summaryrefslogtreecommitdiffstats
path: root/arch/mips/kernel/relocate_kernel.S
diff options
context:
space:
mode:
Diffstat (limited to 'arch/mips/kernel/relocate_kernel.S')
-rw-r--r--arch/mips/kernel/relocate_kernel.S184
1 files changed, 184 insertions, 0 deletions
diff --git a/arch/mips/kernel/relocate_kernel.S b/arch/mips/kernel/relocate_kernel.S
new file mode 100644
index 000000000..f5b2ef979
--- /dev/null
+++ b/arch/mips/kernel/relocate_kernel.S
@@ -0,0 +1,184 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * relocate_kernel.S for kexec
+ * Created by <nschichan@corp.free.fr> on Thu Oct 12 17:49:57 2006
+ */
+
+#include <asm/asm.h>
+#include <asm/asmmacro.h>
+#include <asm/regdef.h>
+#include <asm/mipsregs.h>
+#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
+ PTR_L a2, arg2
+ PTR_L a3, arg3
+
+ PTR_L s0, kexec_indirection_page
+ PTR_L s1, kexec_start_address
+
+process_entry:
+ PTR_L s2, (s0)
+ PTR_ADDIU s0, s0, SZREG
+
+ /*
+ * In case of a kdump/crash kernel, the indirection page is not
+ * populated as the kernel is directly copied to a reserved location
+ */
+ beqz s2, done
+
+ /* destination page */
+ and s3, s2, 0x1
+ beq s3, zero, 1f
+ and s4, s2, ~0x1 /* store destination addr in s4 */
+ b process_entry
+
+1:
+ /* indirection page, update s0 */
+ and s3, s2, 0x2
+ beq s3, zero, 1f
+ and s0, s2, ~0x2
+ b process_entry
+
+1:
+ /* done page */
+ and s3, s2, 0x4
+ beq s3, zero, 1f
+ b done
+1:
+ /* source page */
+ and s3, s2, 0x8
+ beq s3, zero, process_entry
+ and s2, s2, ~0x8
+ li s6, (1 << _PAGE_SHIFT) / SZREG
+
+copy_word:
+ /* copy page word by word */
+ REG_L s5, (s2)
+ REG_S s5, (s4)
+ PTR_ADDIU s4, s4, SZREG
+ PTR_ADDIU s2, s2, SZREG
+ LONG_ADDIU s6, s6, -1
+ beq s6, zero, process_entry
+ b copy_word
+ b process_entry
+
+done:
+#ifdef CONFIG_SMP
+ /* kexec_flag reset is signal to other CPUs what kernel
+ was moved to it's location. Note - we need relocated address
+ of kexec_flag. */
+
+ bal 1f
+ 1: move t1,ra;
+ PTR_LA t2,1b
+ PTR_LA t0,kexec_flag
+ PTR_SUB t0,t0,t2;
+ PTR_ADD t0,t1,t0;
+ LONG_S zero,(t0)
+#endif
+
+#ifdef CONFIG_CPU_CAVIUM_OCTEON
+ /* We need to flush I-cache before jumping to new kernel.
+ * Unfortunately, this code is cpu-specific.
+ */
+ .set push
+ .set noreorder
+ syncw
+ syncw
+ synci 0($0)
+ .set pop
+#else
+ sync
+#endif
+ /* jump to kexec_start_address */
+ j s1
+ END(relocate_new_kernel)
+
+#ifdef CONFIG_SMP
+/*
+ * Other CPUs should wait until code is relocated and
+ * then start at entry (?) point.
+ */
+LEAF(kexec_smp_wait)
+ PTR_L a0, s_arg0
+ PTR_L a1, s_arg1
+ PTR_L a2, s_arg2
+ PTR_L a3, s_arg3
+ PTR_L s1, kexec_start_address
+
+ /* Non-relocated address works for args and kexec_start_address ( old
+ * kernel is not overwritten). But we need relocated address of
+ * kexec_flag.
+ */
+
+ bal 1f
+1: move t1,ra;
+ PTR_LA t2,1b
+ PTR_LA t0,kexec_flag
+ PTR_SUB t0,t0,t2;
+ PTR_ADD t0,t1,t0;
+
+1: LONG_L s0, (t0)
+ bne s0, zero,1b
+
+#ifdef USE_KEXEC_SMP_WAIT_FINAL
+ kexec_smp_wait_final
+#else
+ sync
+#endif
+ j s1
+ END(kexec_smp_wait)
+#endif
+
+#ifdef __mips64
+ /* all PTR's must be aligned to 8 byte in 64-bit mode */
+ .align 3
+#endif
+
+/* All parameters to new kernel are passed in registers a0-a3.
+ * kexec_args[0..3] are used to prepare register values.
+ */
+
+EXPORT(kexec_args)
+arg0: PTR_WD 0x0
+arg1: PTR_WD 0x0
+arg2: PTR_WD 0x0
+arg3: PTR_WD 0x0
+ .size kexec_args,PTRSIZE*4
+
+#ifdef CONFIG_SMP
+/*
+ * Secondary CPUs may have different kernel parameters in
+ * their registers a0-a3. secondary_kexec_args[0..3] are used
+ * to prepare register values.
+ */
+EXPORT(secondary_kexec_args)
+s_arg0: PTR_WD 0x0
+s_arg1: PTR_WD 0x0
+s_arg2: PTR_WD 0x0
+s_arg3: PTR_WD 0x0
+ .size secondary_kexec_args,PTRSIZE*4
+kexec_flag:
+ LONG 0x1
+
+#endif
+
+EXPORT(kexec_start_address)
+ PTR_WD 0x0
+ .size kexec_start_address, PTRSIZE
+
+EXPORT(kexec_indirection_page)
+ PTR_WD 0
+ .size kexec_indirection_page, PTRSIZE
+
+relocate_new_kernel_end:
+
+EXPORT(relocate_new_kernel_size)
+ PTR_WD relocate_new_kernel_end - relocate_new_kernel
+ .size relocate_new_kernel_size, PTRSIZE