Commit graph

66 commits

Author SHA1 Message Date
Sean Anderson
404339759e riscv: Remove unnecessary instruction
The add instruction on risc-v can have any three sources and targets, so there
is no need for an intermediate mov.

Signed-off-by: Sean Anderson <seanga2@gmail.com>
Reviewed-by: Rick Chen <rick@andestech.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
2020-02-10 14:51:52 +08:00
Sean Anderson
fd1f6e9a0b riscv: Add option to print registers on exception
When debugging, it can be helpful to see more information about an
unhandled exception. This patch adds an option to view the registers at
the time of the trap, similar to the linux output on a kernel panic.

Signed-off-by: Sean Anderson <seanga2@gmail.com>
Reviewed-by: Rick Chen <rick@andestech.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
2020-02-10 14:51:08 +08:00
Sean Anderson
d9f1cee286 riscv: Fix breakage caused by linker relaxation
Due to the two-instruction sequence needed to access arbitrary memory
locations, the RISC-V linker aggressively optimises memory accesses and
jumps at link-time. This is called "linker relaxation," and is discussed
in this SiFive article
<https://www.sifive.com/blog/all-aboard-part-3-linker-relaxation-in-riscv-toolchain>.
One of the optimizations in place is to assume that the __global_pointer
symbol is placed in the gp register. To quote the article:

"...The magic __global_pointer$ symbol is defined to point 0x800 bytes
past the start of the .sdata section. The 0x800 magic number allows
signed 12-bit offsets from __global_pointer$ to address symbols at the
start of the .sdata section. The linker assumes that if this symbol is
defined, then the gp register contains that value, which it can then use
to relax accesses to global symbols within that 12-bit range. The
compiler treats the gp register as a constant so it doesn't need to be
saved or restored, which means it is generally only written by _start,
the ELF entry point."

However, U-Boot instead keeps the global data pointer in gp. This causes
memory accesses and jumps optimized to use the gp pointer to fail. To
fix this problem, we undefine the __global_pointer symbol.

Signed-off-by: Sean Anderson <seanga2@gmail.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Rick Chen <rick@andestech.com>
2020-02-10 14:50:53 +08:00
Simon Glass
941338725d common: Move relocate_code() to init.h
This is an init function so move it out of the common header. Avoid using
the typedef so that we don't have to include the global_data header file.

Also tidy up the function style in comments while we are here.

Signed-off-by: Simon Glass <sjg@chromium.org>
2020-01-17 13:26:49 -05:00
Lukas Auer
90ae281437 riscv: add option to wait for ack from secondary harts in smp functions
Add a wait option to smp_call_function() to wait for the secondary harts
to acknowledge the call-function request. The request is considered to
be acknowledged once each secondary hart has cleared the corresponding
IPI.

As part of the call-function request, the secondary harts invalidate the
instruction cache after clearing the IPI. This adds a delay between
acknowledgment (clear IPI) and fulfillment (call function) of the
request. We want to use the acknowledgment to be able to judge when the
request has been completed. Remove the delay by clearing the IPI after
cache invalidation and just before calling the function from the
request.

Signed-off-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: Rick Chen <rick@andestech.com>
Tested-by: Rick Chen <rick@andestech.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
2019-12-10 08:23:10 +08:00
Rick Chen
444c46413f riscv: Fix clear bss loop in the start-up code
For RV64, it will use sd instruction to clear t0
register, and the increament will be 8 bytes. So
if the difference between__bss_strat and __bss_end
was not 8 bytes aligned, the clear bss loop will
overflow and acks like system hang.

Signed-off-by: Rick Chen <rick@andestech.com>
Cc: KC Lin <kclin@andestech.com>
Cc: Alan Kao <alankao@andestech.com>
2019-12-10 08:23:10 +08:00
Rick Chen
8ba595b6bd riscv: ax25: cache: Add SPL_RISCV_MMODE for SPL
The mcache_ctl csr only can be manipulated in M mode.
Add SPL_RISCV_MMODE for U-Boot SPL to control cache
operation.

