On Tue, Jan 27, 2015 at 01:56:12PM -0500, Frank Bormann wrote:

Hi,

I was wondering if I could have any input on the patch below activating hypervisor mode on TI OMAP5-based SoC. The patch essentially uses the on-chip ROM code API to enable hypervisor mode on the primary A15 core and goes in tandem with a Linux kernel patch recently accepted into omap-for-v3.19/fixes that checks hypervisor mode on the primary A15 core and sets it accordingly on additional cores being activated.

I am aware that there is some development going on for ARM's PSCI that amongst other things is supposed to deal with hypervisor activation in a more generic fashion and I am wondering if there is any preference on how to properly activate hypervisor mode for the TI SoCs mentioned above.

Thanks, Frank

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u-boot patch:

Enable hypervisor mode for AM5726

Well it actually applies to AM57xx and OMAP54xx as far as I can tell.

The DRA7XX (AM57xx) borrowed that part of the romcode from the OMAP5 as far as I know.

Perhaps DRA7XX in the name should be something that applies to both TI Cortex-A15 designs. I don't know what the Keystone models do.

---

arch/arm/cpu/armv7/omap-common/lowlevel_init.S | 13 +++++++++++++ 1 file changed, 13 insertions(+)

diff --git a/arch/arm/cpu/armv7/omap-common/lowlevel_init.S b/arch/arm/cpu/armv7/omap-common/lowlevel_init.S index 86c0e42..696da4b 100644 --- a/arch/arm/cpu/armv7/omap-common/lowlevel_init.S +++ b/arch/arm/cpu/armv7/omap-common/lowlevel_init.S @@ -19,7 +19,20 @@ ENTRY(save_boot_params) ldr r1, =OMAP_SRAM_SCRATCH_BOOT_PARAMS str r0, [r1] +/*

• • Turn on hypervisor mode on CPU#0
• */

+#ifdef CONFIG_DRA7XX_HYPERVISOR_ON

• mov r0, lr @ This is a great place to switch into hyp mode

• 		@ only the r0 was needed from _start and is now
  

• 		@ free; all other general purpose registers were
  

• 		@ already free.
  

• ldr r12, =0x102 @ Set PL310 control register - value in R0
• .word 0xe1600070 @ SMC #0 - hand assembled because -march=armv5

• 		@ call ROM Code API to set control register
  

+#else bx lr +#endif /* CONFIG_DRA7XX_HYPERVISOR_ON */ ENDPROC(save_boot_params) ENTRY(set_pl310_ctrl_reg)

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Link to the corresponding Linux kernel patch:

http://linux-kernel.2935.n7.nabble.com/PATCH-ARM-omap5-dra7xx-Enable-booting...