Hi Alison,
I'll wait for a new version based on Alex's feedback before I test.
The change looks like it should work, so I'm happy to wait, unless you feel thjere is a need to test it sooner.
Thanks for the quick response.
Regards, Ryan.
On 13 Jan 2017 08:16, "Alison Wang" alison.wang@nxp.com wrote:
Hi, Ryan,
This patch is to fix the issue about a warning for ARMv8 64-bit kernel you reported before. I have tested on my LayerScape boards. Please review and try on your boards too.
Thanks.
Best Regards, Alison Wang
-----Original Message----- From: Alison Wang [mailto:b18965@freescale.com] Sent: Friday, January 13, 2017 3:50 PM To: york sun york.sun@nxp.com; ryan.harkin@linaro.org; agraf@suse.de; Scott Wood scott.wood@nxp.com; Stuart Yoder stuart.yoder@nxp.com; Leo Li leoyang.li@nxp.com; fenghua@phytium.com.cn; linus.walleij@linaro.org; u-boot@lists.denx.de Cc: Jason Jin jason.jin@nxp.com; Alison Wang alison.wang@nxp.com Subject: [PATCH] armv8: aarch64: Fix the warning about x1-x3 nonzero issue
For 64-bit kernel, there is a warning about x1-x3 nonzero in violation of boot protocol. x3 should be reset to zero before jumping to the kernel.
This patch will adjust the parameters to transfer and make sure x3 is zero.
Signed-off-by: Alison Wang alison.wang@nxp.com
arch/arm/cpu/armv8/transition.S | 44 +++++++++++++++++++++++++++++++++++++---- 1 file changed, 40 insertions(+), 4 deletions(-)
diff --git a/arch/arm/cpu/armv8/transition.S b/arch/arm/cpu/armv8/transition.S index adb9f35..06b6664 100644 --- a/arch/arm/cpu/armv8/transition.S +++ b/arch/arm/cpu/armv8/transition.S @@ -26,9 +26,27 @@ ENTRY(armv8_switch_to_el2) * if CONFIG_ARMV8_SWITCH_TO_EL1 is defined. * When running in EL2 now, jump to the * address saved in x3.
** For 64-bit kernel, there is a warning about* x1-x3 nonzero in violation of boot protocol.* x3 should be reset to zero before jumping to* the kernel. Use x4 instead of x3 as parameter. */
br x3-1: armv8_switch_to_el2_m x3, x4, x5
mov x4, x3mov x3, #0br x4+1:
/** For 64-bit kernel, there is a warning about* x1-x3 nonzero in violation of boot protocol.* x3 should be reset to zero before jumping to* the kernel. Use x4, x5, x6 instead of x3, x4,* x5 as parameters.*/mov x5, x4mov x4, x3mov x3, #0armv8_switch_to_el2_m x4, x5, x6ENDPROC(armv8_switch_to_el2)
ENTRY(armv8_switch_to_el1) @@ -36,9 +54,27 @@ ENTRY(armv8_switch_to_el1) 0: /* x3 is kernel entry point. When running in EL1 * now, jump to the address saved in x3.
** For 64-bit kernel, there is a warning about* x1-x3 nonzero in violation of boot protocol.* x3 should be reset to zero before jumping to* the kernel. Use x4 instead of x3 as parameter.*/mov x4, x3mov x3, #0br x4+1:
/** For 64-bit kernel, there is a warning about* x1-x3 nonzero in violation of boot protocol.* x3 should be reset to zero before jumping to* the kernel. Use x4, x5, x6 instead of x3, x4,* x5 as parameters. */
br x3-1: armv8_switch_to_el1_m x3, x4, x5
mov x5, x4mov x4, x3mov x3, #0armv8_switch_to_el1_m x4, x5, x6ENDPROC(armv8_switch_to_el1)
WEAK(armv8_el2_to_aarch32)
2.1.0.27.g96db324