Signed-off-by: Rick Chen <rick@andestech.com>
Cc: KC Lin <kclin@andestech.com>
Cc: Alan Kao <alankao@andestech.com>
2019-12-10 08:23:10 +08:00
Rick Chen
ca06444aac riscv: ax25: add SPL support
The U-Boot SPL will boot in M mode and load the FIT image which
include OpenSBI and U-Boot proper images. After loading progress,
it will jump to OpenSBI first and then U-Boot proper which will
run in S mode.

Also remove V5L2_CACHE due to U-Boot SPL code size consideration.
Without this concern, it can be enable manually for performance.

Signed-off-by: Rick Chen <rick@andestech.com>
Cc: KC Lin <kclin@andestech.com>
Cc: Alan Kao <alankao@andestech.com>
2019-12-10 08:23:10 +08:00
Simon Glass
67c4e9f815 common: Move board_get_usable_ram_top() out of common.h
Move this function into init.h which seems to be designed for this sort
of thing. Also update the header to declare struct global_data so that it
can be included without global_data.h being needed.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@konsulko.com>
2019-12-02 18:25:04 -05:00
Simon Glass
36bf446b64 common: Move enable/disable_interrupts out of common.h
Move these two functions into the irq_funcs.h header file. Also move
interrupt_handler_t as this is used by the irq_install_handler() function.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@konsulko.com>
2019-12-02 18:25:01 -05:00
Simon Glass
1eb69ae498 common: Move ARM cache operations out of common.h
These functions are CPU-related and do not use driver model. Move them to
cpu_func.h

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
2019-12-02 18:24:58 -05:00
Simon Glass
9edefc2776 common: Move some cache and MMU functions out of common.h
These functions belong in cpu_func.h. Another option would be cache.h
but that code uses driver model and we have not moved these cache
functions to use driver model. Since they are CPU-related it seems
reasonable to put them here.

Move them over.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@konsulko.com>
2019-12-02 18:23:55 -05:00
Rick Chen
61ce84b2cf riscv: cache: use CCTL to flush d-cache
Use CCTL command to do d-cache write back
and invalidate instead of fence.

Signed-off-by: Rick Chen <rick@andestech.com>
Cc: KC Lin <kclin@andestech.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
2019-09-03 09:31:03 +08:00
Rick Chen
7045ed9f1a riscv: cache: Flush L2 cache before jump to linux
Flush and disable L2 cache in dcache_disable()
which will be called in cleanup_before_linux()
before jump to linux.

The sequence will be preferred as below:
L1 flush -> L1 disable -> L2 flush -> L2 disable

Signed-off-by: Rick Chen <rick@andestech.com>
Cc: KC Lin <kclin@andestech.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
2019-09-03 09:31:03 +08:00
Rick Chen
a8323d1816 riscv: ax25: add imply v5l2 cache controller
Select the v5l2 UCLASS_CACHE driver for ax25.

Signed-off-by: Rick Chen <rick@andestech.com>
Cc: KC Lin <kclin@andestech.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
2019-09-03 09:31:03 +08:00
Marcus Comstedt
f6cb427fdc riscv: update fix_rela_dyn
The addend is now added for RELOC_TYPE relocs.  Also, changed the loop
structure so that all the R_RISCV_RELATIVE relocs are not required to
be at the beginning of the list.

Signed-off-by: Marcus Comstedt <marcus@mc.pp.se>
Cc: Rick Chen <rick@andestech.com>
2019-09-03 09:30:41 +08:00
Lukas Auer
c7e1effb96 riscv: support SPL stack and global data relocation
To support relocation of the stack and global data on RISC-V, the
secondary harts must be notified of the change using IPIs. We can reuse
the hart relocation code for this purpose. It uses global data to store
the new stack pointer and global data pointer for the secondary harts.
This means that we cannot update the global data pointer of the main
hart in spl_relocate_stack_gd(), because the secondary harts have not
yet been relocated at this point. It is updated after the secondary
harts have been notified.

