On Tue, Jan 14, 2020 at 12:28 AM Philippe Mathieu-Daudé
<address@hidden <mailto:address@hidden>> wrote:
On 1/8/20 9:00 PM, 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.
>
> Signed-off-by: Niek Linnenbank <address@hidden
<mailto:address@hidden>>
> ---
> include/hw/arm/allwinner-h3.h | 23 +++++++++++++++++++++++
> hw/arm/allwinner-h3.c | 28 ++++++++++++++++++++++++++++
> hw/arm/orangepi.c | 3 +++
> 3 files changed, 54 insertions(+)
>
> diff --git a/include/hw/arm/allwinner-h3.h
b/include/hw/arm/allwinner-h3.h
> index 5d74cca28e..4b66227ac4 100644
> --- a/include/hw/arm/allwinner-h3.h
> +++ b/include/hw/arm/allwinner-h3.h
> @@ -50,6 +50,7 @@
> #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
> @@ -130,4 +131,26 @@ 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 e692432b4e..e7b768ad5b 100644
> --- a/hw/arm/allwinner-h3.c
> +++ b/hw/arm/allwinner-h3.c
> @@ -27,6 +27,7 @@
> #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"
>
> @@ -168,6 +169,33 @@ 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;
Why restrict to 32K? The A1 SRAM is 64K.
The reason is that the actual Boot ROM on the H3 also uses 32K:
https://linux-sunxi.org/BROM
See the 'U-Boot SPL Limitations' table at the end of the page.
You can see the comment in the table there regarding the 32 KiB:
"Sizes larger than 32 KiB are rejected by the BROM. Exactly 32 KiB is
fine, as verified by writing a special pattern at the end of the SPL and
checking it in the SRAM."
Probably it would not harm to increase it to the full size of the SRAM,
but I tried to model
the behavior as close to the real hardware as possible.