Hi Cédric > Subject: Re: [PATCH v2 6/7] hw/arm/aspeed_ast27x0-fc: Map FMC0 flash > contents into CA35 boot ROM > > On 9/24/25 07:56, Jamin Lin wrote: > > This patch introduces a dedicated ca35_boot_rom memory region and > > copies the FMC0 flash data into it when mmio_exec is disabled. > > > > The main purpose of this change is to support the upcoming VBOOTROM , > > which can directly fetch data from FMC0 flash at the SPI boot ROM base > > address (0x100000000) without requiring any SPI controller drivers. > > That's the 'execute-in-place' case but the property activating > 'execute-in-place' is always false in this machine. Could you explain why > booting from vbootrom needs the fmc0 contents to be mapped in memory > too ? > The main goal of vbootrom is to replace bootmuc (RISC-V 32). Our current bootmuc firmware is SPL. The SPL reads flash data (image-bmc) via FMC_CS0 and loads the following components into different DRAM addresses: Trusted Firmware-A OP-TEE OS u-boot-nodtb.bin u-boot.dtb
After loading, it(BOOTMCU) releases the CA35(PSP) reset so that CA35 can run Trusted Firmware-A. The vbootrom performs the same sequence: it reads flash data (image-bmc), parses the FIT image, and loads each image into its designated DRAM address. Finally, it jumps to Trusted Firmware-A. https://github.com/google/vbootrom/blob/master/ast27x0/include/image.h#L21 https://github.com/google/vbootrom/blob/master/ast27x0/image.c#L30 https://github.com/google/vbootrom/blob/master/ast27x0/image.c#L457 https://github.com/google/vbootrom/blob/master/ast27x0/image.c#L488-L505 That is why I need to copy FMC0 data into the its memory region to make vbootrom work correctly. > > > > > Signed-off-by: Jamin Lin <jamin_...@aspeedtech.com> > > --- > > hw/arm/aspeed_ast27x0-fc.c | 14 ++++++++++++++ > > 1 file changed, 14 insertions(+) > > > > diff --git a/hw/arm/aspeed_ast27x0-fc.c b/hw/arm/aspeed_ast27x0-fc.c > > index b15cb94c39..2e6036b192 100644 > > --- a/hw/arm/aspeed_ast27x0-fc.c > > +++ b/hw/arm/aspeed_ast27x0-fc.c > > @@ -35,6 +35,7 @@ struct Ast2700FCState { > > > > MemoryRegion ca35_memory; > > MemoryRegion ca35_dram; > > + MemoryRegion ca35_boot_rom; > > MemoryRegion ssp_memory; > > MemoryRegion tsp_memory; > > > > @@ -61,7 +62,10 @@ static void ast2700fc_ca35_init(MachineState > *machine) > > Ast2700FCState *s = AST2700A1FC(machine); > > AspeedSoCState *soc; > > AspeedSoCClass *sc; > > + BlockBackend *fmc0 = NULL; > > + DeviceState *dev = NULL; > > Error **errp = NULL; > > + uint64_t rom_size; > > > > object_initialize_child(OBJECT(s), "ca35", &s->ca35, "ast2700-a1"); > > soc = ASPEED_SOC(&s->ca35); > > @@ -119,6 +123,16 @@ static void ast2700fc_ca35_init(MachineState > *machine) > > ast2700fc_board_info.ram_size = machine->ram_size; > > ast2700fc_board_info.loader_start = > > sc->memmap[ASPEED_DEV_SDRAM]; > > > > + if (!s->mmio_exec) { > > bool 'mmio_exec' is always false in this machine. Should we keep it ? > Will remove it. Thanks-Jamin > Thanks, > > C. > > > > > + dev = ssi_get_cs(soc->fmc.spi, 0); > > + fmc0 = dev ? m25p80_get_blk(dev) : NULL; > > + > > + if (fmc0) { > > + rom_size = memory_region_size(&soc->spi_boot); > > + aspeed_install_boot_rom(soc, fmc0, &s->ca35_boot_rom, > rom_size); > > + } > > + } > > + > > arm_load_kernel(ARM_CPU(first_cpu), machine, > &ast2700fc_board_info); > > } > >
