arm64: kexec_file: invoke the kernel without purgatory

On arm64, purgatory would do almost nothing. So just invoke secondary
kernel directly by jumping into its entry code.

While, in this case, cpu_soft_restart() must be called with dtb address
in the fifth argument, the behavior still stays compatible with kexec_load
case as long as the argument is null.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Reviewed-by: James Morse <james.morse@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

diff --git a/arch/arm64/kernel/cpu-reset.S b/arch/arm64/kernel/cpu-reset.S
index 8021b46c97431da9488003675db95f7aa24c671d..a2be30275a73c8d6efaea0dcfe475cc31ddca060 100644 (file)
--- a/arch/arm64/kernel/cpu-reset.S
+++ b/arch/arm64/kernel/cpu-reset.S
@@ -22,11 +22,11 @@
  * __cpu_soft_restart(el2_switch, entry, arg0, arg1, arg2) - Helper for
  * cpu_soft_restart.
  *
- * @el2_switch: Flag to indicate a swich to EL2 is needed.
+ * @el2_switch: Flag to indicate a switch to EL2 is needed.
  * @entry: Location to jump to for soft reset.
- * arg0: First argument passed to @entry.
- * arg1: Second argument passed to @entry.
- * arg2: Third argument passed to @entry.
+ * arg0: First argument passed to @entry. (relocation list)
+ * arg1: Second argument passed to @entry.(physical kernel entry)
+ * arg2: Third argument passed to @entry. (physical dtb address)
  *
  * Put the CPU into the same state as it would be if it had been reset, and
  * branch to what would be the reset vector. It must be executed with the

diff --git a/arch/arm64/kernel/machine_kexec.c b/arch/arm64/kernel/machine_kexec.c
index 922add8adb7498ff4609725782d09a56b46781d6..aa9c94113700e19bc1d43e23879cc8b788d75e8b 100644 (file)
--- a/arch/arm64/kernel/machine_kexec.c
+++ b/arch/arm64/kernel/machine_kexec.c
@@ -212,9 +212,17 @@ void machine_kexec(struct kimage *kimage)
         * uses physical addressing to relocate the new image to its final
         * position and transfers control to the image entry point when the
         * relocation is complete.
+        * In kexec case, kimage->start points to purgatory assuming that
+        * kernel entry and dtb address are embedded in purgatory by
+        * userspace (kexec-tools).
+        * In kexec_file case, the kernel starts directly without purgatory.
         */
-
-       cpu_soft_restart(reboot_code_buffer_phys, kimage->head, kimage->start, 0);
+       cpu_soft_restart(reboot_code_buffer_phys, kimage->head, kimage->start,
+#ifdef CONFIG_KEXEC_FILE
+                                               kimage->arch.dtb_mem);
+#else
+                                               0);
+#endif
 
        BUG(); /* Should never get here. */
 }

diff --git a/arch/arm64/kernel/relocate_kernel.S b/arch/arm64/kernel/relocate_kernel.S
index f407e422a7200b86072349cc70e1e6d5e7e1753b..95fd94209aaeb97e53ec799a62aaabaeecf7f675 100644 (file)
--- a/arch/arm64/kernel/relocate_kernel.S
+++ b/arch/arm64/kernel/relocate_kernel.S
@@ -32,6 +32,7 @@
 ENTRY(arm64_relocate_new_kernel)
 
        /* Setup the list loop variables. */
+       mov     x18, x2                         /* x18 = dtb address */
        mov     x17, x1                         /* x17 = kimage_start */
        mov     x16, x0                         /* x16 = kimage_head */
        raw_dcache_line_size x15, x0            /* x15 = dcache line size */
@@ -107,7 +108,7 @@ ENTRY(arm64_relocate_new_kernel)
        isb
 
        /* Start new image. */
-       mov     x0, xzr
+       mov     x0, x18
        mov     x1, xzr
        mov     x2, xzr
        mov     x3, xzr