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| author | Hesham Almatary <hesham.almatary@cl.cam.ac.uk> | 2022-12-18 14:30:15 +0000 |
|---|---|---|
| committer | Hesham Almatary <hesham.almatary@cl.cam.ac.uk> | 2023-01-09 18:23:24 +0000 |
| commit | 6794f0166c231ca5c95bec9ab005eda496d5833d (patch) | |
| tree | 2cac09ea031fa3316d7fd5b0921463704ce8080f /user/bsps/bsps-riscv.rst | |
| parent | eng/vc-users.rst: Add commit message guidance (diff) | |
| download | rtems-docs-6794f0166c231ca5c95bec9ab005eda496d5833d.tar.bz2 | |
Docs: RISC-V Update rv64* BSPs to medany and 0x80000000 start address
Closes #4775
Diffstat (limited to '')
| -rw-r--r-- | user/bsps/bsps-riscv.rst | 27 |
1 files changed, 12 insertions, 15 deletions
diff --git a/user/bsps/bsps-riscv.rst b/user/bsps/bsps-riscv.rst index 2ef8327..5269462 100644 --- a/user/bsps/bsps-riscv.rst +++ b/user/bsps/bsps-riscv.rst @@ -8,7 +8,7 @@ riscv (RISC-V) riscv ===== -This BSP offers 15 variants: +This BSP offers 12 variants: * rv32i @@ -26,22 +26,20 @@ This BSP offers 15 variants: * rv64imac -* rv64imac_medany - * rv64imafd -* rv64imafd_medany - * rv64imafdc -* rv64imafdc_medany - * frdme310arty * mpfs64imafdc -Each variant corresponds to a GCC multilib. A particular variant reflects an -ISA with ABI and code model choice. +Each rv* variant corresponds to a GCC multilib. A particular variant reflects an +ISA with ABI and code model choice. All rv64 BSPs have medany code model by +default, while rv32 BSPs are medlow. The reason is that RV32 medlow can access +the entire 32-bit address space, while RV64 medlow can only access addresses +below 0x80000000. With RV64 medany, it's possible to perform accesses above +0x80000000. The BSP must be started im machine mode. @@ -94,8 +92,7 @@ configuration INI file. The ``waf`` defaults can be used to inspect the values. by default). ``RISCV_RAM_REGION_BEGIN`` - The begin of the RAM region for linker command file (default is 0x70000000 - for 64-bit with -mcmodel=medlow and 0x80000000 for all other). + The begin of the RAM region for linker command file (default is 0x80000000). ``RISCV_RAM_REGION_SIZE`` The size of the RAM region for linker command file (default 64MiB). @@ -145,13 +142,13 @@ QEMU ---- All of the BSP variants that start with rv can be run on QEMU's virt machine. -For instance, to run the ``rv64imafdc_medany`` BSP with the following -"config.ini" file: +For instance, to run the ``rv64imafdc`` BSP with the following +"config.ini" file. .. code-block:: none - [riscv/rv64imafdc_medany] + [riscv/rv64imafdc] -Run the following QEMU command: +Run the following QEMU command. .. code-block:: shell $ qemu-system-riscv64 -M virt -nographic -bios $RTEMS_EXE |