[Qemu-devel] [patch 0/2] Add flash emulation to the ARM Versatile PB platform

[Qemu-devel] [patch 0/2] Add flash emulation to the ARM Versatile PB platform

[Thomas Petazzoni]

Hi,

The following two patches add flash emulation to the ARM Versatile PB
platform. Compared to the previous version of the patchset sent on
October, 2nd, this version has the following changes :

 - Drop the two patches that have been included in SVN ;

 - In the write buffer increase patch, instead of changing the type of
   cmd from uint8_t to uint16_t, directly use value to set
   pfl->counter, since value is not 8 bits masked. Suggested by
   Andrzej Zaborowski ;

 - Change the memory reservation scheme for the Versatile
   platform. Instead of hardcoding the RAM size, we use the
   .ram_require machine argument to reserve memory for the flash, and
   allow the user to define a custom RAM size using the -m
   option. Hopefully, this adresses Paul Brook's comment about this
   patch.

Thanks !

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

[Qemu-devel] [patch 1/2] Increase write buffer size in pflash emulation

[Thomas Petazzoni]

[-- Attachment #1: pflash-cfi01-increase-write-buffer-size --]
[-- Type: text/plain, Size: 1705 bytes --]

The current flash emulation code advertises a write buffer size of 16
bytes (1 << 4, according to offset 0x2A of the CFI table). This is
very small compared to normal write buffer sizes, and makes the
process of writing to the flash very slow (at least from U-Boot).

This patch increases this size to 2048 bytes. Except the modification
of the CFI table, the only other required modification is to use
"value" instead of "cmd" to set pfl->counter, because cmd is truncated
to the 8 lower bits of value, while the number of bytes for a write
can now be greater than 255 bytes.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
---
 hw/pflash_cfi01.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

Index: qemu/hw/pflash_cfi01.c
===================================================================
--- qemu.orig/hw/pflash_cfi01.c
+++ qemu/hw/pflash_cfi01.c
@@ -276,8 +276,8 @@
 
             break;
         case 0xe8:
-            DPRINTF("%s: block write of %x bytes\n", __func__, cmd);
-            pfl->counter = cmd;
+            DPRINTF("%s: block write of %x bytes\n", __func__, value);
+            pfl->counter = value;
             pfl->wcycle++;
             break;
         case 0x60:
@@ -583,7 +583,7 @@
     pfl->cfi_table[0x28] = 0x02;
     pfl->cfi_table[0x29] = 0x00;
     /* Max number of bytes in multi-bytes write */
-    pfl->cfi_table[0x2A] = 0x04;
+    pfl->cfi_table[0x2A] = 0x0B;
     pfl->cfi_table[0x2B] = 0x00;
     /* Number of erase block regions (uniform) */
     pfl->cfi_table[0x2C] = 0x01;

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

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

[Thomas Petazzoni]

[-- Attachment #1: versatilepb-add-flash-support --]
[-- Type: text/plain, Size: 3659 bytes --]

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 not enabled, Qemu falls back to the traditionnal way of
loading the kernel.

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 (! hasflash) {
+      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 {
+      env->regs[15] = 0x34000000;
+    }
 }
 
 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

Re: [Qemu-devel] [patch 0/2] Add flash emulation to the ARM Versatile PB platform

[Aurelien Jarno]

On Fri, Oct 10, 2008 at 10:36:02AM +0200, Thomas Petazzoni wrote:
> Hi,
> 
> The following two patches add flash emulation to the ARM Versatile PB
> platform. Compared to the previous version of the patchset sent on
> October, 2nd, this version has the following changes :

I suppose that if you propose such a change, you are using the flash
with a bootloader in it. Could you please give us more details about it?

-- 
  .''`.  Aurelien Jarno	            | GPG: 1024D/F1BCDB73
 : :' :  Debian developer           | Electrical Engineer
 `. `'   aurel32@debian.org         | aurelien@aurel32.net
   `-    people.debian.org/~aurel32 | www.aurel32.net

Re: [Qemu-devel] [patch 0/2] Add flash emulation to the ARM Versatile PB platform

[Thomas Petazzoni]

Le Fri, 10 Oct 2008 11:01:23 +0200,
Aurelien Jarno <aurelien@aurel32.net> a écrit :

> I suppose that if you propose such a change, you are using the flash
> with a bootloader in it. Could you please give us more details about
> it?

