armv8: Support loading 32-bit OS in AArch32 execution state
To support loading a 32-bit OS, the execution state will change from
AArch64 to AArch32 when jumping to kernel.
The architecture information will be got through checking FIT image,
then U-Boot will load 32-bit OS or 64-bit OS automatically.
Signed-off-by: Ebony Zhu <ebony.zhu@nxp.com>
Signed-off-by: Alison Wang <alison.wang@nxp.com>
Signed-off-by: Chenhui Zhao <chenhui.zhao@nxp.com>
Reviewed-by: York Sun <york.sun@nxp.com>
diff --git a/arch/arm/include/asm/macro.h b/arch/arm/include/asm/macro.h
index 9bb0efa..2553e3e 100644
--- a/arch/arm/include/asm/macro.h
+++ b/arch/arm/include/asm/macro.h
@@ -8,6 +8,11 @@
#ifndef __ASM_ARM_MACRO_H__
#define __ASM_ARM_MACRO_H__
+
+#ifdef CONFIG_ARM64
+#include <asm/system.h>
+#endif
+
#ifdef __ASSEMBLY__
/*
@@ -135,13 +140,21 @@
#endif
.endm
-.macro armv8_switch_to_el2_m, xreg1
- /* 64bit EL2 | HCE | SMD | RES1 (Bits[5:4]) | Non-secure EL0/EL1 */
- mov \xreg1, #0x5b1
- msr scr_el3, \xreg1
+/*
+ * Switch from EL3 to EL2 for ARMv8
+ * @ep: kernel entry point
+ * @flag: The execution state flag for lower exception
+ * level, ES_TO_AARCH64 or ES_TO_AARCH32
+ * @tmp: temporary register
+ *
+ * For loading 32-bit OS, x1 is machine nr and x2 is ftaddr.
+ * For loading 64-bit OS, x0 is physical address to the FDT blob.
+ * They will be passed to the guest.
+ */
+.macro armv8_switch_to_el2_m, ep, flag, tmp
msr cptr_el3, xzr /* Disable coprocessor traps to EL3 */
- mov \xreg1, #0x33ff
- msr cptr_el2, \xreg1 /* Disable coprocessor traps to EL2 */
+ mov \tmp, #CPTR_EL2_RES1
+ msr cptr_el2, \tmp /* Disable coprocessor traps to EL2 */
/* Initialize Generic Timers */
msr cntvoff_el2, xzr
@@ -152,45 +165,90 @@
* and RES0 bits (31,30,27,26,24,21,20,17,15-13,10-6) +
* EE,WXN,I,SA,C,A,M to 0
*/
+ ldr \tmp, =(SCTLR_EL2_RES1 | SCTLR_EL2_EE_LE |\
+ SCTLR_EL2_WXN_DIS | SCTLR_EL2_ICACHE_DIS |\
+ SCTLR_EL2_SA_DIS | SCTLR_EL2_DCACHE_DIS |\
+ SCTLR_EL2_ALIGN_DIS | SCTLR_EL2_MMU_DIS)
+ msr sctlr_el2, \tmp
+
+ mov \tmp, sp
+ msr sp_el2, \tmp /* Migrate SP */
+ mrs \tmp, vbar_el3
+ msr vbar_el2, \tmp /* Migrate VBAR */
+
+ /* Check switch to AArch64 EL2 or AArch32 Hypervisor mode */
+ cmp \flag, #ES_TO_AARCH32
+ b.eq 1f
+
+ /*
+ * The next lower exception level is AArch64, 64bit EL2 | HCE |
+ * SMD | RES1 (Bits[5:4]) | Non-secure EL0/EL1.
