arm64/mm: Pass ttbr1 as a parameter to __enable_mmu()

In subsequent patches we'll use a transient pgd during the primary cpu's
boot process. To make this work while allowing secondary cpus to use the
swapper_pg_dir, we need to pass the relevant TTBR1 pgd as a parameter
to __enable_mmu().

This patch updates __enable__mmu() to take this as a parameter, updating
callsites to pass swapper_pg_dir for now.

There should be no functional change as a result of this patch.

Signed-off-by: Jun Yao <yaojun8558363@gmail.com>
Reviewed-by: James Morse <james.morse@arm.com>
[Mark: simplify assembly, clarify commit message]
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

arch/arm64/kernel/head.S

@@ -706,6 +706,7 @@ secondary_startup:
 	 * Common entry point for secondary CPUs.
 	 */
 	bl	__cpu_setup			// initialise processor
+	adrp	x1, swapper_pg_dir
 	bl	__enable_mmu
 	ldr	x8, =__secondary_switched
 	br	x8
@@ -748,6 +749,7 @@ ENDPROC(__secondary_switched)
  * Enable the MMU.
  *
  *  x0  = SCTLR_EL1 value for turning on the MMU.
+ *  x1  = TTBR1_EL1 value
  *
  * Returns to the caller via x30/lr. This requires the caller to be covered
  * by the .idmap.text section.
@@ -756,17 +758,16 @@ ENDPROC(__secondary_switched)
  * If it isn't, park the CPU
  */
 ENTRY(__enable_mmu)
-	mrs	x1, ID_AA64MMFR0_EL1
-	ubfx	x2, x1, #ID_AA64MMFR0_TGRAN_SHIFT, 4
+	mrs	x2, ID_AA64MMFR0_EL1
+	ubfx	x2, x2, #ID_AA64MMFR0_TGRAN_SHIFT, 4
 	cmp	x2, #ID_AA64MMFR0_TGRAN_SUPPORTED
 	b.ne	__no_granule_support
-	update_early_cpu_boot_status 0, x1, x2
-	adrp	x1, idmap_pg_dir
-	adrp	x2, swapper_pg_dir
-	phys_to_ttbr x3, x1
-	phys_to_ttbr x4, x2
-	msr	ttbr0_el1, x3			// load TTBR0
-	msr	ttbr1_el1, x4			// load TTBR1
+	update_early_cpu_boot_status 0, x2, x3
+	adrp	x2, idmap_pg_dir
+	phys_to_ttbr x1, x1
+	phys_to_ttbr x2, x2
+	msr	ttbr0_el1, x2			// load TTBR0
+	msr	ttbr1_el1, x1			// load TTBR1
 	isb
 	msr	sctlr_el1, x0
 	isb
@@ -823,6 +824,7 @@ __primary_switch:
 	mrs	x20, sctlr_el1			// preserve old SCTLR_EL1 value
 #endif
 
+	adrp	x1, swapper_pg_dir
 	bl	__enable_mmu
 #ifdef CONFIG_RELOCATABLE
 	bl	__relocate_kernel

arch/arm64/kernel/sleep.S

@@ -101,6 +101,7 @@ ENTRY(cpu_resume)
 	bl	el2_setup		// if in EL2 drop to EL1 cleanly
 	bl	__cpu_setup
 	/* enable the MMU early - so we can access sleep_save_stash by va */
+	adrp	x1, swapper_pg_dir
 	bl	__enable_mmu
 	ldr	x8, =_cpu_resume
 	br	x8