arm: add secondary cpu boot callbacks to arm_boot.c

Create two functions, write_secondary_boot() and secondary_cpu_reset_hook(),
to allow platforms more control of how secondary CPUs are brought up. The
new functions default to NULL and aren't called unless they are populated
so there are no changes to existing platform models.

Signed-off-by: Mark Langsdorf <mark.langsdorf@calxeda.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 17 insertions, 0 deletions

diff --git a/hw/arm-misc.h b/hw/arm-misc.h
index 6e8ae6b02e..5e5204bbf5 100644
--- a/hw/arm-misc.h
+++ b/hw/arm-misc.h
@@ -30,12 +30,29 @@ struct arm_boot_info {
     const char *kernel_cmdline;
     const char *initrd_filename;
     target_phys_addr_t loader_start;
+    /* multicore boards that use the default secondary core boot functions
+     * need to put the address of the secondary boot code, the boot reg,
+     * and the GIC address in the next 3 values, respectively. boards that
+     * have their own boot functions can use these values as they want.
+     */
     target_phys_addr_t smp_loader_start;
     target_phys_addr_t smp_bootreg_addr;
     target_phys_addr_t smp_priv_base;
     int nb_cpus;
     int board_id;
     int (*atag_board)(const struct arm_boot_info *info, void *p);
+    /* multicore boards that use the default secondary core boot functions
+     * can ignore these two function calls. If the default functions won't
+     * work, then write_secondary_boot() should write a suitable blob of
+     * code mimicing the secondary CPU startup process used by the board's
+     * boot loader/boot ROM code, and secondary_cpu_reset_hook() should
+     * perform any necessary CPU reset handling and set the PC for thei
+     * secondary CPUs to point at this boot blob.
+     */
+    void (*write_secondary_boot)(CPUState *env,
+                                 const struct arm_boot_info *info);
+    void (*secondary_cpu_reset_hook)(CPUState *env,
+                                     const struct arm_boot_info *info);
     /* Used internally by arm_boot.c */
     int is_linux;
     target_phys_addr_t initrd_size;