On a real device, the boot ROM contains the very first instructions the CPU
executes. Also, U-Boot calls into the ROM to determine the boot device. While
we're not actually implementing this here, let's create the infrastructure and
add a dummy ROM with all zeros. This allows for implementing a ROM later without
touching the source code and even allows for users to provide their own ROMs.

The imx8mp-boot.rom was created with
`dd if=/dev/zero of=imx8mp-boot.rom bs=1 count=258048`.

Signed-off-by: Bernhard Beschow <shentey@gmail.com>
---
 MAINTAINERS                 |   1 +
 include/hw/arm/fsl-imx8mp.h |   1 +
 hw/arm/fsl-imx8mp.c         |  18 ++++++++++++++++++
 pc-bios/imx8mp-boot.rom     | Bin 0 -> 258048 bytes
 pc-bios/meson.build         |   1 +
 5 files changed, 21 insertions(+)
 create mode 100644 pc-bios/imx8mp-boot.rom

diff --git a/MAINTAINERS b/MAINTAINERS
index 94af3d90e4..ee837a3f6e 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -831,6 +831,7 @@ F: hw/pci-host/fsl_imx8m_phy.c
 F: include/hw/arm/fsl-imx8mp.h
 F: include/hw/misc/imx8mp_*.h
 F: include/hw/pci-host/fsl_imx8m_phy.h
+F: pc-bios/imx8mp*
 F: docs/system/arm/imx8mp-evk.rst
 
 MPS2 / MPS3
diff --git a/include/hw/arm/fsl-imx8mp.h b/include/hw/arm/fsl-imx8mp.h
index 5247e972b8..4dbe30f524 100644
--- a/include/hw/arm/fsl-imx8mp.h
+++ b/include/hw/arm/fsl-imx8mp.h
@@ -68,6 +68,7 @@ struct FslImx8mpState {
     DesignwarePCIEHost pcie;
     FslImx8mPciePhyState   pcie_phy;
     OrIRQState         gpt5_gpt6_irq;
+    MemoryRegion       boot_rom;
 
     uint32_t           phy_num;
     bool               phy_connected;
diff --git a/hw/arm/fsl-imx8mp.c b/hw/arm/fsl-imx8mp.c
index 14d696957a..6439639110 100644
--- a/hw/arm/fsl-imx8mp.c
+++ b/hw/arm/fsl-imx8mp.c
@@ -9,12 +9,14 @@
  */
 
 #include "qemu/osdep.h"
+#include "qemu/datadir.h"
 #include "exec/address-spaces.h"
 #include "hw/arm/bsa.h"
 #include "hw/arm/fsl-imx8mp.h"
 #include "hw/intc/arm_gicv3.h"
 #include "hw/misc/unimp.h"
 #include "hw/boards.h"
+#include "hw/loader.h"
 #include "system/system.h"
 #include "target/arm/cpu-qom.h"
 #include "qapi/qmp/qlist.h"
@@ -266,6 +268,7 @@ static void fsl_imx8mp_realize(DeviceState *dev, Error **errp)
     MachineState *ms = MACHINE(qdev_get_machine());
     FslImx8mpState *s = FSL_IMX8MP(dev);
     DeviceState *gicdev = DEVICE(&s->gic);
+    g_autofree char *filename = NULL;
     int i;
 
     if (ms->smp.cpus > FSL_IMX8MP_NUM_CPUS) {
@@ -648,10 +651,25 @@ static void fsl_imx8mp_realize(DeviceState *dev, Error **errp)
     sysbus_mmio_map(SYS_BUS_DEVICE(&s->pcie_phy), 0,
                     fsl_imx8mp_memmap[FSL_IMX8MP_PCIE_PHY1].addr);
 