Signed-off-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
2019-08-26 16:07:42 +08:00
Lukas Auer
8c59f2023c riscv: add SPL support
U-Boot SPL on the generic RISC-V CPU supports two boot flows, directly
jumping to the image and via OpenSBI firmware. In the first case, both
U-Boot SPL and proper must be compiled to run in the same privilege
mode. Using OpenSBI firmware, U-Boot SPL must be compiled for machine
mode and U-Boot proper for supervisor mode.

To be able to use SPL, boards have to provide a supported SPL boot
device.

Signed-off-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
2019-08-26 16:07:42 +08:00
Lukas Auer
fbfd92bf9b riscv: add run mode configuration for SPL
U-Boot SPL can be run in a different privilege mode from U-Boot proper.
Add new configuration entries for SPL to allow the run mode to be
configured independently of U-Boot proper.

Extend all uses of the CONFIG_RISCV_SMODE and CONFIG_RISCV_MMODE
configuration symbols to also cover the SPL equivalents. Ensure that
files compatible with only one privilege mode are not included in builds
targeting an incompatible privilege mode.

Signed-off-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
2019-08-26 16:07:42 +08:00
Bin Meng
4d2583dba1 riscv: Access CSRs using CSR numbers
We should prefer accessing CSRs using their CSR numbers
because:
1. It compiles fine with older toolchains.
2. We can use latest CSR names in #define macro names of CSR
   numbers as-per RISC-V spec.
3. We can access newly added CSRs even if toolchain does not
   recognize newly added CSRs by name.

This commit is inspired from Linux kernel commit a3182c91ef4e
("RISC-V: Access CSRs using CSR numbers").

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Rick Chen <rick@andestech.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
2019-08-15 13:42:28 +08:00
Trevor Woerner
1001502545 CONFIG_SPL_SYS_[DI]CACHE_OFF: add
While converting CONFIG_SYS_[DI]CACHE_OFF to Kconfig, there are instances
where these configuration items are conditional on SPL. This commit adds SPL
variants of these configuration items, uses CONFIG_IS_ENABLED(), and updates
the configurations as required.

Acked-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Trevor Woerner <trevor@toganlabs.com>
[trini: Make the default depend on the setting for full U-Boot, update
more zynq hardware]
Signed-off-by: Tom Rini <trini@konsulko.com>
2019-05-18 08:15:35 -04:00
Rick Chen
f9281b8905 riscv: prior_stage_fdt_address should only be used when OF_PRIOR_STAGE is enabled
This patch will fix prior_stage_fdt_address write failure problem, when
AE350 boots from flash.

When AE350 boots from flash, prior_stage_fdt_address will be flash
address, we shall avoid it to be written.

Signed-off-by: Rick Chen <rick@andestech.com>
Cc: Greentime Hu <greentime@andestech.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
2019-05-09 16:46:46 +08:00
Rick Chen
bdce38965e riscv: Introduce CONFIG_XIP to support booting from flash
When U-Boot boots from flash, during the boot process,
hart_lottery and available_harts_lock variable addresses
point to flash which is not writable. This causes boot
failures on AE350. Introduce a config option CONFIG_XIP
to support such configuration.

Signed-off-by: Rick Chen <rick@andestech.com>
Cc: Greentime Hu <greentime@andestech.com>
Reviewed-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
2019-05-09 16:46:46 +08:00
Rick Chen
dda00ae4ef riscv: ax25: Andes specific cache shall only support in M-mode
Limit the cache configuration only can be supported in M mode.
It can not be manipulated in S mode.

Signed-off-by: Rick Chen <rick@andestech.com>
Cc: Greentime Hu <greentime@andestech.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
2019-04-08 09:45:08 +08:00
Rick Chen
8848474c5e riscv: ax25: Add platform-specific Kconfig options
Add ax25 RISC-V platform-specific Kconfig options,
to include CPU and timer drivers. Also disable
ATCPIT100 SoC timer and replace by PLMT.