+ */
- mov \xreg1, #0x0830
- movk \xreg1, #0x30C5, lsl #16
- msr sctlr_el2, \xreg1
+ ldr \tmp, =(SCR_EL3_RW_AARCH64 | SCR_EL3_HCE_EN |\
+ SCR_EL3_SMD_DIS | SCR_EL3_RES1 |\
+ SCR_EL3_NS_EN)
+ msr scr_el3, \tmp
/* Return to the EL2_SP2 mode from EL3 */
- mov \xreg1, sp
- msr sp_el2, \xreg1 /* Migrate SP */
- mrs \xreg1, vbar_el3
- msr vbar_el2, \xreg1 /* Migrate VBAR */
- mov \xreg1, #0x3c9
- msr spsr_el3, \xreg1 /* EL2_SP2 | D | A | I | F */
- msr elr_el3, lr
+ ldr \tmp, =(SPSR_EL_DEBUG_MASK | SPSR_EL_SERR_MASK |\
+ SPSR_EL_IRQ_MASK | SPSR_EL_FIQ_MASK |\
+ SPSR_EL_M_AARCH64 | SPSR_EL_M_EL2H)
+ msr spsr_el3, \tmp
+ msr elr_el3, \ep
+ eret
+
+1:
+ /*
+ * The next lower exception level is AArch32, 32bit EL2 | HCE |
+ * SMD | RES1 (Bits[5:4]) | Non-secure EL0/EL1.
+ */
+ ldr \tmp, =(SCR_EL3_RW_AARCH32 | SCR_EL3_HCE_EN |\
+ SCR_EL3_SMD_DIS | SCR_EL3_RES1 |\
+ SCR_EL3_NS_EN)
+ msr scr_el3, \tmp
+
+ /* Return to AArch32 Hypervisor mode */
+ ldr \tmp, =(SPSR_EL_END_LE | SPSR_EL_ASYN_MASK |\
+ SPSR_EL_IRQ_MASK | SPSR_EL_FIQ_MASK |\
+ SPSR_EL_T_A32 | SPSR_EL_M_AARCH32 |\
+ SPSR_EL_M_HYP)
+ msr spsr_el3, \tmp
+ msr elr_el3, \ep
eret
.endm
-.macro armv8_switch_to_el1_m, xreg1, xreg2
+/*
+ * Switch from EL2 to EL1 for ARMv8
+ * @ep: kernel entry point
+ * @flag: The execution state flag for lower exception
+ * level, ES_TO_AARCH64 or ES_TO_AARCH32
+ * @tmp: temporary register
+ *
+ * For loading 32-bit OS, x1 is machine nr and x2 is ftaddr.
+ * For loading 64-bit OS, x0 is physical address to the FDT blob.
+ * They will be passed to the guest.
+ */
+.macro armv8_switch_to_el1_m, ep, flag, tmp
/* Initialize Generic Timers */
- mrs \xreg1, cnthctl_el2
- orr \xreg1, \xreg1, #0x3 /* Enable EL1 access to timers */
- msr cnthctl_el2, \xreg1
+ mrs \tmp, cnthctl_el2
+ /* Enable EL1 access to timers */
+ orr \tmp, \tmp, #(CNTHCTL_EL2_EL1PCEN_EN |\
+ CNTHCTL_EL2_EL1PCTEN_EN)
+ msr cnthctl_el2, \tmp
msr cntvoff_el2, xzr
/* Initilize MPID/MPIDR registers */
- mrs \xreg1, midr_el1
- mrs \xreg2, mpidr_el1
- msr vpidr_el2, \xreg1
- msr vmpidr_el2, \xreg2
+ mrs \tmp, midr_el1
+ msr vpidr_el2, \tmp
+ mrs \tmp, mpidr_el1
+ msr vmpidr_el2, \tmp
/* Disable coprocessor traps */
- mov \xreg1, #0x33ff