+    /* ROM memory */
+    if (!memory_region_init_rom(&s->boot_rom, OBJECT(dev),
+                                fsl_imx8mp_memmap[FSL_IMX8MP_BOOT_ROM].name,
+                                fsl_imx8mp_memmap[FSL_IMX8MP_BOOT_ROM].size,
+                                errp)) {
+        return;
+    }
+    filename = qemu_find_file(QEMU_FILE_TYPE_BIOS, "imx8mp-boot.rom");
+    load_image_size(filename, memory_region_get_ram_ptr(&s->boot_rom),
+                    memory_region_size(&s->boot_rom));
+    memory_region_add_subregion(get_system_memory(),
+                                fsl_imx8mp_memmap[FSL_IMX8MP_BOOT_ROM].addr,
+                                &s->boot_rom);
+
     /* Unimplemented devices */
     for (i = 0; i < ARRAY_SIZE(fsl_imx8mp_memmap); i++) {
         switch (i) {
         case FSL_IMX8MP_ANA_PLL:
+        case FSL_IMX8MP_BOOT_ROM:
         case FSL_IMX8MP_CCM:
         case FSL_IMX8MP_GIC_DIST:
         case FSL_IMX8MP_GIC_REDIST:
diff --git a/pc-bios/imx8mp-boot.rom b/pc-bios/imx8mp-boot.rom
new file mode 100644
index 0000000000000000000000000000000000000000..5324b5eed200e723d048f8476e4d96d45622fd4d
GIT binary patch
literal 258048
zcmeIuF#!Mo0K%a4Pi+Q&h(KY$fB^#r3>YwAz<>b*1`HT5V8DO@0|pEjFkrxd0RsjM
z7%*VKfB^#r3>YwAz<>b*1`HT5V8DO@0|pEjFkrxd0RsjM7%*VKfB^#r3>YwAz<>b*
z1`HT5V8DO@0|pEjFkrxd0RsjM7%*VKfB^#r3>YwAz<>b*1`HT5V8DO@0|pEjFkrxd
z0RsjM7%*VKfB^#r3>YwAz<>b*1`HT5V8DO@0|pEjFkrxd0RsjM7%*VKfB^#r3>YwA
zz<>b*1`HT5V8DO@0|pEjFkrxd0RsjM7%*VKfB^#r3>YwAz<>b*1`HT5V8DO@0|pEj
zFkrxd0RsjM7%*VKfB^#r3>YwAz<>b*1`HT5V8DO@0|pEjFkrxd0RsjM7%*VKfB^#r
z3>YwAz<>b*1`HT5V8DO@0|pEjFkrxd0RsjM7%*VKfB^#r3>YwAz<>b*1`HT5V8DO@
z0|pEjFkrxd0RsjM7%*VKfB^#r3>YwAz<>b*1`HT5V8DO@0|pEjFkrxd0RsjM7%*VK
zfB^#r3>YwAz<>b*1`HT5V8DO@0|pEjFkrxd0RsjM7%*VKfB^#r3>YwAz<>b*1`HT5
zV8DO@0|pEjFkrxd0RsjM7%*VKfB^#r3>YwAz<>b*1`HT5V8DO@0|pEjFkrxd0RsjM
z7%*VKfB^#r3>YwAz<>b*1`HT5V8DO@0|pEjFkrxd0RsjM7%*VKfB^#r3>YwAz<>b*
z1`HT5V8DO@0|pEjFkrxd0RsjM7%*VKfB^#r3>YwAz<>b*1`HT5V8DO@0|pEjFkrxd
z0RsjM7%*VKfB^#r3>YwAz<>b*1`HT5V8DO@0|pEjFkrxd0RsjM7%*VKfB^#r3>YwA
zz<>b*1`HT5V8DO@0|pEjFkrxd0RsjM7%*VKfB^#r3>YwAz<>b*1`HT5V8DO@0|pEj
zFkrxd0RsjM7%*VKfB^#r3>YwAz<>b*1`HT5V8DO@0|pEjFkrxd0RsjM7%*VKfB^#r
z3>YwAz<>b*1`HT5V8DO@0|pEjFkrxd0RsjM7%*VKfB^#r3>YwAz<>b*1`HT5V8DO@
z0|pEjFkrxd0RsjM7%*VKfB^#r3>YwAz<>b*1`HT5V8DO@0|pEjFkrxd0RsjM7%*VK
zfB^#r3>YwAz<>b*1`HT5V8DO@0|pEjFkrxd0RsjM7%*VKfB^#r3>YwAz<>b*1`HT5
zV8DO@0|pEjFkrxd0RsjM7%*VKfB^#r3>YwAz<>b*1`HT5V8DO@0|pEjFkrxd0RsjM
z7%*VKfB^#r3>YwAz<>b*1`HT5V8DO@0|pEjFkrxd0RsjM7%*VKfB^#r3>YwAz<>b*
z1`HT5V8DO@0|pEjFkrxd0RsjM7%*VKfB^#r3>YwAz<>b*1`HT5V8DO@0|pEjFkrxd
z0RsjM7%*VKfB^#r3>YwAz<>b*1`HT5V8DO@0|pEjFkrxd0RsjM7%*VKfB^#r3>f$Z
E2JkHa0RR91

literal 0
HcmV?d00001

diff --git a/pc-bios/meson.build b/pc-bios/meson.build
index b68b29cc7d..64d3286fdd 100644
--- a/pc-bios/meson.build
+++ b/pc-bios/meson.build
@@ -60,6 +60,7 @@ blobs = [
   'efi-virtio.rom',
   'efi-e1000e.rom',
   'efi-vmxnet3.rom',
+  'imx8mp-boot.rom',
   'qemu-nsis.bmp',
   'multiboot.bin',
   'multiboot_dma.bin',
-- 
2.48.1

On Tue, 4 Feb 2025 at 09:21, Bernhard Beschow <shentey@gmail.com> wrote:
>
> On a real device, the boot ROM contains the very first instructions the CPU
> executes. Also, U-Boot calls into the ROM to determine the boot device. While
> we're not actually implementing this here, let's create the infrastructure and
> add a dummy ROM with all zeros. This allows for implementing a ROM later without
> touching the source code and even allows for users to provide their own ROMs.
>
> The imx8mp-boot.rom was created with
> `dd if=/dev/zero of=imx8mp-boot.rom bs=1 count=258048`.

If it's all zeroes, we don't need to commit it to git as a binary,
we can generate it at build time. (We should avoid having
binaries in git as much as we can manage.)

thanks
-- PMM

Am 17. Februar 2025 13:28:42 UTC schrieb Peter Maydell <peter.maydell@linaro.org>:
>On Tue, 4 Feb 2025 at 09:21, Bernhard Beschow <shentey@gmail.com> wrote:
>>
>> On a real device, the boot ROM contains the very first instructions the CPU
>> executes. Also, U-Boot calls into the ROM to determine the boot device. While
>> we're not actually implementing this here, let's create the infrastructure and
>> add a dummy ROM with all zeros. This allows for implementing a ROM later without
>> touching the source code and even allows for users to provide their own ROMs.
>>
>> The imx8mp-boot.rom was created with
>> `dd if=/dev/zero of=imx8mp-boot.rom bs=1 count=258048`.
>
>If it's all zeroes, we don't need to commit it to git as a binary,
>we can generate it at build time. (We should avoid having
>binaries in git as much as we can manage.)

I went with this solution since it trivially works on any build platform. Any idea how to generate the file in a portable way?

Thanks,
Bernhard

>
>thanks
>-- PMM