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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
This is now deprecated and no board is using it. Drop it.
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Signed-off-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
The machine trap-vector base address (mtvec) must be aligned on a 4-byte
boundary. Add the necessary align directive to trap_entry.
This patch also removes the global directive for trap_entry, which is
not required.
Signed-off-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
start.S uses both tabs and spaces after instructions. Fix this by only
using tabs after instructions.
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>
We don't have a reset method on any RISC-V board yet. Instead of
adding the same 'unsupported' message for each CPU variant it might
make more sense to add a generic do_reset function for all CPU
variants to lib/, similar to the one for ARM (arch/arm/lib/reset.c).
Suggested-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
This adds QEMU RISC-V 'virt' board target support, with the hope of
helping people easily test U-Boot on RISC-V.
The QEMU virt machine models a generic RISC-V virtual machine with
support for the VirtIO standard networking and block storage devices.
It has CLINT, PLIC, 16550A UART devices in addition to VirtIO and
it also uses device-tree to pass configuration information to guest
software. It implements RISC-V privileged architecture spec v1.10.
Both 32-bit and 64-bit builds are supported. Support is pretty much
preliminary, only booting to U-Boot shell with the UART driver on
a single core. Booting Linux is not supported yet.
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Currently start.S is inside arch/riscv/cpu/ax25/, but it can be
common for all RISC-V targets.
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
This adds a helper routine to print CPU information. Currently
it prints all the instruction set extensions that the processor
core supports.
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
There are several coding style issues in the linker script. Fix them.
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
The linker script can be shared by all RISC-V targets. Move it to
a common place.
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
When we build with -fdata-sections we may end up with bss subsections. Our
linker script explicitly lists only a single consecutive bss section though.
Adapt the statement to also include subsections.
Signed-off-by: Alexander Graf <agraf@suse.de>
Some times gcc may generate data that is then used within code that may
be part of an efi runtime section. That data could be jump tables,
constants or strings.
In order to make sure we catch these, we need to ensure that gcc emits
them into a section that we can relocate together with all the other
efi runtime bits. This only works if the -ffunction-sections and
-fdata-sections flags are passed and the efi runtime functions are
in a section that starts with ".text".
Up to now we had all efi runtime bits in sections that did not
interfere with the normal section naming scheme, but this forces
us to do so. Hence we need to move the efi_loader text/data/rodata
sections before the global *(.text*) catch-all section.
With this patch in place, we should hopefully have an easier time
to extend the efi runtime functionality in the future.
Signed-off-by: Alexander Graf <agraf@suse.de>
[agraf: Fix x86_64 breakage]
Andes has rearranged the product combinations.
nx25 and ax25 both are RISC-V architecture cpu core.
But ax25 has MMU unit inside, and nx25 is not.
Cpu nx25 and platform ae250 are arranged in pairs.
Cpu ax25 and platform ae350 are arranged in pairs.
This patch will rename
nx25 as ax25
ae250 as ae350
nx25-ae250 as ax25-ae350
including filename, variable, string and definition.
Then u-boot can boot linux kernel in ae350
platform reasonably.
Signed-off-by: Rick Chen <rick@andestech.com>
Signed-off-by: Rick Chen <rickchen36@gmail.com>
Cc: Greentime Hu <green.hu@gmail.com>
We have almost all pieces needed to support RISC-V UEFI binaries in place already.
The only missing piece are ELF relocations for runtime code and
data.
This patch adds respective support in the linker script and the runtime
relocation code. It also allows users to enable the EFI_LOADER configuration
switch on RISC-V platforms.
Signed-off-by: Alexander Graf <agraf@suse.de>
When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from. So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry. Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.
In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.
This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents. There's also a few places where I found we did not have a tag
and have introduced one.
Signed-off-by: Tom Rini <trini@konsulko.com>
Enable CONFIG_OF_BOAD to support delivery dtb to u-boot
at run time instead of embedded.
There are two methods to delivery dtb.
1 Pass from loader:
When u-boot boot from RAM, gdb or loader can pass dtb
via a2 to u-boot dynamically. Of course gdb or loader
shall be in charge of dtb delivery.
2 Configure CONFIG_SYS_FDT_BASE:
It can be configured as RAM or ROM base statically,
no mater u-boot boot from RAM or ROM.
If it was configured as ROM base, dtb can be burned
into ROM(spi flash) by spi driver.
Meanwhile remove CONFIG_SKIP_LOWLEVEL_INIT which is
useless in nx25-ae250 configuration.
Signed-off-by: Rick Chen <rick@andestech.com>
Signed-off-by: Rick Chen <rickchen36@gmail.com>
Cc: Greentime Hu <green.hu@gmail.com>
Add Andes nx25 cpu core (called AndesStar V5) to support RISC-V arch
Verifications:
1. startup and relocation ok.
2. boot from rom or ram both ok.
2. timer driver ok.
3. uart driver ok
4. mmc driver ok
5. spi driver ok.
6. 32/64 bit both ok.
Detail verification message please see doc/README.ae250.
Signed-off-by: Rick Chen <rick@andestech.com>
Signed-off-by: Rick Chen <rickchen36@gmail.com>
Signed-off-by: Greentime Hu <green.hu@gmail.com>
Cc: Padmarao Begari <Padmarao.Begari@microsemi.com>