Sure. With these patches in place, I'm able to boot U-Boot in Qemu, use
TFTP to load a kernel, flash it, and boot it. I've detailed what I've
done at http://thomas.enix.org/Blog-20081002153859-Technologie.

It works pretty well, except that I add to hack the CFG_HZ and timer
configuration values in U-Boot to get some same network timeout values
and such. Any help in this area would be appreciated.

If you want more details, I'll be glad to give them.

Sincerly,

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

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

[Paul Brook]

> +    if (! hasflash) {
> +      versatile_binfo.ram_size = ram_size;

This should be dependent on the presence of the -kernel option, not the 
absence of flash.

Paul

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

[Thomas Petazzoni]

Le Fri, 10 Oct 2008 14:02:17 +0100,
Paul Brook <paul@codesourcery.com> a écrit :

> > +    if (! hasflash) {
> > +      versatile_binfo.ram_size = ram_size;
> 
> This should be dependent on the presence of the -kernel option, not
> the absence of flash.

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

Thanks a lot for your feedback,

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

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

[Paul Brook]

On Friday 10 October 2008, Thomas Petazzoni wrote:
> Le Fri, 10 Oct 2008 14:02:17 +0100,
>
> Paul Brook <paul@codesourcery.com> a écrit :
> > > +    if (! hasflash) {
> > > +      versatile_binfo.ram_size = ram_size;
> >
> > This should be dependent on the presence of the -kernel option, not
> > the absence of flash.
>
> Yes, makes sense. How should it behave when neither -kernel nor -pflash
> are present ? Just display an error message and exit ?

Yes.

Paul

Re: [Qemu-devel] [patch 0/2] Add flash emulation to the ARM Versatile PB platform

[Jean-Christophe PLAGNIOL-VILLARD]

On 11:48 Fri 10 Oct     , Thomas Petazzoni wrote:
> Le Fri, 10 Oct 2008 11:01:23 +0200,
> Aurelien Jarno <aurelien@aurel32.net> a écrit :
> 
> > I suppose that if you propose such a change, you are using the flash
> > with a bootloader in it. Could you please give us more details about
> > it?
> 
> Sure. With these patches in place, I'm able to boot U-Boot in Qemu, use
> TFTP to load a kernel, flash it, and boot it. I've detailed what I've
> done at http://thomas.enix.org/Blog-20081002153859-Technologie.
> 
> It works pretty well, except that I add to hack the CFG_HZ and timer
> configuration values in U-Boot to get some same network timeout values
> and such. Any help in this area would be appreciated.
> 
> If you want more details, I'll be glad to give them.
I think I'll nice to add u-boot ML too and the ARM maintainer in copy maybe

Best Regards,
J.

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

[Thomas Petazzoni]

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

[Qemu-devel] [PATCH] Update documentation

[Thomas Petazzoni]

Le Fri, 10 Oct 2008 10:36:02 +0200,
Thomas Petazzoni <thomas.petazzoni@free-electrons.com> a écrit :

> The following two patches add flash emulation to the ARM Versatile PB
> platform. Compared to the previous version of the patchset sent on
> October, 2nd, this version has the following changes :

Another patch, which updates the documentation concerning flash
emulation in the ARM Versatile platform.

If you want me to resend the complete patchset properly, just ask.

Sincerly,

Thomas

---

Mention flash emulation in Versatile documentation

In the Qemu documentation, mention the fact the flash emulation is
available for the Versatile platform.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
---
 qemu-doc.texi |    2 ++
 1 file changed, 2 insertions(+)

Index: qemu/qemu-doc.texi
===================================================================
--- qemu.orig/qemu-doc.texi
+++ qemu/qemu-doc.texi
@@ -2528,6 +2528,8 @@
 @item
 PL190 Vectored Interrupt Controller
 @item
+Intel-compatible Flash memory (64 megabytes)
+@item
 Four PL011 UARTs
 @item
 SMC 91c111 Ethernet adapter