Signed-off-by: Rick Chen <rick@andestech.com>
Cc: Greentime Hu <greentime@andestech.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
2019-04-08 09:45:08 +08:00
Lukas Auer
8ac39e2974 riscv: hang if relocation of secondary harts fails
Print an error message and hang if smp_call_function() returns an error,
indicating that relocation of the secondary harts has failed.

Signed-off-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
2019-04-08 09:44:26 +08:00
Lukas Auer
e043240252 riscv: do not rely on hart ID passed by previous boot stage
RISC-V U-Boot expects the hart ID to be passed to it via register a0 by
the previous boot stage. Machine mode firmware such as BBL and OpenSBI
do this when starting their payload (U-Boot) in supervisor mode. If
U-Boot is running in machine mode, this task must be handled by the boot
ROM. Explicitly populate register a0 with the hart ID from the mhartid
CSR to avoid possible problems on RISC-V processors with a boot ROM that
does not handle this task.

Suggested-by: Rick Chen <rick@andestech.com>
Signed-off-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Rick Chen <rick@andestech.com>
Tested-by: Rick Chen <rick@andestech.com>
2019-04-08 09:44:26 +08:00
Lukas Auer
3dea63c844 riscv: add support for multi-hart systems
On RISC-V, all harts boot independently. To be able to run on a
multi-hart system, U-Boot must be extended with the functionality to
manage all harts in the system. All harts entering U-Boot are registered
in the available_harts mask stored in global data. A hart lottery system
as used in the Linux kernel selects the hart U-Boot runs on. All other
harts are halted. U-Boot can delegate functions to them using
smp_call_function().

Every hart has a valid pointer to the global data structure and a 8KiB
stack by default. The stack size is set with CONFIG_STACK_SIZE_SHIFT.

Signed-off-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
2019-04-08 09:44:26 +08:00
Lukas Auer
1446b26f76 riscv: save hart ID in register tp instead of s0
The hart ID passed by the previous boot stage is currently stored in
register s0. If we divert the control flow inside a function, which is
required as part of multi-hart support, the function epilog may not be
called, clobbering register s0. Save the hart ID in the unallocatable
register tp instead to protect the hart ID.

Signed-off-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Rick Chen <rick@andestech.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
2019-04-08 09:44:26 +08:00
Lukas Auer
2503ccc55f riscv: delay initialization of caches and debug UART
Move the initialization of the caches and the debug UART until after
board_init_f_init_reserve. This is in preparation for SMP support, where
code prior to this point will be executed by all harts. This ensures
that initialization will only be performed once on the main hart running
U-Boot.

Signed-off-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
2019-04-08 09:44:26 +08:00
Anup Patel
26f4fd1cb4 riscv: generic: Ensure that U-Boot runs within 4GB for 64bit systems
On 64bit systems, the DRAM top can be easily beyond 4GB and U-Boot
DMA mapping APIs will generate DMA addresses beyond 4GB. This
breaks DMA programming in 32bit DMA capable devices (such as
Cadence MACB ethernet). For example, If DRAM is more then 2GB
on QEMU sifive_u machine then Cadence MACB ethernet stops working
for U-Boot because it is a 32bit DMA capable device.

To handle 32bit DMA capable devices on 64bit systems, we provide
custom implementation of board_get_usable_ram_top() which ensures
that usable ram top is not more then 4GB. This in-turn ensures
that U-Boot always runs within 4GB hence DMA addresses generated
by DMA mapping APIs will be within 4GB too.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Alexander Graf <agraf@suse.de>
Reviewed-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
2019-02-27 09:12:33 +08:00
Anup Patel
fdff1f96a6 riscv: Rename cpu/qemu to cpu/generic
The QEMU CPU support under arch/riscv is pretty much generic
and works fine for SiFive Unleashed as well. In fact, there
will be quite a few RISC-V SOCs for which QEMU CPU support
will work fine.

