Re: [Qemu-devel] [patch 2/2] Add Flash support to the Versatile PB platform

[Thomas Petazzoni <thomas.petazzoni@free-electrons.com>]

Le Fri, 10 Oct 2008 14:32:22 +0100,
Paul Brook <paul@codesourcery.com> a écrit :

> > Yes, makes sense. How should it behave when neither -kernel nor
> > -pflash are present ? Just display an error message and exit ?
> 
> Yes.

The following patch implements this, except that the case where neither
-kernel nor -pflash are present is already handled by vl.c:main(), so
we don't bother handling it again in the machine-specific code.

Thanks a lot for your feedback !

Thomas

---

Add Flash support to the Versatile PB platform

This patch adds the emulation of the 64 MB Intel Flash present at
address 0x34000000 on the ARM Versatile PB platform, with a 256 KB
sector size. This flash emulation is enabled using the -pflash
option.

If a -pflash option is present but no -kernel option has been
specified, Qemu starts execution at the flash starting address. If a
-kernel option has been specified together with a -pflash option, then
Qemu normally boots from the kernel (but the flash is still emulated,
of course).

The case where neither -kernel nor -pflash have been specified is
already catched by the Qemu main function :

    if (!linux_boot && net_boot == 0 &&
        !machine->nodisk_ok && nb_drives_opt == 0)
        help(1);

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
---
 hw/versatilepb.c |   43 ++++++++++++++++++++++++++++++++++++-------
 1 file changed, 36 insertions(+), 7 deletions(-)

Index: qemu/hw/versatilepb.c
===================================================================
--- qemu.orig/hw/versatilepb.c
+++ qemu/hw/versatilepb.c
@@ -15,6 +15,7 @@
 #include "sysemu.h"
 #include "pci.h"
 #include "boards.h"
+#include "flash.h"
 
 /* Primary interrupt controller.  */
 
@@ -159,6 +160,10 @@
 
 static struct arm_boot_info versatile_binfo;
 
+#define VERSATILE_FLASH_ADDR      0x34000000
+#define VERSATILE_FLASH_SIZE      (64 * 1024 * 1024)
+#define VERSATILE_FLASH_SECT_SIZE (256 * 1024)
+
 static void versatile_init(ram_addr_t ram_size, int vga_ram_size,
                      const char *boot_device, DisplayState *ds,
                      const char *kernel_filename, const char *kernel_cmdline,
@@ -174,6 +179,7 @@
     int n;
     int done_smc = 0;
     int index;
+    int hasflash = 0;
 
     if (!cpu_model)
         cpu_model = "arm926";
@@ -184,7 +190,8 @@
     }
     /* ??? RAM should repeat to fill physical memory space.  */
     /* SDRAM at address zero.  */
-    cpu_register_physical_memory(0, ram_size, IO_MEM_RAM);
+    cpu_register_physical_memory(0, ram_size,
+				 qemu_ram_alloc(ram_size) | IO_MEM_RAM);
 
     arm_sysctl_init(0x10000000, 0x41007004);
     pic = arm_pic_init_cpu(env);
@@ -249,6 +256,21 @@
     /* Add PL031 Real Time Clock. */
     pl031_init(0x101e8000,pic[10]);
 
+    index = drive_get_index(IF_PFLASH, 0, 0);
+    if (index != -1) {
+      if (!pflash_cfi01_register(VERSATILE_FLASH_ADDR,
+				 qemu_ram_alloc(VERSATILE_FLASH_SIZE),
+				 drives_table[index].bdrv,
+				 VERSATILE_FLASH_SECT_SIZE,
+				 VERSATILE_FLASH_SIZE / VERSATILE_FLASH_SECT_SIZE,
+				 4, 0, 0, 0, 0)) {
+	fprintf(stderr, "qemu: error registering flash memory.\n");
+	exit(1);
+      }
+
+      hasflash = 1;
+    }
+
     /* Memory map for Versatile/PB:  */
     /* 0x10000000 System registers.  */
     /* 0x10001000 PCI controller config registers.  */
@@ -285,12 +307,17 @@
     /*  0x101f3000 UART2.  */
     /* 0x101f4000 SSPI.  */
 
-    versatile_binfo.ram_size = ram_size;
-    versatile_binfo.kernel_filename = kernel_filename;
-    versatile_binfo.kernel_cmdline = kernel_cmdline;
-    versatile_binfo.initrd_filename = initrd_filename;
-    versatile_binfo.board_id = board_id;
-    arm_load_kernel(env, &versatile_binfo);
+    if (kernel_filename) {
+      versatile_binfo.ram_size = ram_size;
+      versatile_binfo.kernel_filename = kernel_filename;
+      versatile_binfo.kernel_cmdline = kernel_cmdline;
+      versatile_binfo.initrd_filename = initrd_filename;
+      versatile_binfo.board_id = board_id;
+      arm_load_kernel(env, &versatile_binfo);
+    }
+    else if (hasflash) {
+      env->regs[15] = VERSATILE_FLASH_ADDR;
+    }
 }
 
 static void vpb_init(ram_addr_t ram_size, int vga_ram_size,
@@ -321,6 +348,7 @@
     .init = vpb_init,
     .use_scsi = 1,
     .max_cpus = 1,
+    .ram_require = VERSATILE_FLASH_SIZE,
 };
 
 QEMUMachine versatileab_machine = {
@@ -329,4 +357,5 @@
     .init = vab_init,
     .use_scsi = 1,
     .max_cpus = 1,
+    .ram_require = VERSATILE_FLASH_SIZE,
 };


-- 
Thomas Petazzoni, Free Electrons
Kernel, drivers and embedded Linux development,
consulting, training and support.
http://free-electrons.com