[Qemu-devel] [PATCH 2/3] PPC PReP: Use kernel entry to set nip at reset

[Fabien Chouteau]

When we load an ELF kernel we can start the board at the entry point.

Signed-off-by: Fabien Chouteau <chout...@adacore.com>
---
 hw/ppc/prep.c |   34 ++++++++++++++++++++++++++++++----
 1 file changed, 30 insertions(+), 4 deletions(-)

diff --git a/hw/ppc/prep.c b/hw/ppc/prep.c
index a2730c8..12198ff 100644
--- a/hw/ppc/prep.c
+++ b/hw/ppc/prep.c
@@ -56,6 +56,12 @@
 #define KERNEL_LOAD_ADDR 0x01000000
 #define INITRD_LOAD_ADDR 0x01800000
 
+typedef struct ResetData {
+    PowerPCCPU   *cpu;
+    bool          use_entry;
+    target_ulong  entry;        /* save kernel entry in case of reset */
+} ResetData;
+
 #if defined (HARD_DEBUG_PPC_IO) && !defined (DEBUG_PPC_IO)
 #define DEBUG_PPC_IO
 #endif
@@ -425,8 +431,13 @@ static void cpu_request_exit(void *opaque, int irq, int 
level)
 
 static void ppc_prep_reset(void *opaque)
 {
-    PowerPCCPU *cpu = opaque;
+    ResetData  *s   = (ResetData *)opaque;
+    PowerPCCPU *cpu = s->cpu;
+
 
+    if (s->use_entry) {
+        cpu->env.nip = s->entry;
+    }
     cpu_reset(CPU(cpu));
 }
 
@@ -463,11 +474,14 @@ static void ppc_prep_init(QEMUMachineInitArgs *args)
     qemu_irq *cpu_exit_irq;
     int ppc_boot_device;
     DriveInfo *hd[MAX_IDE_BUS * MAX_IDE_DEVS];
+    ResetData *reset_data;
 
     sysctrl = g_malloc0(sizeof(sysctrl_t));
 
     linux_boot = (kernel_filename != NULL);
 
+    reset_data = g_malloc0(sizeof(ResetData) * smp_cpus);
+
     /* init CPUs */
     if (cpu_model == NULL)
         cpu_model = "602";
@@ -486,7 +500,11 @@ static void ppc_prep_init(QEMUMachineInitArgs *args)
             /* Set time-base frequency to 100 Mhz */
             cpu_ppc_tb_init(env, 100UL * 1000UL * 1000UL);
         }
-        qemu_register_reset(ppc_prep_reset, cpu);
+
+        /* Reset data */
+        reset_data[i].cpu       = cpu;
+        reset_data[i].use_entry = false;
+        qemu_register_reset(ppc_prep_reset, &reset_data[i]);
     }
 
     /* allocate RAM */
@@ -521,19 +539,27 @@ static void ppc_prep_init(QEMUMachineInitArgs *args)
     }
 
     if (linux_boot) {
+        uint64_t entry;
+
         kernel_base = KERNEL_LOAD_ADDR;
 
         /* Try to load the kernel as an ELF file */
-        kernel_size = load_elf(kernel_filename, NULL, NULL, NULL, NULL, NULL,
+        kernel_size = load_elf(kernel_filename, NULL, NULL, &entry, NULL, NULL,
                                1, ELF_MACHINE, 0);
-        if (kernel_size < 0) {
+        if (kernel_size > 0) {
+            /* Entry point for CPU #0 */
+            reset_data[0].entry = entry;
+            reset_data[0].use_entry = true;
+        } else {
             /* Try to load the kernel as an binary file */
             kernel_size = load_image_targphys(kernel_filename, kernel_base,
                                               ram_size - kernel_base);
         }
+
         if (kernel_size < 0) {
             hw_error("qemu: could not load kernel '%s'\n", kernel_filename);
         }
+
         /* load initrd */
         if (initrd_filename) {
             initrd_base = INITRD_LOAD_ADDR;
-- 
1.7.9.5