Patch "ARM: 9420/1: smp: Fix SMP for xip kernels" has been added to the 6.6-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    ARM: 9420/1: smp: Fix SMP for xip kernels

to the 6.6-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     arm-9420-1-smp-fix-smp-for-xip-kernels.patch
and it can be found in the queue-6.6 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 3a613fbb1743d1f501f4ee7ec5735f3b99ad4599
Author: Harith G <harith.g@xxxxxxxxxxxx>
Date:   Wed Sep 18 06:57:53 2024 +0100

    ARM: 9420/1: smp: Fix SMP for xip kernels
    
    [ Upstream commit 9e9b0cf9319b4db143014477b0bc4b39894248f1 ]
    
    Fix the physical address calculation of the following to get smp working
    on xip kernels.
    - secondary_data needed for secondary cpu bootup.
    - secondary_startup address passed through psci.
    - identity mapped code region needed for enabling mmu for secondary cpus.
    
    Signed-off-by: Harith George <harith.g@xxxxxxxxxxxx>
    Reviewed-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
    Signed-off-by: Russell King (Oracle) <rmk+kernel@xxxxxxxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S
index 28873cda464f5..f22c50d4bd417 100644
--- a/arch/arm/kernel/head.S
+++ b/arch/arm/kernel/head.S
@@ -411,7 +411,11 @@ ENTRY(secondary_startup)
 	/*
 	 * Use the page tables supplied from  __cpu_up.
 	 */
+#ifdef CONFIG_XIP_KERNEL
+	ldr	r3, =(secondary_data + PLAT_PHYS_OFFSET - PAGE_OFFSET)
+#else
 	adr_l	r3, secondary_data
+#endif
 	mov_l	r12, __secondary_switched
 	ldrd	r4, r5, [r3, #0]		@ get secondary_data.pgdir
 ARM_BE8(eor	r4, r4, r5)			@ Swap r5 and r4 in BE:
diff --git a/arch/arm/kernel/psci_smp.c b/arch/arm/kernel/psci_smp.c
index d4392e1774848..3bb0c4dcfc5c9 100644
--- a/arch/arm/kernel/psci_smp.c
+++ b/arch/arm/kernel/psci_smp.c
@@ -45,8 +45,15 @@ extern void secondary_startup(void);
 static int psci_boot_secondary(unsigned int cpu, struct task_struct *idle)
 {
 	if (psci_ops.cpu_on)
+#ifdef CONFIG_XIP_KERNEL
+		return psci_ops.cpu_on(cpu_logical_map(cpu),
+			((phys_addr_t)(&secondary_startup)
+			- XIP_VIRT_ADDR(CONFIG_XIP_PHYS_ADDR)
+			+ CONFIG_XIP_PHYS_ADDR));
+#else
 		return psci_ops.cpu_on(cpu_logical_map(cpu),
 					virt_to_idmap(&secondary_startup));
+#endif
 	return -ENODEV;
 }
 
diff --git a/arch/arm/mm/idmap.c b/arch/arm/mm/idmap.c
index 448e57c6f6534..4a833e89782aa 100644
--- a/arch/arm/mm/idmap.c
+++ b/arch/arm/mm/idmap.c
@@ -84,8 +84,15 @@ static void identity_mapping_add(pgd_t *pgd, const char *text_start,
 	unsigned long addr, end;
 	unsigned long next;
 
+#ifdef CONFIG_XIP_KERNEL
+	addr = (phys_addr_t)(text_start) - XIP_VIRT_ADDR(CONFIG_XIP_PHYS_ADDR)
+		+ CONFIG_XIP_PHYS_ADDR;
+	end = (phys_addr_t)(text_end) - XIP_VIRT_ADDR(CONFIG_XIP_PHYS_ADDR)
+		+ CONFIG_XIP_PHYS_ADDR;
+#else
 	addr = virt_to_idmap(text_start);
 	end = virt_to_idmap(text_end);
+#endif
 	pr_info("Setting up static identity map for 0x%lx - 0x%lx\n", addr, end);
 
 	prot |= PMD_TYPE_SECT | PMD_SECT_AP_WRITE | PMD_SECT_AF;