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

Re: [Qemu-devel] [patch 0/2] Add flash emulation to the ARM Versatile PB platform

[Thomas Petazzoni]

Le Fri, 10 Oct 2008 16:02:52 +0200,
Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com> a écrit :

> > > I suppose that if you propose such a change, you are using the
> > > flash with a bootloader in it. Could you please give us more
> > > details about it?
> > 
> > Sure. With these patches in place, I'm able to boot U-Boot in Qemu,
> > use TFTP to load a kernel, flash it, and boot it. I've detailed
> > what I've done at
> > http://thomas.enix.org/Blog-20081002153859-Technologie.
> > 
> > It works pretty well, except that I add to hack the CFG_HZ and timer
> > configuration values in U-Boot to get some same network timeout
> > values and such. Any help in this area would be appreciated.
> > 
> > If you want more details, I'll be glad to give them.
> I think I'll nice to add u-boot ML too and the ARM maintainer in copy
> maybe

Yes, maybe I should contact the U-Boot people. To get U-Boot to work on
the Versatile PB platform, I had to make several modifications to the
U-Boot configuration :

 * Switch to a custom versatile flash driver to the generic CFI driver.
   The custom versatile flash driver used by the default U-Boot
   versatile configuration doesn't play well with Qemu flash emulation
   for reasons that I haven't investigated.

   At least one people in 2005 sent patches to convert U-Boot versatile
   to use the generic CFI flash driver, but it seems that the patches
   haven't been integrated:
   http://lists.denx.de/pipermail/u-boot/2005-October/012334.html

   I'd be glad to send the patch to the U-Boot people, but I couldn't
   test it on the hardware, so I'm not sure they work properly.

 * Switch to an external phy for the ethernet adapter. This works on
   Qemu, but probably won't work on the real hardware. But again, I
   couldn't test this on the hardware, so I'm not sure about posting a
   patch that I haven't been able to test.

 * Tune the CFG_HZ and CFG_TIMER_CTRL to get some sane timing
   behaviour. Here again, I wasn't able to test this on real hardware.
   And I don't even understand the new values, I just changed them
   until I found a combination that "worked".

Having a U-Boot configuration that works on Qemu would certainly be
nice, but I'm not sure how to proceed with these three problems. Any
hint maybe ?

Thanks !

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

Re: [Qemu-devel] [patch 0/2] Add flash emulation to the ARM Versatile PB platform

[Jean-Christophe PLAGNIOL-VILLARD]

> > I think I'll nice to add u-boot ML too and the ARM maintainer in copy
> > maybe
> 
> Yes, maybe I should contact the U-Boot people. To get U-Boot to work on
> the Versatile PB platform, I had to make several modifications to the
> U-Boot configuration :
> 
>  * Switch to a custom versatile flash driver to the generic CFI driver.
>    The custom versatile flash driver used by the default U-Boot
>    versatile configuration doesn't play well with Qemu flash emulation
>    for reasons that I haven't investigated.
> 
>    At least one people in 2005 sent patches to convert U-Boot versatile
>    to use the generic CFI flash driver, but it seems that the patches
>    haven't been integrated:
>    http://lists.denx.de/pipermail/u-boot/2005-October/012334.html
> 
>    I'd be glad to send the patch to the U-Boot people, but I couldn't
>    test it on the hardware, so I'm not sure they work properly.
> 
>  * Switch to an external phy for the ethernet adapter. This works on
>    Qemu, but probably won't work on the real hardware. But again, I
>    couldn't test this on the hardware, so I'm not sure about posting a
>    patch that I haven't been able to test.
> 
>  * Tune the CFG_HZ and CFG_TIMER_CTRL to get some sane timing
>    behaviour. Here again, I wasn't able to test this on real hardware.
>    And I don't even understand the new values, I just changed them
>    until I found a combination that "worked".
> 
> Having a U-Boot configuration that works on Qemu would certainly be
> nice, but I'm not sure how to proceed with these three problems. Any
> hint maybe ?
I think it's important to have an emulation that respect the hardware behavior
specialy in this case where people could use also qemu to test U-Boot
modification for this board and/or others as example to check other boards
and/or others arch.

Best Regards,
J.