- msr cptr_el2, \xreg1 /* Disable coprocessor traps to EL2 */
+ mov \tmp, #CPTR_EL2_RES1
+ msr cptr_el2, \tmp /* Disable coprocessor traps to EL2 */
msr hstr_el2, xzr /* Disable coprocessor traps to EL2 */
- mov \xreg1, #3 << 20
- msr cpacr_el1, \xreg1 /* Enable FP/SIMD at EL1 */
-
- /* Initialize HCR_EL2 */
- mov \xreg1, #(1 << 31) /* 64bit EL1 */
- orr \xreg1, \xreg1, #(1 << 29) /* Disable HVC */
- msr hcr_el2, \xreg1
+ mov \tmp, #CPACR_EL1_FPEN_EN
+ msr cpacr_el1, \tmp /* Enable FP/SIMD at EL1 */
/* SCTLR_EL1 initialization
*
@@ -199,18 +257,50 @@
* UCI,EE,EOE,WXN,nTWE,nTWI,UCT,DZE,I,UMA,SED,ITD,
* CP15BEN,SA0,SA,C,A,M to 0
*/
- mov \xreg1, #0x0800
- movk \xreg1, #0x30d0, lsl #16
- msr sctlr_el1, \xreg1
+ ldr \tmp, =(SCTLR_EL1_RES1 | SCTLR_EL1_UCI_DIS |\
+ SCTLR_EL1_EE_LE | SCTLR_EL1_WXN_DIS |\
+ SCTLR_EL1_NTWE_DIS | SCTLR_EL1_NTWI_DIS |\
+ SCTLR_EL1_UCT_DIS | SCTLR_EL1_DZE_DIS |\
+ SCTLR_EL1_ICACHE_DIS | SCTLR_EL1_UMA_DIS |\
+ SCTLR_EL1_SED_EN | SCTLR_EL1_ITD_EN |\
+ SCTLR_EL1_CP15BEN_DIS | SCTLR_EL1_SA0_DIS |\
+ SCTLR_EL1_SA_DIS | SCTLR_EL1_DCACHE_DIS |\
+ SCTLR_EL1_ALIGN_DIS | SCTLR_EL1_MMU_DIS)
+ msr sctlr_el1, \tmp
+
+ mov \tmp, sp
+ msr sp_el1, \tmp /* Migrate SP */
+ mrs \tmp, vbar_el2
+ msr vbar_el1, \tmp /* Migrate VBAR */
+
+ /* Check switch to AArch64 EL1 or AArch32 Supervisor mode */
+ cmp \flag, #ES_TO_AARCH32
+ b.eq 1f
+
+ /* Initialize HCR_EL2 */
+ ldr \tmp, =(HCR_EL2_RW_AARCH64 | HCR_EL2_HCD_DIS)
+ msr hcr_el2, \tmp
/* Return to the EL1_SP1 mode from EL2 */
- mov \xreg1, sp
- msr sp_el1, \xreg1 /* Migrate SP */
- mrs \xreg1, vbar_el2
- msr vbar_el1, \xreg1 /* Migrate VBAR */
- mov \xreg1, #0x3c5
- msr spsr_el2, \xreg1 /* EL1_SP1 | D | A | I | F */
- msr elr_el2, lr
+ ldr \tmp, =(SPSR_EL_DEBUG_MASK | SPSR_EL_SERR_MASK |\
+ SPSR_EL_IRQ_MASK | SPSR_EL_FIQ_MASK |\
+ SPSR_EL_M_AARCH64 | SPSR_EL_M_EL1H)
+ msr spsr_el2, \tmp
+ msr elr_el2, \ep
+ eret
+
+1:
+ /* Initialize HCR_EL2 */
+ ldr \tmp, =(HCR_EL2_RW_AARCH32 | HCR_EL2_HCD_DIS)
+ msr hcr_el2, \tmp
+
+ /* Return to AArch32 Supervisor mode from EL2 */
+ ldr \tmp, =(SPSR_EL_END_LE | SPSR_EL_ASYN_MASK |\
+ SPSR_EL_IRQ_MASK | SPSR_EL_FIQ_MASK |\
+ SPSR_EL_T_A32 | SPSR_EL_M_AARCH32 |\
+ SPSR_EL_M_SVC)
+ msr spsr_el2, \tmp
+ msr elr_el2, \ep
eret
.endm