On Sat, May 29, 2010 at 8:51 PM, Aurelien Jarno <aurel...@aurel32.net> wrote:
> On Sat, May 29, 2010 at 08:42:52PM +0200, Lars Munch wrote:
>> On Fri, May 28, 2010 at 9:24 PM, Aurelien Jarno <aurel...@aurel32.net> wrote:
>> > On Sat, May 08, 2010 at 10:43:35PM +0200, Lars Munch wrote:
>> >> Booting an arm kernel has been broken a while when booting from non zero
>> >> start
>> >> address. This is due to the order of events: board init loads the kernel
>> >> and
>> >> sets register 15 to the start address and then qemu_system_reset reset
>> >> the cpu
>> >> making register 15 zero again.
>> >>
>> >> This patch fixes the usage of the register 15 start address trick in
>> >> combination with arm_load_kernel.
>> >>
>> >> Signed-off-by: Lars Munch <l...@segv.dk>
>> >> ---
>> >> hw/arm_boot.c | 1 +
>> >> hw/gumstix.c | 4 ----
>> >> hw/mainstone.c | 3 ---
>> >> hw/nseries.c | 7 -------
>> >> hw/omap_sx1.c | 5 -----
>> >> hw/palm.c | 4 ----
>> >> hw/spitz.c | 3 ---
>> >> hw/tosa.c | 3 ---
>> >> target-arm/helper.c | 1 -
>> >> 9 files changed, 1 insertions(+), 30 deletions(-)
>> >>
>> >> diff --git a/hw/arm_boot.c b/hw/arm_boot.c
>> >> index df031a5..620550b 100644
>> >> --- a/hw/arm_boot.c
>> >> +++ b/hw/arm_boot.c
>> >> @@ -187,6 +187,7 @@ static void main_cpu_reset(void *opaque)
>> >> env->regs[15] = info->entry & 0xfffffffe;
>> >> env->thumb = info->entry & 1;
>> >> } else {
>> >> + env->regs[15] = info->loader_start;
>> >> if (old_param) {
>> >> set_kernel_args_old(info, info->initrd_size,
>> >> info->loader_start);
>> >
>> > This parts looks fine.
>> >
>> >> diff --git a/hw/gumstix.c b/hw/gumstix.c
>> >> index 3fd31f4..b64e04e 100644
>> >> --- a/hw/gumstix.c
>> >> +++ b/hw/gumstix.c
>> >> @@ -74,8 +74,6 @@ static void connex_init(ram_addr_t ram_size,
>> >> exit(1);
>> >> }
>> >>
>> >> - cpu->env->regs[15] = 0x00000000;
>> >> -
>> >> /* Interrupt line of NIC is connected to GPIO line 36 */
>> >> smc91c111_init(&nd_table[0], 0x04000300,
>> >> pxa2xx_gpio_in_get(cpu->gpio)[36]);
>> >> @@ -114,8 +112,6 @@ static void verdex_init(ram_addr_t ram_size,
>> >> exit(1);
>> >> }
>> >>
>> >> - cpu->env->regs[15] = 0x00000000;
>> >> -
>> >> /* Interrupt line of NIC is connected to GPIO line 99 */
>> >> smc91c111_init(&nd_table[0], 0x04000300,
>> >> pxa2xx_gpio_in_get(cpu->gpio)[99]);
>> >> diff --git a/hw/mainstone.c b/hw/mainstone.c
>> >> index a4379e3..54bacfb 100644
>> >> --- a/hw/mainstone.c
>> >> +++ b/hw/mainstone.c
>> >> @@ -89,9 +89,6 @@ static void mainstone_common_init(ram_addr_t ram_size,
>> >> cpu_register_physical_memory(0, MAINSTONE_ROM,
>> >> qemu_ram_alloc(MAINSTONE_ROM) | IO_MEM_ROM);
>> >>
>> >> - /* Setup initial (reset) machine state */
>> >> - cpu->env->regs[15] = mainstone_binfo.loader_start;
>> >> -
>> >> #ifdef TARGET_WORDS_BIGENDIAN
>> >> be = 1;
>> >> #else
>> >> diff --git a/hw/nseries.c b/hw/nseries.c
>> >> index 0273eee..04a028d 100644
>> >> --- a/hw/nseries.c
>> >> +++ b/hw/nseries.c
>> >> @@ -1016,7 +1016,6 @@ static void n8x0_boot_init(void *opaque)
>> >> n800_dss_init(&s->blizzard);
>> >>
>> >> /* CPU setup */
>> >> - s->cpu->env->regs[15] = s->cpu->env->boot_info->loader_start;
>> >> s->cpu->env->GE = 0x5;
>> >>
>> >> /* If the machine has a slided keyboard, open it */
>> >> @@ -1317,11 +1316,6 @@ static void n8x0_init(ram_addr_t ram_size, const
>> >> char *boot_device,
>> >> if (usb_enabled)
>> >> n8x0_usb_setup(s);
>> >>
>> >> - /* Setup initial (reset) machine state */
>> >> -
>> >> - /* Start at the OneNAND bootloader. */
>> >> - s->cpu->env->regs[15] = 0;
>> >> -
>> >> if (kernel_filename) {
>> >> /* Or at the linux loader. */
>> >> binfo->kernel_filename = kernel_filename;
>> >> @@ -1330,7 +1324,6 @@ static void n8x0_init(ram_addr_t ram_size, const
>> >> char *boot_device,
>> >> arm_load_kernel(s->cpu->env, binfo);
