armv8: fsl-layerscape: Support loading 32-bit OS with PSCI enabled

As PSCI and secure monitor firmware framework are enabled, this patch is
to support loading 32-bit OS in such case. The default target exception
level returned to U-Boot is EL2, so the corresponding work to switch to
AArch32 EL2 and jump to 32-bit OS are done in U-Boot and secure firmware
together.

Signed-off-by: Alison Wang <alison.wang@nxp.com>
Reviewed-by: York Sun <york.sun@nxp.com>
This commit is contained in:
Alison Wang 2016-11-10 10:49:05 +08:00 committed by York Sun
parent e2c18e40b1
commit 3db86f4bbd
3 changed files with 37 additions and 0 deletions

View File

@ -50,4 +50,27 @@ ENTRY(_sec_firmware_support_psci_version)
smc #0 smc #0
ret ret
ENDPROC(_sec_firmware_support_psci_version) ENDPROC(_sec_firmware_support_psci_version)
/*
* Switch from AArch64 EL2 to AArch32 EL2
* @param inputs:
* x0: argument, zero
* x1: machine nr
* x2: fdt address
* x3: kernel entry point
* @param outputs for secure firmware:
* x0: function id
* x1: kernel entry point
* x2: machine nr
* x3: fdt address
*/
ENTRY(armv8_el2_to_aarch32)
mov x0, x3
mov x3, x2
mov x2, x1
mov x1, x0
ldr x0, =0xc000ff04
smc #0
ret
ENDPROC(armv8_el2_to_aarch32)
#endif #endif

View File

@ -13,6 +13,14 @@
ENTRY(armv8_switch_to_el2) ENTRY(armv8_switch_to_el2)
switch_el x5, 1f, 0f, 0f switch_el x5, 1f, 0f, 0f
0: 0:
cmp x4, #ES_TO_AARCH64
b.eq 2f
/*
* When loading 32-bit kernel, it will jump
* to secure firmware again, and never return.
*/
bl armv8_el2_to_aarch32
2:
/* /*
* x3 is kernel entry point or switch_to_el1 * x3 is kernel entry point or switch_to_el1
* if CONFIG_ARMV8_SWITCH_TO_EL1 is defined. * if CONFIG_ARMV8_SWITCH_TO_EL1 is defined.
@ -32,3 +40,7 @@ ENTRY(armv8_switch_to_el1)
br x3 br x3
1: armv8_switch_to_el1_m x3, x4, x5 1: armv8_switch_to_el1_m x3, x4, x5
ENDPROC(armv8_switch_to_el1) ENDPROC(armv8_switch_to_el1)
WEAK(armv8_el2_to_aarch32)
ret
ENDPROC(armv8_el2_to_aarch32)

View File

@ -215,6 +215,8 @@ void armv8_switch_to_el2(u64 args, u64 mach_nr, u64 fdt_addr,
*/ */
void armv8_switch_to_el1(u64 args, u64 mach_nr, u64 fdt_addr, void armv8_switch_to_el1(u64 args, u64 mach_nr, u64 fdt_addr,
u64 entry_point, u64 es_flag); u64 entry_point, u64 es_flag);
void armv8_el2_to_aarch32(u64 args, u64 mach_nr, u64 fdt_addr,
u64 entry_point);
void gic_init(void); void gic_init(void);
void gic_send_sgi(unsigned long sgino); void gic_send_sgi(unsigned long sgino);
void wait_for_wakeup(void); void wait_for_wakeup(void);