Message ID | 20210504131816.73272-1-laurent@vivier.eu |
---|---|
State | New |
Headers | show |
Series | m68k: virt: correctly set the initial PC | expand |
On 5/4/21 3:18 PM, Laurent Vivier wrote: > Set initial PC to the entry of the loaded kernel. > > This fixes kernel reboot with "-kernel" parameter. > > Signed-off-by: Laurent Vivier <laurent@vivier.eu> > --- > hw/m68k/virt.c | 22 +++++++++++++++++----- > 1 file changed, 17 insertions(+), 5 deletions(-) > > diff --git a/hw/m68k/virt.c b/hw/m68k/virt.c > index e9a5d4c69b97..4fb3a7ebf0f2 100644 > --- a/hw/m68k/virt.c > +++ b/hw/m68k/virt.c > @@ -88,14 +88,21 @@ > #define VIRT_VIRTIO_MMIO_BASE 0xff010000 /* MMIO: 0xff010000 - 0xff01ffff */ > #define VIRT_VIRTIO_IRQ_BASE PIC_IRQ(2, 1) /* PIC: 2, 3, 4, 5, IRQ: ALL */ > > +typedef struct { > + M68kCPU *cpu; > + hwaddr initial_pc; > + hwaddr initial_stack; > +} ResetInfo; > + > static void main_cpu_reset(void *opaque) > { > - M68kCPU *cpu = opaque; > + ResetInfo *reset_info = opaque; > + M68kCPU *cpu = reset_info->cpu; > CPUState *cs = CPU(cpu); > > cpu_reset(cs); > - cpu->env.aregs[7] = ldl_phys(cs->as, 0); > - cpu->env.pc = ldl_phys(cs->as, 4); > + cpu->env.aregs[7] = reset_info->initial_stack; > + cpu->env.pc = reset_info->initial_pc; > } > > static void virt_init(MachineState *machine) > @@ -116,6 +123,7 @@ static void virt_init(MachineState *machine) > SysBusDevice *sysbus; > hwaddr io_base; > int i; > + ResetInfo *reset_info; > > if (ram_size > 3399672 * KiB) { > /* > @@ -127,9 +135,13 @@ static void virt_init(MachineState *machine) > exit(1); > } > > + reset_info = g_malloc0(sizeof(ResetInfo)); > + > /* init CPUs */ > cpu = M68K_CPU(cpu_create(machine->cpu_type)); > - qemu_register_reset(main_cpu_reset, cpu); > + > + reset_info->cpu = cpu; > + qemu_register_reset(main_cpu_reset, reset_info); > > /* RAM */ > memory_region_add_subregion(get_system_memory(), 0, machine->ram); > @@ -209,7 +221,7 @@ static void virt_init(MachineState *machine) > error_report("could not load kernel '%s'", kernel_filename); > exit(1); > } > - stl_phys(cs->as, 4, elf_entry); /* reset initial PC */ > + reset_info->initial_pc = elf_entry; Missing the stack? reset_info->initial_stack = ldl_phys(cs->as, 0); > parameters_base = (high + 1) & ~1; > > BOOTINFO1(cs->as, parameters_base, BI_MACHTYPE, MACH_VIRT); >
Le 04/05/2021 à 16:13, Philippe Mathieu-Daudé a écrit : > On 5/4/21 3:18 PM, Laurent Vivier wrote: >> Set initial PC to the entry of the loaded kernel. >> >> This fixes kernel reboot with "-kernel" parameter. >> >> Signed-off-by: Laurent Vivier <laurent@vivier.eu> >> --- >> hw/m68k/virt.c | 22 +++++++++++++++++----- >> 1 file changed, 17 insertions(+), 5 deletions(-) >> >> diff --git a/hw/m68k/virt.c b/hw/m68k/virt.c >> index e9a5d4c69b97..4fb3a7ebf0f2 100644 >> --- a/hw/m68k/virt.c >> +++ b/hw/m68k/virt.c >> @@ -88,14 +88,21 @@ >> #define VIRT_VIRTIO_MMIO_BASE 0xff010000 /* MMIO: 0xff010000 - 0xff01ffff */ >> #define VIRT_VIRTIO_IRQ_BASE PIC_IRQ(2, 1) /* PIC: 2, 3, 4, 5, IRQ: ALL */ >> >> +typedef struct { >> + M68kCPU *cpu; >> + hwaddr initial_pc; >> + hwaddr