This patch renames cpu/qemu to cpu/generic to indicate the
above fact. If there are SOC specific errata workarounds
required in cpu/generic then those can be done at runtime
in cpu/generic based on CPU vendor specific DT compatible
string.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Alexander Graf <agraf@suse.de>
Reviewed-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
2019-02-27 09:12:33 +08:00
Lukas Auer
c9056653ec riscv: move the AX25-specific implementation of flush_dcache_all
The fence instruction is used to enforce device I/O and memory ordering
constraints in RISC-V. It can not be relied on to directly affect the
data cache on every CPU.
Andes' AX25 does not have a coherence agent. Its fence instruction
flushes the data cache and is used to keep data in the system coherent.
The implementation of flush_dcache_all in lib/cache.c is therefore
specific to the AX25. Move it into the AX25-specific cache.c in
cpu/ax25/.

This also adds a missing new line between flush_dcache_all and
flush_dcache_range in lib/cache.c.

Signed-off-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
2019-01-15 09:36:31 +08:00
Bin Meng
51ab4570f3 riscv: Save boot hart id to the global data
At present the hart id passed via a0 in the U-Boot entry is saved
to s0 at the beginning but does not preserve later. Save it to the
global data structure so that it can be used later.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: Anup Patel <anup@brainfault.org>
2018-12-18 09:56:27 +08:00
Bin Meng
10753ef8fd riscv: Return to previous privilege level after trap handling
At present the trap handler returns to hardcoded M-mode/S-mode.
Change to returning to previous privilege level instead.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: Anup Patel <anup@brainfault.org>
2018-12-18 09:56:27 +08:00
Bin Meng
496262cca6 riscv: Fix context restore before returning from trap handler
sp cannot be loaded before restoring other registers.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: Anup Patel <anup@brainfault.org>
2018-12-18 09:56:27 +08:00
Bin Meng
4b3f5ed5ac riscv: Move trap handler codes to mtrap.S
Currently the M-mode trap handler codes are in start.S. For future
extension, move them to a separate file mtrap.S.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: Anup Patel <anup@brainfault.org>
2018-12-18 09:56:27 +08:00
Bin Meng
485e822346 riscv: Do some basic architecture level cpu initialization
In arch_cpu_init_dm() do some basic architecture level cpu
initialization, like FPU enable, etc.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: Anup Patel <anup@brainfault.org>
2018-12-18 09:56:27 +08:00
Bin Meng
aef59e5cc4 riscv: Update supports_extension() to use desc from cpu driver
This updates supports_extension() implementation to use the desc
string from the cpu driver whenever possible, which avoids the
reading of misa CSR for S-mode U-Boot.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: Anup Patel <anup@brainfault.org>
2018-12-18 09:56:27 +08:00
Bin Meng
3c276b2703 riscv: Remove non-DM version of print_cpuinfo()
With DM CPU driver, the non-DM version of print_cpuinfo() is no
longer needed.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: Anup Patel <anup@brainfault.org>
2018-12-18 09:56:27 +08:00
Bin Meng
39cad5bc0b riscv: Probe cpus during boot
This calls cpu_probe_all() to probe all available cpus.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: Anup Patel <anup@brainfault.org>
2018-12-18 09:56:27 +08:00
Bin Meng
84304d4866 riscv: qemu: Add platform-specific Kconfig options
Add the QEMU RISC-V platform-specific Kconfig options, to include
CPU and timer drivers.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: Anup Patel <anup@brainfault.org>
2018-12-18 09:56:27 +08:00
Bin Meng
44fe795c14 riscv: ax25: Hide the ax25-specific Kconfig option
There is no need to expose RISCV_NDS to the Kconfig menu as it is
an ax25-specific option. Introduce a dedicated Kconfig option for
the cache ops of ax25 platform and use that to guard the cache ops.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: Rick Chen <rick@andestech.com>
2018-12-18 09:56:26 +08:00
Bin Meng
27dc2c130e riscv: qemu: Create a simple-bus driver for the soc node
To enumerate devices on the /soc/ node, create a "simple-bus"
driver to match "riscv-virtio-soc".

