diff options
| author | Vitaly Wool <vitaly.wool@konsulko.com> | 2021-04-13 02:35:14 -0400 |
|---|---|---|
| committer | Palmer Dabbelt <palmerdabbelt@google.com> | 2021-04-26 08:31:28 -0700 |
| commit | 44c922572952d89a1ed15764f2b373ba62692865 (patch) | |
| tree | d222695f2d1e336a1be86c47be29aade75af7b1f /arch/riscv/include/asm/page.h | |
| parent | 5640975003d0234da08559677e22ec25b9cb3267 (diff) | |
RISC-V: enable XIP
Introduce XIP (eXecute In Place) support for RISC-V platforms.
It allows code to be executed directly from non-volatile storage
directly addressable by the CPU, such as QSPI NOR flash which can
be found on many RISC-V platforms. This makes way for significant
optimization of RAM footprint. The XIP kernel is not compressed
since it has to run directly from flash, so it will occupy more
space on the non-volatile storage. The physical flash address used
to link the kernel object files and for storing it has to be known
at compile time and is represented by a Kconfig option.
XIP on RISC-V will for the time being only work on MMU-enabled
kernels.
Signed-off-by: Vitaly Wool <vitaly.wool@konsulko.com>
[Alex: Rebase on top of "Move kernel mapping outside the linear mapping" ]
Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
[Palmer: disable XIP for allyesconfig]
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Diffstat (limited to 'arch/riscv/include/asm/page.h')
| -rw-r--r-- | arch/riscv/include/asm/page.h | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/arch/riscv/include/asm/page.h b/arch/riscv/include/asm/page.h index f64b61296c0c..e280ba60cb34 100644 --- a/arch/riscv/include/asm/page.h +++ b/arch/riscv/include/asm/page.h @@ -93,6 +93,9 @@ extern unsigned long va_pa_offset; #ifdef CONFIG_64BIT extern unsigned long va_kernel_pa_offset; #endif +#ifdef CONFIG_XIP_KERNEL +extern unsigned long va_kernel_xip_pa_offset; +#endif extern unsigned long pfn_base; #define ARCH_PFN_OFFSET (pfn_base) #else @@ -107,11 +110,29 @@ extern unsigned long pfn_base; extern unsigned long kernel_virt_addr; #define linear_mapping_pa_to_va(x) ((void *)((unsigned long)(x) + va_pa_offset)) +#ifdef CONFIG_XIP_KERNEL +#define kernel_mapping_pa_to_va(y) ({ \ + unsigned long _y = y; \ + (_y >= CONFIG_PHYS_RAM_BASE) ? \ + (void *)((unsigned long)(_y) + va_kernel_pa_offset + XIP_OFFSET) : \ + (void *)((unsigned long)(_y) + va_kernel_xip_pa_offset); \ + }) +#else #define kernel_mapping_pa_to_va(x) ((void *)((unsigned long)(x) + va_kernel_pa_offset)) +#endif #define __pa_to_va_nodebug(x) linear_mapping_pa_to_va(x) #define linear_mapping_va_to_pa(x) ((unsigned long)(x) - va_pa_offset) +#ifdef CONFIG_XIP_KERNEL +#define kernel_mapping_va_to_pa(y) ({ \ + unsigned long _y = y; \ + (_y < kernel_virt_addr + XIP_OFFSET) ? \ + ((unsigned long)(_y) - va_kernel_xip_pa_offset) : \ + ((unsigned long)(_y) - va_kernel_pa_offset - XIP_OFFSET); \ + }) +#else #define kernel_mapping_va_to_pa(x) ((unsigned long)(x) - va_kernel_pa_offset) +#endif #define __va_to_pa_nodebug(x) ({ \ unsigned long _x = x; \ (_x < kernel_virt_addr) ? \ |