On 5/6/25 11:24, Sughosh Ganu wrote:
U-Boot has support for both the 32-bit and 64-bit RiscV platforms. Set
the width of the phys_{addr,size}_t data types based on the register
size of the architecture.
Currently, even the 32-bit RiscV platforms have a 64-bit
phys_{addr,size}_t data types. This causes issues on the 32-bit
platforms, where the upper 32-bits of the variables of these types
can have junk data, and that can cause all kinds of side-effects.
How could it be that the upper 32-bit have junk data?
When we convert from a shorter variable the compiler should fill the
upper bits with zero.
This was discovered on the qemu Riscv 32-bit platform when the return
value of an LMB API was checked, and some LMB allocation that ought
not to have failed, was failing. The upper 32-bits of the address
variable contained garbage, resulting in failures.
Signed-off-by: Sughosh Ganu <sughosh.g...@linaro.org>
---
Note:
Although the LMB API cleanup series depends on this patch, I am
sending it separately so that it gets noticed by the RiscV
maintainers. Sometimes a patch may not get the required attention when
sent as part of another seemingly unrelated series.
arch/riscv/include/asm/types.h | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)
diff --git a/arch/riscv/include/asm/types.h b/arch/riscv/include/asm/types.h
index 49f7a5d6b3a..45d806c83eb 100644
--- a/arch/riscv/include/asm/types.h
+++ b/arch/riscv/include/asm/types.h
@@ -35,8 +35,13 @@ typedef u64 dma_addr_t;
typedef u32 dma_addr_t;
#endif
-typedef unsigned long long phys_addr_t;
-typedef unsigned long long phys_size_t;
+#ifdef CONFIG_PHYS_64BIT
+typedef u64 phys_addr_t;
+typedef u64 phys_size_t;
+#else
+typedef u32 phys_addr_t;
+typedef u32 phys_size_t;
This matches what has been done for ARM.
86c915628d58 ("riscv: Change phys_addr_t and phys_size_t to 64-bit")
changed the definition to 64bit phys addr_t to support the 34bit
physical addresses (similar to LPAE on arm32).
I don't think that we need 34bit support currently. But I would prefer
if we could find the root cause why the upper 32bit gets messed up as
this might point to a generic problem.
Best regards
Heinrich
+#endif
#endif /* __KERNEL__ */