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: Anup Patel <anup@brainfault.org>
2018-12-18 09:56:26 +08:00
Rick Chen
48cbf62460 riscv: ax25-ae350: Pass dtb address to u-boot with a1 register
ax25-ae350 use CONFIG_OF_BOARD via a2 and CONFIG_SYS_SDRAM_BASE
to boot from ram which allow the board to override the fdt
address originally.

But after this patch
riscv: save hart ID and device tree passed by prior boot stage
It provide prior_stage_fdt_address which offer a temporary
memory address to keep the dtb address passing from loader(gdb)
to u-boot with a1.

So passing via a2 and CONFIG_SYS_SDRAM_BASE is redundant and
can be removed. And it also somehow may corrupted BBL if it
was be arranged in CONFIG_SYS_SDRAM_BASE.

In board_fdt_blob_setup()
When boting from ram:
prior_stage_fdt_address will be use to reserved dtb temporarily.

When booting from ROM:
dtb will be pre-burned in CONFIG_SYS_FDT_BASE, if it is flash base.
Or CONFIG_SYS_FDT_BASE maybe a memory map space (NOT RAM or ROM)
which is provided by HW.

Signed-off-by: Rick Chen <rick@andestech.com>
Cc: Greentime Hu <greentime@andestech.com>
2018-12-05 14:14:16 +08:00
Anup Patel
d2db2a8fa4 riscv: Add kconfig option to run U-Boot in S-mode
This patch adds kconfig option RISCV_SMODE to run U-Boot in
S-mode. When this opition is enabled we use s<xyz> CSRs instead
of m<xyz> CSRs.

It is important to note that there is no equivalent S-mode CSR
for misa and mhartid CSRs so we expect M-mode runtime firmware
(BBL or equivalent) to emulate misa and mhartid CSR read.

In-future, we will have more patches to avoid accessing misa and
mhartid CSRs from S-mode.

Signed-off-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
2018-12-05 14:13:53 +08:00
Rick Chen
52923c6db7 riscv: cache: Implement i/dcache [status, enable, disable]
AndeStar RISC-V(V5) provide mcache_ctl register which
can configure I/D cache as enabled or disabled.

This CSR will be encapsulated by CONFIG_RISCV_NDS.
If you want to configure cache on AndeStar V5
AE350 platform. YOu can enable [*] AndeStar V5 ISA support
by make menuconfig.

This approach also provide the expansion when the
vender specific features are going to join in.

Signed-off-by: Rick Chen <rick@andestech.com>
Cc: Greentime Hu <greentime@andestech.com>
2018-11-26 13:58:01 +08:00
Lukas Auer
5d8b2e7711 riscv: save hart ID and device tree passed by prior boot stage
Store the hart ID and device tree passed by the prior boot stage (in a0
and a1) in registers s0 and s1. Replace one use of s1 in start.S to
avoid overwriting it.

The device tree is also stored in memory to make it available to U-Boot
with the configuration CONFIG_OF_PRIOR_STAGE.

Signed-off-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Rick Chen <rick@andestech.com>
2018-11-26 13:57:32 +08:00
Lukas Auer
31f9058994 riscv: do not blindly modify the mstatus CSR
The mstatus CSR includes WPRI (writes preserve values, reads ignore
values) fields and must therefore not be set to zero without preserving
these fields. It is not apparent why mstatus is set to zero here since
it is not required for U-Boot to run. Remove it.

This instruction and others encode zero as an immediate.  RISC-V has the
zero register for this purpose. Replace the immediates with the zero
register.

Signed-off-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Rick Chen <rick@andestech.com>
2018-11-26 13:57:32 +08:00
Lukas Auer
8bfa231cc6 riscv: remove unused labels in start.S
The labels nmi_vector, trap_vector and handle_reset in start.S are not
used for RISC-V. Remove them.

Signed-off-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
2018-11-26 13:57:32 +08:00