sun4m: pass initrd size to OpenBIOS via fw_cfg interface

This is to enable OpenBIOS to claim the initrd memory as in-use before attempting
to boot the kernel.

Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>

hw/sparc/sun4m.c

@@ -224,11 +224,12 @@ static uint64_t translate_kernel_address(void *opaque, uint64_t addr)
 
 static unsigned long sun4m_load_kernel(const char *kernel_filename,
                                        const char *initrd_filename,
-                                       ram_addr_t RAM_size)
+                                       ram_addr_t RAM_size,
+                                       uint32_t *initrd_size)
 {
     int linux_boot;
     unsigned int i;
-    long initrd_size, kernel_size;
+    long kernel_size;
     uint8_t *ptr;
 
     linux_boot = (kernel_filename != NULL);
@@ -258,23 +259,23 @@ static unsigned long sun4m_load_kernel(const char *kernel_filename,
         }
 
         /* load initrd */
-        initrd_size = 0;
+        *initrd_size = 0;
         if (initrd_filename) {
-            initrd_size = load_image_targphys(initrd_filename,
-                                              INITRD_LOAD_ADDR,
-                                              RAM_size - INITRD_LOAD_ADDR);
-            if (initrd_size < 0) {
+            *initrd_size = load_image_targphys(initrd_filename,
+                                               INITRD_LOAD_ADDR,
+                                               RAM_size - INITRD_LOAD_ADDR);
+            if ((int)*initrd_size < 0) {
                 error_report("could not load initial ram disk '%s'",
                              initrd_filename);
                 exit(1);
             }
         }
-        if (initrd_size > 0) {
+        if (*initrd_size > 0) {
             for (i = 0; i < 64 * TARGET_PAGE_SIZE; i += TARGET_PAGE_SIZE) {
                 ptr = rom_ptr(KERNEL_LOAD_ADDR + i, 24);
                 if (ptr && ldl_p(ptr) == 0x48647253) { /* HdrS */
                     stl_p(ptr + 16, INITRD_LOAD_ADDR);
-                    stl_p(ptr + 20, initrd_size);
+                    stl_p(ptr + 20, *initrd_size);
                     break;
                 }
             }
@@ -844,6 +845,7 @@ static void sun4m_hw_init(const struct sun4m_hwdef *hwdef,
     qemu_irq *cpu_irqs[MAX_CPUS], slavio_irq[32], slavio_cpu_irq[MAX_CPUS];
     qemu_irq fdc_tc;
     unsigned long kernel_size;
+    uint32_t initrd_size;
     DriveInfo *fd[MAX_FD];
     FWCfgState *fw_cfg;
     unsigned int num_vsimms;
@@ -1022,9 +1024,10 @@ static void sun4m_hw_init(const struct sun4m_hwdef *hwdef,
         empty_slot_init(hwdef->bpp_base, 0x20);
     }
 
+    initrd_size = 0;
     kernel_size = sun4m_load_kernel(machine->kernel_filename,
                                     machine->initrd_filename,
-                                    machine->ram_size);
+                                    machine->ram_size, &initrd_size);
 
     nvram_init(nvram, (uint8_t *)&nd_table[0].macaddr, machine->kernel_cmdline,
                machine->boot_order, machine->ram_size, kernel_size,
@@ -1067,7 +1070,7 @@ static void sun4m_hw_init(const struct sun4m_hwdef *hwdef,
         fw_cfg_add_i32(fw_cfg, FW_CFG_CMDLINE_SIZE, 0);
     }
     fw_cfg_add_i32(fw_cfg, FW_CFG_INITRD_ADDR, INITRD_LOAD_ADDR);
-    fw_cfg_add_i32(fw_cfg, FW_CFG_INITRD_SIZE, 0); // not used
+    fw_cfg_add_i32(fw_cfg, FW_CFG_INITRD_SIZE, initrd_size);
     fw_cfg_add_i16(fw_cfg, FW_CFG_BOOT_DEVICE, machine->boot_order[0]);
     qemu_register_boot_set(fw_cfg_boot_set, fw_cfg);
 }