initial_stack; >> +} ResetInfo; >> + >> static void main_cpu_reset(void *opaque) >> { >> - M68kCPU *cpu = opaque; >> + ResetInfo *reset_info = opaque; >> + M68kCPU *cpu = reset_info->cpu; >> CPUState *cs = CPU(cpu); >> >> cpu_reset(cs); >> - cpu->env.aregs[7] = ldl_phys(cs->as, 0); >> - cpu->env.pc = ldl_phys(cs->as, 4); >> + cpu->env.aregs[7] = reset_info->initial_stack; >> + cpu->env.pc = reset_info->initial_pc; >> } >> >> static void virt_init(MachineState *machine) >> @@ -116,6 +123,7 @@ static void virt_init(MachineState *machine) >> SysBusDevice *sysbus; >> hwaddr io_base; >> int i; >> + ResetInfo *reset_info; >> >> if (ram_size > 3399672 * KiB) { >> /* >> @@ -127,9 +135,13 @@ static void virt_init(MachineState *machine) >> exit(1); >> } >> >> + reset_info = g_malloc0(sizeof(ResetInfo)); >> + >> /* init CPUs */ >> cpu = M68K_CPU(cpu_create(machine->cpu_type)); >> - qemu_register_reset(main_cpu_reset, cpu); >> + >> + reset_info->cpu = cpu; >> + qemu_register_reset(main_cpu_reset, reset_info); >> >> /* RAM */ >> memory_region_add_subregion(get_system_memory(), 0, machine->ram); >> @@ -209,7 +221,7 @@ static void virt_init(MachineState *machine) >> error_report("could not load kernel '%s'", kernel_filename); >> exit(1); >> } >> - stl_phys(cs->as, 4, elf_entry); /* reset initial PC */ >> + reset_info->initial_pc = elf_entry; > Missing the stack? > > reset_info->initial_stack = ldl_phys(cs->as, 0); No, as it's a g_malloc0(), initial_stack is set to 0, so aregs[7] (SP) will be reset to 0 on reboot. We could also set it to ram_size if we want something usable, but it's not needed for the kernel entry point. Thanks, Laurent
On 5/4/21 4:20 PM, Laurent Vivier wrote: > Le 04/05/2021 à 16:13, Philippe Mathieu-Daudé a écrit : >> On 5/4/21 3:18 PM, Laurent Vivier wrote: >>> Set initial PC to the entry of the loaded kernel. >>> >>> This fixes kernel reboot with "-kernel" parameter. >>> >>> Signed-off-by: Laurent Vivier <laurent@vivier.eu> >>> --- >>> hw/m68k/virt.c | 22 +++++++++++++++++----- >>> 1 file changed, 17 insertions(+), 5 deletions(-) >>> >>> diff --git a/hw/m68k/virt.c b/hw/m68k/virt.c >>> index e9a5d4c69b97..4fb3a7ebf0f2 100644 >>> --- a/hw/m68k/virt.c >>> +++ b/hw/m68k/virt.c >>> @@ -88,14 +88,21 @@ >>> #define VIRT_VIRTIO_MMIO_BASE 0xff010000 /* MMIO: 0xff010000 - 0xff01ffff */ >>> #define VIRT_VIRTIO_IRQ_BASE PIC_IRQ(2, 1) /* PIC: 2, 3, 4, 5, IRQ: ALL */ >>> >>> +typedef struct { >>> + M68kCPU *cpu; >>> + hwaddr initial_pc; >>> + hwaddr initial_stack; >>> +} ResetInfo; >>> + >>> static void main_cpu_reset(void *opaque) >>> { >>> - M68kCPU *cpu = opaque; >>> + ResetInfo *reset_info = opaque; >>> + M68kCPU *cpu = reset_info->cpu; >>> CPUState *cs = CPU(cpu); >>> >>> cpu_reset(cs); >>> - cpu->env.aregs[7] = ldl_phys(cs->as, 0); >>> - cpu->env.pc = ldl_phys(cs->as, 4); >>> + cpu->env.aregs[7] = reset_info->initial_stack; >>> + cpu->env.pc = reset_info->initial_pc; >>> } >>> >>> static void virt_init(MachineState *machine) >>> @@ -116,6 +123,7 @@ static void virt_init(MachineState *machine) >>> SysBusDevice *sysbus; >>> hwaddr io_base; >>> int i; >>> + ResetInfo *reset_info; >>> >>> if (ram_size > 3399672 * KiB) { >>> /* >>> @@ -127,9 +135,13 @@ static void virt_init(MachineState *machine) >>> exit(1); >>> } >>> >>> + reset_info = g_malloc0(sizeof(ResetInfo)); >>> + >>> /* init CPUs */ >>> cpu = M68K_CPU(cpu_create(machine->cpu_type)); >>> - qemu_register_reset(main_cpu_reset, cpu); >>> + >>> + reset_info->cpu = cpu; >>> + qemu_register_reset(main_cpu_reset, reset_info); >>> >>> /* RAM */ >>> memory_region_add_subregion(get_system_memory(), 0, machine->ram); >>> @@ -209,7 +221,7 @@ static void virt_init(MachineState *machine) >>> error_report("could not load kernel '%s'", kernel_filename); >>> exit(1); >>> } >>> - stl_phys(cs->as, 4, elf_entry); /* reset initial PC */ >>> + reset_info->initial_pc = elf_entry; >> Missing the stack? >> >> reset_info->initial_stack = ldl_phys(cs->as, 0); > > No, as it's a g_malloc0(), initial_stack is set to 0, so aregs[7] (SP) will be reset to 0 on reboot. > We could also set it to ram_size if we want something usable, but it's not needed for the kernel > entry point. Indeed I missed g_malloc*0*. It would be clearer to use g_malloc() and explicitly set the initial stack IMHO. > > Thanks, > > Laurent > >
diff --git a/hw/m68k/virt.c b/hw/m68k/virt.c index e9a5d4c69b97..4fb3a7ebf0f2 100644 --- a/hw/m68k/virt.c +++ b/hw/m68k/virt.c @@ -88,14 +88,21 @@ #define VIRT_VIRTIO_MMIO_BASE 0xff010000 /* MMIO: 0xff010000 - 0xff01ffff */ #define VIRT_VIRTIO_IRQ_BASE PIC_IRQ(2, 1) /* PIC: 2, 3, 4, 5, IRQ: ALL */ +typedef struct { + M68kCPU *cpu; + hwaddr initial_pc; + hwaddr initial_stack; +} ResetInfo; + static void main_cpu_reset(void *opaque) { - M68kCPU *cpu = opaque; + ResetInfo *reset_info = opaque; + M68kCPU *cpu = reset_info->cpu; CPUState *cs = CPU(cpu); cpu_reset(cs); - cpu->env.aregs[7] = ldl_phys(cs->as, 0); - cpu->env.pc = ldl_phys(cs->as, 4); + cpu->env.aregs[7] = reset_info->initial_stack; + cpu->env.pc = reset_info->initial_pc; } static void virt_init(MachineState *machine) @@ -116,6 +123,7 @@ static void virt_init(MachineState *machine) SysBusDevice *sysbus; hwaddr io_base; int i; + ResetInfo *reset_info; if (ram_size > 3399672 * KiB) { /* @@ -127,9 +135,13 @@ static void virt_init(MachineState *machine) exit(1); } + reset_info = g_malloc0(sizeof(ResetInfo)); + /* init CPUs */ cpu = M68K_CPU(cpu_create(machine->cpu_type)); - qemu_register_reset(main_cpu_reset, cpu); + + reset_info->cpu = cpu; + qemu_register_reset(main_cpu_reset, reset_info); /* RAM */ memory_region_add_subregion(get_system_memory(), 0, machine->ram); @@ -209,7 +221,7 @@ static void virt_init(MachineState *machine) error_report("could not load kernel '%s'", kernel_filename); exit(1); } - stl_phys(cs->as, 4, elf_entry); /* reset initial PC */ + reset_info->initial_pc = elf_entry; parameters_base = (high + 1) & ~1; BOOTINFO1(cs->as, parameters_base, BI_MACHTYPE, MACH_VIRT);
Set initial PC to the entry of the loaded kernel. This fixes kernel reboot with "-kernel" parameter. Signed-off-by: Laurent Vivier <laurent@vivier.eu> --- hw/m68k/virt.c | 22 +++++++++++++++++----- 1 file changed, 17 insertions(+), 5 deletions(-)