On Sun, Jan 19, 2020 at 8:14 PM Philippe Mathieu-Daudé <philmd@redhat.com>
wrote:

> On 1/19/20 1:50 AM, Niek Linnenbank wrote:
> > A real Allwinner H3 SoC contains a Boot ROM which is the
> > first code that runs right after the SoC is powered on.
> > The Boot ROM is responsible for loading user code (e.g. a bootloader)
> > from any of the supported external devices and writing the downloaded
> > code to internal SRAM. After loading the SoC begins executing the code
> > written to SRAM.
> >
> > This commits adds emulation of the Boot ROM firmware setup functionality
> > by loading user code from SD card in the A1 SRAM. While the A1 SRAM is
> > 64KiB, we limit the size to 32KiB because the real H3 Boot ROM also
> rejects
> > sizes larger than 32KiB. For reference, this behaviour is documented
> > by the Linux Sunxi project wiki at:
> >
> >    https://linux-sunxi.org/BROM#U-Boot_SPL_limitations
> >
> > Signed-off-by: Niek Linnenbank <nieklinnenbank@gmail.com>
> > ---
> >   include/hw/arm/allwinner-h3.h | 23 +++++++++++++++++++++++
> >   hw/arm/allwinner-h3.c         | 28 ++++++++++++++++++++++++++++
> >   hw/arm/orangepi.c             |  5 +++++
> >   3 files changed, 56 insertions(+)
> >
> > diff --git a/include/hw/arm/allwinner-h3.h
> b/include/hw/arm/allwinner-h3.h
> > index f9b9a02373..f5e16266cd 100644
> > --- a/include/hw/arm/allwinner-h3.h
> > +++ b/include/hw/arm/allwinner-h3.h
> > @@ -46,6 +46,7 @@
> >   #include "hw/sd/allwinner-sdhost.h"
> >   #include "hw/net/allwinner-sun8i-emac.h"
> >   #include "target/arm/cpu.h"
> > +#include "sysemu/block-backend.h"
> >
> >   /**
> >    * Allwinner H3 device list
> > @@ -129,4 +130,26 @@ typedef struct AwH3State {
> >       MemoryRegion sram_c;
> >   } AwH3State;
> >
> > +/**
> > + * Emulate Boot ROM firmware setup functionality.
> > + *
> > + * A real Allwinner H3 SoC contains a Boot ROM
> > + * which is the first code that runs right after
> > + * the SoC is powered on. The Boot ROM is responsible
> > + * for loading user code (e.g. a bootloader) from any
> > + * of the supported external devices and writing the
> > + * downloaded code to internal SRAM. After loading the SoC
> > + * begins executing the code written to SRAM.
> > + *
> > + * This function emulates the Boot ROM by copying 32 KiB
> > + * of data from the given block device and writes it to
> > + * the start of the first internal SRAM memory.
> > + *
> > + * @s: Allwinner H3 state object pointer
> > + * @blk: Block backend device object pointer
> > + * @errp: Error object pointer for raising errors
> > + */
> > +void allwinner_h3_bootrom_setup(AwH3State *s, BlockBackend *blk,
> > +                                Error **errp);
> > +
> >   #endif /* HW_ARM_ALLWINNER_H3_H */
> > diff --git a/hw/arm/allwinner-h3.c b/hw/arm/allwinner-h3.c
> > index 1085223812..3d0470825a 100644
> > --- a/hw/arm/allwinner-h3.c
> > +++ b/hw/arm/allwinner-h3.c
> > @@ -29,6 +29,7 @@
> >   #include "hw/char/serial.h"
> >   #include "hw/misc/unimp.h"
> >   #include "hw/usb/hcd-ehci.h"
> > +#include "hw/loader.h"
> >   #include "sysemu/sysemu.h"
> >   #include "hw/arm/allwinner-h3.h"
> >
> > @@ -170,6 +171,33 @@ enum {
> >       AW_H3_GIC_NUM_SPI       = 128
> >   };
> >
> > +void allwinner_h3_bootrom_setup(AwH3State *s, BlockBackend *blk, Error
> **errp)
> > +{
> > +    uint8_t *buffer;
> > +    int64_t rom_size = 32 * KiB;
> > +
> > +    int64_t blk_size = blk_getlength(blk);
> > +    if (blk_size <= 0) {
> > +        error_setg(errp, "%s: failed to get BlockBackend size",
> __func__);
> > +        return;
> > +    }
> > +
> > +    if (rom_size > blk_size) {
> > +        rom_size = blk_size;
>
> This doesn't seem correct, have you tried to use a 1MB file?
>
> This can't be bigger than the SRAM size, 64KB.
>

This check was supposed to take into account the possibility that
the BlockBackend is smaller than the rom_size. However, if the rom cannot
be read from the BlockBackend it will return an error code anyway.

So the check can simply be removed. Thanks!


>
> > +    }
> > +
> > +    buffer = g_new0(uint8_t, rom_size);
> > +    if (blk_pread(blk, 8 * KiB, buffer, rom_size) < 0) {
> > +        error_setg(errp, "%s: failed to read BlockBackend data",
> __func__);
> > +        return;
> > +    }
> > +
> > +    rom_add_blob("allwinner-h3.bootrom", buffer, rom_size,
> > +                  rom_size, s->memmap[AW_H3_SRAM_A1],
> > +                  NULL, NULL, NULL, NULL, false);
> > +    g_free(buffer);
> > +}
> > +
> >   static void allwinner_h3_init(Object *obj)
> >   {
> >       AwH3State *s = AW_H3(obj);
> > diff --git a/hw/arm/orangepi.c b/hw/arm/orangepi.c
> > index 25bf85f8fc..9d4c79885e 100644
> > --- a/hw/arm/orangepi.c
> > +++ b/hw/arm/orangepi.c
> > @@ -95,6 +95,11 @@ static void orangepi_init(MachineState *machine)
> >       memory_region_add_subregion(get_system_memory(),
> s->h3->memmap[AW_H3_SDRAM],
> >                                   &s->sdram);
> >
> > +    /* Load target kernel or start using BootROM */
> > +    if (!machine->kernel_filename && blk_is_available(blk)) {
> > +        /* Use Boot ROM to copy data from SD card to SRAM */
> > +        allwinner_h3_bootrom_setup(s->h3, blk, &error_fatal);
> allwinner_h3_bootrom_setup() doesn't need the errp argument, you can use
> error_fatal directly there.
>

OK, I'll use error_fatal and remove the errp argument.

Regards,
Niek


>
> > +    }
> >       orangepi_binfo.loader_start = s->h3->memmap[AW_H3_SDRAM];
> >       orangepi_binfo.ram_size = machine->ram_size;
> >       arm_load_kernel(ARM_CPU(first_cpu), machine, &orangepi_binfo);
> >
>
>

-- 
Niek Linnenbank