 12:01:31 +0200 Message-Id: <1379412095-7213-2-git-send-email-geert@linux-m68k.org> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1379412095-7213-1-git-send-email-geert@linux-m68k.org> References: <1379412095-7213-1-git-send-email-geert@linux-m68k.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 7214 Lines: 268 Signed-off-by: Geert Uytterhoeven --- arch/m68k/Kconfig | 17 ++++++++ arch/m68k/include/asm/kexec.h | 29 +++++++++++++ arch/m68k/kernel/Makefile | 2 + arch/m68k/kernel/machine_kexec.c | 71 ++++++++++++++++++++++++++++++++ arch/m68k/kernel/relocate_kernel.S | 79 ++++++++++++++++++++++++++++++++++++ include/uapi/linux/kexec.h | 1 + 6 files changed, 199 insertions(+) create mode 100644 arch/m68k/include/asm/kexec.h create mode 100644 arch/m68k/kernel/machine_kexec.c create mode 100644 arch/m68k/kernel/relocate_kernel.S diff --git a/arch/m68k/Kconfig b/arch/m68k/Kconfig index 311a300..d60497f 100644 --- a/arch/m68k/Kconfig +++ b/arch/m68k/Kconfig @@ -86,6 +86,23 @@ config MMU_SUN3 bool depends on MMU && !MMU_MOTOROLA && !MMU_COLDFIRE +config KEXEC + bool "kexec system call" + depends on MMU # FIXME + 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. + + The name comes from the similarity to the exec system call. + + It is an ongoing process to be certain the hardware in a machine + is properly shutdown, so do not be surprised if this code does not + initially work for you. As of this writing the exact hardware + interface is strongly in flux, so no good recommendation can be + made. + menu "Platform setup" source arch/m68k/Kconfig.cpu diff --git a/arch/m68k/include/asm/kexec.h b/arch/m68k/include/asm/kexec.h new file mode 100644 index 0000000..3df97ab --- /dev/null +++ b/arch/m68k/include/asm/kexec.h @@ -0,0 +1,29 @@ +#ifndef _ASM_M68K_KEXEC_H +#define _ASM_M68K_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_68K + +#ifndef __ASSEMBLY__ + +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_M68K_KEXEC_H */ diff --git a/arch/m68k/kernel/Makefile b/arch/m68k/kernel/Makefile index 655347d..7ee5f00 100644 --- a/arch/m68k/kernel/Makefile +++ b/arch/m68k/kernel/Makefile @@ -22,3 +22,5 @@ obj-$(CONFIG_PCI) += pcibios.o obj-$(CONFIG_HAS_DMA) += dma.o +obj-$(CONFIG_KEXEC) += machine_kexec.o relocate_kernel.o + diff --git a/arch/m68k/kernel/machine_kexec.c b/arch/m68k/kernel/machine_kexec.c new file mode 100644 index 0000000..c775da3 --- /dev/null +++ b/arch/m68k/kernel/machine_kexec.c @@ -0,0 +1,71 @@ +/* + * machine_kexec.c - handle transition of Linux booting another kernel + */ +#include +#include +#include +#include + +#include +#include + +extern const unsigned char relocate_new_kernel[]; +extern const size_t relocate_new_kernel_size; + +int machine_kexec_prepare(struct kimage *kimage) +{ + return 0; +} + +void machine_kexec_cleanup(struct kimage *kimage) +{ +} + +void machine_shutdown(void) +{ +} + +void machine_crash_shutdown(struct pt_regs *regs) +{ +} + +typedef void (*relocate_kernel_t)(unsigned long ptr, + unsigned long start) __noreturn; + +void machine_kexec(struct kimage *image) +{ + void *reboot_code_buffer; + unsigned long kexec_indirection_page; + + unsigned long entry; + unsigned long *ptr; + + reboot_code_buffer = page_address(image->control_code_page); + + memcpy(reboot_code_buffer, relocate_new_kernel, + relocate_new_kernel_size); + + /* + * The generic kexec code builds a page list with physical + * addresses, while we need virtual addresses + */ + for (ptr = &image->head; (entry = *ptr) && !