Re: [PATCH v2 3/3] bootwrapper: Delay switch to Hyp mode until kernel entry

On 6 September 2012 18:12, Dave Martin dave.martin@linaro.org wrote:

Signed-off-by: Dave Martin dave.martin@linaro.org

This patch causes the kernel to get stuck at "Calibrating delay loop...".

I'm not sure why this happens (investigating) but if I move the enter_hyp macro call back to where it used to be (leaving the rest of the patch intact) it boots OK...

---

boot.S | 15 +++++++++++++-- semi_loader.h | 6 ++++-- 2 files changed, 17 insertions(+), 4 deletions(-)

diff --git a/boot.S b/boot.S index 128f74e..fe7acdf 100644 --- a/boot.S +++ b/boot.S @@ -96,8 +96,6 @@ start: mov r7, #0xfffffff0 smc #0 @ Set HVBAR

•   enter_hyp
  

•   @ Check CPU nr again
    mrc     p15, 0, r0, c0, c0, 5           @ MPIDR (ARMv7 only)
    and     r0, r0, #15                     @ CPU number
  

@@ -125,6 +123,8 @@ start: ldr r1, [r0] cmp r1, #0 beq 1b

•   enter_hyp
    mov     pc, r1                          @ branch to the given address
  

#endif

@@ -170,6 +170,17 @@ __semi_call: #endif mov pc, lr

+.globl __boot_kernel +__boot_kernel:

•   mov     r4, r0
  

•   stmfd   sp!, {r1-r3}
  

•   ldmia   sp, {r0-r3}
  

Since the kernel only really needs 3 arguments, it would be less hassle to drop the 4th param to boot_kernel() and then have __boot_kernel() be passed r0,r1,r2,entrypoint.

•   enter_hyp
  

•   bx      r4
  

+.type __boot_kernel, %function

•   @
    @ Data
    @
  

diff --git a/semi_loader.h b/semi_loader.h index 6afba40..29f3d63 100644 --- a/semi_loader.h +++ b/semi_loader.h @@ -90,10 +90,12 @@ struct loader_info {

void load_kernel(struct loader_info *info);

+void __boot_kernel(unsigned entry_point,

•                   unsigned r0, unsigned r1, unsigned r2, unsigned r3);
  

static void boot_kernel(struct loader_info *info, unsigned r0, unsigned r1, unsigned r2, unsigned r3) {

•   ((void (*)(unsigned, unsigned, unsigned, unsigned))info->kernel_entry)(
  

•           r0, r1, r2, r3);
  

•   __boot_kernel(info->kernel_entry, r0, r1, r2, r3);
  

}

#endif /* ! SEMI_LOADER_H */

1.7.4.1