[PATCH AUTOSEL 6.7 10/13] riscv: Make XIP bootable again

Sasha Levin
2024-01-24T14:28:49Z

From: Frederik Haxel <haxel@fzi.de>

[ Upstream commit 66f1e68093979816a23412a3fad066f5bcbc0360 ]

Currently, the XIP kernel seems to fail to boot due to missing
XIP_FIXUP and a wrong page_offset value. A superfluous XIP_FIXUP
has also been removed.

Signed-off-by: Frederik Haxel <haxel@fzi.de>
Link: https://lore.kernel.org/r/20231212130116.848530-2-haxel@fzi.de
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/riscv/kernel/head.S | 1 +
arch/riscv/mm/init.c | 8 ++++++--
2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S
index 76ace1e0b46f..663881785b2b 100644
--- a/arch/riscv/kernel/head.S
+++ b/arch/riscv/kernel/head.S
@@ -89,6 +89,7 @@ relocate_enable_mmu:
/* Compute satp for kernel page tables, but don't load it yet */
srl a2, a0, PAGE_SHIFT
la a1, satp_mode
+ XIP_FIXUP_OFFSET a1
REG_L a1, 0(a1)
or a2, a2, a1

diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
index 2e011cbddf3a..a65937336cdc 100644
--- a/arch/riscv/mm/init.c
+++ b/arch/riscv/mm/init.c
@@ -174,6 +174,9 @@ void __init mem_init(void)

/* Limit the memory size via mem. */
static phys_addr_t memory_limit;
+#ifdef CONFIG_XIP_KERNEL
+#define memory_limit (*(phys_addr_t *)XIP_FIXUP(&memory_limit))
+#endif /* CONFIG_XIP_KERNEL */

static int __init early_mem(char *p)
{
@@ -952,7 +955,7 @@ static void __init create_fdt_early_page_table(uintptr_t fix_fdt_va,
* setup_vm_final installs the linear mapping. For 32-bit kernel, as the
* kernel is mapped in the linear mapping, that makes no difference.
*/
- dtb_early_va = kernel_mapping_pa_to_va(XIP_FIXUP(dtb_pa));
+ dtb_early_va = kernel_mapping_pa_to_va(dtb_pa);
#endif

dtb_early_pa = dtb_pa;
@@ -1055,9 +1058,9 @@ asmlinkage void __init setup_vm(uintptr_t dtb_pa)
#endif

kernel_map.virt_addr = KERNEL_LINK_ADDR + kernel_map.virt_offset;
- kernel_map.page_offset = _AC(CONFIG_PAGE_OFFSET, UL);

#ifdef CONFIG_XIP_KERNEL
+ kernel_map.page_offset = PAGE_OFFSET_L3;
kernel_map.xiprom = (uintptr_t)CONFIG_XIP_PHYS_ADDR;
kernel_map.xiprom_sz = (uintptr_t)(&_exiprom) - (uintptr_t)(&_xiprom);

@@ -1067,6 +1070,7 @@ asmlinkage void __init setup_vm(uintptr_t dtb_pa)

kernel_map.va_kernel_xip_pa_offset = kernel_map.virt_addr - kernel_map.xiprom;
#else
+ kernel_map.page_offset = _AC(CONFIG_PAGE_OFFSET, UL);
kernel_map.phys_addr = (uintptr_t)(&_start);
kernel_map.size = (uintptr_t)(&_end) - kernel_map.phys_addr;
#endif
--
2.43.0