(entry & IND_DONE); + ptr = (entry & IND_INDIRECTION) ? + phys_to_virt(entry & PAGE_MASK) : ptr + 1) { + if (*ptr & IND_SOURCE || *ptr & IND_INDIRECTION || + *ptr & IND_DESTINATION) + *ptr = (unsigned long) phys_to_virt(*ptr); + } + + kexec_indirection_page = image->head & PAGE_MASK; + + /* + * we do not want to be bothered. + */ + local_irq_disable(); + + pr_info("Will call new kernel at 0x%08lx. Bye...\n", image->start); + __flush_cache_all(); + ((relocate_kernel_t) reboot_code_buffer)(kexec_indirection_page, + image->start); +} diff --git a/arch/m68k/kernel/relocate_kernel.S b/arch/m68k/kernel/relocate_kernel.S new file mode 100644 index 0000000..8d45d9c --- /dev/null +++ b/arch/m68k/kernel/relocate_kernel.S @@ -0,0 +1,79 @@ +#include + +#include + + +.globl relocate_new_kernel + +.text +ENTRY(relocate_new_kernel) + moveq #0,%d0 + .chip 68040 /* FIXME */ + /* Disable MMU */ + /* FIXME Keep caches enabled? */ + movec %d0,%tc + movec %d0,%itt0 + movec %d0,%itt1 + movec %d0,%dtt0 + movec %d0,%dtt1 + .chip 68k + + movel 4(%sp),%a0 /* a0 = ptr */ + movel 8(%sp),%a1 /* a1 = start */ + movew #PAGE_MASK,%d2 /* d2 = PAGE_MASK */ + +1: + movel (%a0)+,%d0 /* d0 = entry = *ptr */ + jeq 5f + + btst #2,%d0 /* entry & IND_DONE? */ + jne 5f + + btst #1,%d0 /* entry & IND_INDIRECTION? */ + jeq 2f + andw %d2,%d0 + movel %d0,%a0 /* ptr = entry & PAGE_MASK */ + bra 1b + +2: + btst #0,%d0 /* entry & IND_DESTINATION? */ + jeq 3f + andw %d2,%d0 + movel %d0,%a2 /* a2 = dst = entry & PAGE_MASK */ + bra 1b + +3: + btst #3,%d0 /* entry & IND_SOURCE? */ + jeq 1b + + andw %d2,%d0 + movel %d0,%a3 /* a3 = src = entry & PAGE_MASK */ + movew #PAGE_SIZE/32 - 1,%d0 /* d0 = PAGE_SIZE/32 - 1 */ +4: + movel (%a3)+,(%a2)+ /* *dst++ = *src++ */ + movel (%a3)+,(%a2)+ /* *dst++ = *src++ */ + movel (%a3)+,(%a2)+ /* *dst++ = *src++ */ + movel (%a3)+,(%a2)+ /* *dst++ = *src++ */ + movel (%a3)+,(%a2)+ /* *dst++ = *src++ */ + movel (%a3)+,(%a2)+ /* *dst++ = *src++ */ + movel (%a3)+,(%a2)+ /* *dst++ = *src++ */ + movel (%a3)+,(%a2)+ /* *dst++ = *src++ */ + dbf %d0, 4b + bra 1b + +5: + .chip 68040 /* FIXME */ + /* Flush all caches */ + nop + cpusha %bc + nop + cinva %bc + nop + .chip 68k + + jmp (%a1) + +relocate_new_kernel_end: + +ENTRY(relocate_new_kernel_size) + .long relocate_new_kernel_end - relocate_new_kernel diff --git a/include/uapi/linux/kexec.h b/include/uapi/linux/kexec.h index 104838f..d6629d4 100644 --- a/include/uapi/linux/kexec.h +++ b/include/uapi/linux/kexec.h @@ -18,6 +18,7 @@ */ #define KEXEC_ARCH_DEFAULT ( 0 << 16) #define KEXEC_ARCH_386 ( 3 << 16) +#define KEXEC_ARCH_68K ( 4 << 16) #define KEXEC_ARCH_X86_64 (62 << 16) #define KEXEC_ARCH_PPC (20 << 16) #define KEXEC_ARCH_PPC64 (21 << 16) -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/