[PATCH 1/2] riscv: Fix XIP_FIXUP_FLASH_OFFSET

From: Myrtle Shah
Date: Thu Jan 20 2022 - 10:38:54 EST


There were several problems with the calculation. Not only was an 'and'
being computed into t1 but thrown away; but the 'and' itself would
cause problems if the granularity of the XIP physical address was less
than XIP_OFFSET - in my case I had the kernel image at 2MB in SPI flash.

I believe this approach is more generic.

Fixes: f9ace4ede49b ("riscv: remove .text section size limitation for XIP")

Signed-off-by: Myrtle Shah <gatecat@xxxxxx>
---
arch/riscv/kernel/head.S | 11 +++++------
1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S
index 604d60292dd8..b1ca65abeb1e 100644
--- a/arch/riscv/kernel/head.S
+++ b/arch/riscv/kernel/head.S
@@ -21,14 +21,13 @@
add \reg, \reg, t0
.endm
.macro XIP_FIXUP_FLASH_OFFSET reg
- la t1, __data_loc
- li t0, XIP_OFFSET_MASK
- and t1, t1, t0
- li t1, XIP_OFFSET
- sub t0, t0, t1
- sub \reg, \reg, t0
+ la t0, __data_loc
+ REG_L t1, _xip_phys_offset
+ sub \reg, \reg, t1
+ add \reg, \reg, t0
.endm
_xip_fixup: .dword CONFIG_PHYS_RAM_BASE - CONFIG_XIP_PHYS_ADDR - XIP_OFFSET
+_xip_phys_offset: .dword CONFIG_XIP_PHYS_ADDR + XIP_OFFSET
#else
.macro XIP_FIXUP_OFFSET reg
.endm
--
2.34.1