>> >>
>> >> qemu_register_reset(n8x0_boot_init, s);
>> >> - n8x0_boot_init(s);
>> >> }
>> >>
>> >> if (option_rom[0] && (boot_device[0] == 'n' || !kernel_filename)) {
>> >> diff --git a/hw/omap_sx1.c b/hw/omap_sx1.c
>> >> index ca0a7d1..2e9879f 100644
>> >> --- a/hw/omap_sx1.c
>> >> +++ b/hw/omap_sx1.c
>> >> @@ -195,15 +195,10 @@ static void sx1_init(ram_addr_t ram_size,
>> >>
>> >> /* Load the kernel. */
>> >> if (kernel_filename) {
>> >> - /* Start at bootloader. */
>> >> - cpu->env->regs[15] = sx1_binfo.loader_start;
>> >> -
>> >> sx1_binfo.kernel_filename = kernel_filename;
>> >> sx1_binfo.kernel_cmdline = kernel_cmdline;
>> >> sx1_binfo.initrd_filename = initrd_filename;
>> >> arm_load_kernel(cpu->env, &sx1_binfo);
>> >> - } else {
>> >> - cpu->env->regs[15] = 0x00000000;
>> >> }
>> >>
>> >> /* TODO: fix next line */
>> >> diff --git a/hw/palm.c b/hw/palm.c
>> >> index ba7c398..8db133d 100644
>> >> --- a/hw/palm.c
>> >> +++ b/hw/palm.c
>> >> @@ -243,7 +243,6 @@ static void palmte_init(ram_addr_t ram_size,
>> >> rom_size = load_image_targphys(option_rom[0], OMAP_CS0_BASE,
>> >> flash_size);
>> >> rom_loaded = 1;
>> >> - cpu->env->regs[15] = 0x00000000;
>> >> }
>> >> if (rom_size < 0) {
>> >> fprintf(stderr, "%s: error loading '%s'\n",
>> >> @@ -258,9 +257,6 @@ static void palmte_init(ram_addr_t ram_size,
>> >>
>> >> /* Load the kernel. */
>> >> if (kernel_filename) {
>> >> - /* Start at bootloader. */
>> >> - cpu->env->regs[15] = palmte_binfo.loader_start;
>> >> -
>> >> palmte_binfo.kernel_filename = kernel_filename;
>> >> palmte_binfo.kernel_cmdline = kernel_cmdline;
>> >> palmte_binfo.initrd_filename = initrd_filename;
>> >> diff --git a/hw/spitz.c b/hw/spitz.c
>> >> index c3b5cd8..4f82e24 100644
>> >> --- a/hw/spitz.c
>> >> +++ b/hw/spitz.c
>> >> @@ -993,9 +993,6 @@ static void spitz_common_init(ram_addr_t ram_size,
>> >> /* A 4.0 GB microdrive is permanently sitting in CF slot 0. */
>> >> spitz_microdrive_attach(cpu, 0);
>> >>
>> >> - /* Setup initial (reset) machine state */
>> >> - cpu->env->regs[15] = spitz_binfo.loader_start;
>> >> -
>> >> spitz_binfo.kernel_filename = kernel_filename;
>> >> spitz_binfo.kernel_cmdline = kernel_cmdline;
>> >> spitz_binfo.initrd_filename = initrd_filename;
>> >> diff --git a/hw/tosa.c b/hw/tosa.c
>> >> index bc6591f..fbe8d8c 100644
>> >> --- a/hw/tosa.c
>> >> +++ b/hw/tosa.c
>> >> @@ -229,9 +229,6 @@ static void tosa_init(ram_addr_t ram_size,
>> >>
>> >> tosa_tg_init(cpu);
>> >>
>> >> - /* Setup initial (reset) machine state */
>> >> - cpu->env->regs[15] = tosa_binfo.loader_start;
>> >> -
>> >> tosa_binfo.kernel_filename = kernel_filename;
>> >> tosa_binfo.kernel_cmdline = kernel_cmdline;
>> >> tosa_binfo.initrd_filename = initrd_filename;
>> >> diff --git a/target-arm/helper.c b/target-arm/helper.c
>> >> index 99e0394..63e5dc7 100644
>> >> --- a/target-arm/helper.c
>> >> +++ b/target-arm/helper.c
>> >> @@ -207,7 +207,6 @@ void cpu_reset(CPUARMState *env)
>> >> #else
>> >> /* SVC mode with interrupts disabled. */
>> >> env->uncached_cpsr = ARM_CPU_MODE_SVC | CPSR_A | CPSR_F | CPSR_I;
>> >> - env->regs[15] = 0;
>> >> /* On ARMv7-M the CPSR_I is the value of the PRIMASK register, and is
>> >> clear at reset. Initial SP and PC are loaded from ROM. */
>> >> if (IS_M(env)) {
>> >
>> > This part doesn't. The register reset should be kept in case in case the
>> > test "if (info)" in main_cpu_reset() is false.
>>
>> All the "regs[15] = xyz" above are unneeded now as they are all used
>> in combination with arm_boot_kernel with a valid info struct.
>
> Agreed.
>
>> The last "env->regs[15] = 0" is redundant as the register is already
>> zeroed at that point.
>>
>
> Where is it zeroed?
In this memset(env, 0, offsetof(CPUARMState, breakpoints)); in
cpu_reset (line 201 in target-arm/helper.c)
