On Sat, Aug 2, 2014 at 9:41 AM, Peter Crosthwaite
<crosthwaitepe...@gmail.com> wrote:
> ARMv7M has it's own bootloader (separate from the regular ARM
> bootloader) that is elf aware. It is able to load elfs but it does
> not set the program counter to the elf entry point. Make it more
> consistent with the regular ARM bootloader by setting the program
> counter to the given elf entry point.
>
> Signed-off-by: Peter Crosthwaite <crosthwaite.pe...@gmail.com>
> ---
> hw/arm/armv7m.c | 19 ++++++++++++++++---
> 1 file changed, 16 insertions(+), 3 deletions(-)
>
> diff --git a/hw/arm/armv7m.c b/hw/arm/armv7m.c
> index 397e8df..d1b983f 100644
> --- a/hw/arm/armv7m.c
> +++ b/hw/arm/armv7m.c
> @@ -155,11 +155,18 @@ static void armv7m_bitband_init(void)
>
> /* Board init. */
>
> +typedef struct ARMV7MResetArgs {
> + ARMCPU *cpu;
> + uint32_t reset_pc;
> +} ARMV7MResetArgs;
> +
> static void armv7m_reset(void *opaque)
> {
> - ARMCPU *cpu = opaque;
> + ARMV7MResetArgs *args = opaque;
>
> - cpu_reset(CPU(cpu));
> + cpu_reset(CPU(args->cpu));
> + args->cpu->env.regs[15] = args->reset_pc;
> + args->cpu->env.thumb = args->reset_pc & 1;
> }
This breaks a simple test case that I have. It now starts at a an
address one one bit larger but causes the program to hang.
If the 'cpu_reset(CPU(args->cpu))' is moved to the end of the function
the test boots (the same as it did before).
>
> /* Init CPU and memory for a v7-M based board.
> @@ -183,6 +190,7 @@ qemu_irq *armv7m_init(MemoryRegion *address_space_mem,
> MemoryRegion *sram = g_new(MemoryRegion, 1);
> MemoryRegion *flash = g_new(MemoryRegion, 1);
> MemoryRegion *hack = g_new(MemoryRegion, 1);
> + ARMV7MResetArgs reset_args;
>
> flash_size *= 1024;
> sram_size *= 1024;
> @@ -259,7 +267,12 @@ qemu_irq *armv7m_init(MemoryRegion *address_space_mem,
> vmstate_register_ram_global(hack);
> memory_region_add_subregion(address_space_mem, 0xfffff000, hack);
>
> - qemu_register_reset(armv7m_reset, cpu);
> + reset_args = (ARMV7MResetArgs) {
> + .cpu = cpu,
> + .reset_pc = entry,
> + };
> + qemu_register_reset(armv7m_reset,
> + g_memdup(&reset_args, sizeof(reset_args)));
> return pic;
> }
>
> --
> 1.9.1
>
