[PATCH stable 5.10 3/3] ARM: 9020/1: mm: use correct section size macro to describe the FDT virtual address

From: Florian Fainelli
Date: Sun May 09 2021 - 13:31:05 EST


From: Ard Biesheuvel <ardb@xxxxxxxxxx>

commit fc2933c133744305236793025b00c2f7d258b687 upstream

Commit

149a3ffe62b9dbc3 ("9012/1: move device tree mapping out of linear region")

created a permanent, read-only section mapping of the device tree blob
provided by the firmware, and added a set of macros to get the base and
size of the virtually mapped FDT based on the physical address. However,
while the mapping code uses the SECTION_SIZE macro correctly, the macros
use PMD_SIZE instead, which means something entirely different on ARM when
using short descriptors, and is therefore not the right quantity to use
here. So replace PMD_SIZE with SECTION_SIZE. While at it, change the names
of the macro and its parameter to clarify that it returns the virtual
address of the start of the FDT, based on the physical address in memory.

Tested-by: Joel Stanley <joel@xxxxxxxxx>
Tested-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
Signed-off-by: Ard Biesheuvel <ardb@xxxxxxxxxx>
Signed-off-by: Russell King <rmk+kernel@xxxxxxxxxxxxxxx>
Signed-off-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
---
arch/arm/include/asm/memory.h | 6 +++---
arch/arm/kernel/setup.c | 2 +-
2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/arch/arm/include/asm/memory.h b/arch/arm/include/asm/memory.h
index bb79e52aeb90..f717d7122d9d 100644
--- a/arch/arm/include/asm/memory.h
+++ b/arch/arm/include/asm/memory.h
@@ -68,8 +68,8 @@
#define XIP_VIRT_ADDR(physaddr) (MODULES_VADDR + ((physaddr) & 0x000fffff))

#define FDT_FIXED_BASE UL(0xff800000)
-#define FDT_FIXED_SIZE (2 * PMD_SIZE)
-#define FDT_VIRT_ADDR(physaddr) ((void *)(FDT_FIXED_BASE | (physaddr) % PMD_SIZE))
+#define FDT_FIXED_SIZE (2 * SECTION_SIZE)
+#define FDT_VIRT_BASE(physbase) ((void *)(FDT_FIXED_BASE | (physbase) % SECTION_SIZE))

#if !defined(CONFIG_SMP) && !defined(CONFIG_ARM_LPAE)
/*
@@ -111,7 +111,7 @@ extern unsigned long vectors_base;
#define MODULES_VADDR PAGE_OFFSET

#define XIP_VIRT_ADDR(physaddr) (physaddr)
-#define FDT_VIRT_ADDR(physaddr) ((void *)(physaddr))
+#define FDT_VIRT_BASE(physbase) ((void *)(physbase))

#endif /* !CONFIG_MMU */

diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c
index 694aa6b4bd03..f90479d8b50c 100644
--- a/arch/arm/kernel/setup.c
+++ b/arch/arm/kernel/setup.c
@@ -1086,7 +1086,7 @@ void __init setup_arch(char **cmdline_p)
void *atags_vaddr = NULL;

if (__atags_pointer)
- atags_vaddr = FDT_VIRT_ADDR(__atags_pointer);
+ atags_vaddr = FDT_VIRT_BASE(__atags_pointer);

setup_processor();
if (atags_vaddr) {
--
2.25.1