To initialize PLIC in sane state, we should:
1. set maximum threshold value of M-mode PLIC contexts
2. set maximum threshold value of S-mode PLIC contexts
3. set irq priorities to miniumum

Fix the comment and initialize the threshold/priorities correctly.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Signed-off-by: Atish Patra <atish.patra@wdc.com>

As per the SBI specification, the return value in sbiret is undefined
if not explicitly described in the function. However, supervisor may
check this value by mistake and get a garbage value.

Initialize it to zero to avoid nasty supervisor bugs.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

We should should __builtin_ctzl() in pmp_get() instead of
custom ctz() function.

Signed-off-by: Li Jinpei <leekingp1994@163.com>
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

Instead of using loop to make "size" machine word aligned, we should
use bitwise ops.

Signed-off-by: Li Jinpei <leekingp1994@163.com>
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

Document that when U-Boot v2020.01 (or higher) is used as the payload,
we need adjust the instructions a little bit when testing OpenSBI with
QEMU 'sifive_u' machine.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

This adds sifive/fu540 specific QEMU run command.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

With QEMU v4.2 RISC-V changes to improve the emulation fidelity
of 'sifive_u' machine, OpenSBI v0.4 / U-Boot v2019.10 / Linux
kernel v5.3 images built for the SiFive HiFive Unleashed board
can be used out of the box without any special hack. Hence there
is no need for us to continue supporting such a special target in
OpenSBI. Going forward, sifive/fu540 platform can be used on both
real hardware and QEMU 'sifive_u' machine.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

On macOS the readlink command does not include a -f flag. Instead default
to using GNU readlink (which is often installed as greadlink).

Signed-off-by: Alex Richardson <Alexander.Richardson@cl.cam.ac.uk>
Signed-off-by: Anup Patel <anup.patel@wdc.com>

It was reported that tlb range flush is not working on fu540.
Only tlb full flush seems to work on fu540 probably due to some
hardware errata.

Set the tlb flush limit to zero so that all tlb flush requests
are converted to full flush.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

If a platform requires to perform a tlb full flush, they should set
the tlb_range_flush_limit value to zero. However, corresponding platform
API ignore the value and continue to return the default value.

Add a platform ops to retrieve platform specific tlb range flush limit.
The platform variable becomes redundant in presence of the platform ops.
Take this opportunity to remove the variable as well.

The default is still set to smallest page size in RISC-V (4KB), as there
is no way to figure out a best value for all platforms. Individual platform
should set it to the optimal value for their platform.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

In the QEMU [1] there was a change of the UART base addresses for
sifive_u machine to match the hardware. Make corresponding changes in
the opensbi for qemu/sifive_u platform.

[1] https://git.qemu.org/?p=qemu.git;a=commitdiff;h=4b55bc2b5f7ff065da5d2b813ee5153c598d3764



Signed-off-by: Nikita Ermakov <coffe92@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

This patch does minor typo fix in system reboot/shutdown names
in platform operations.

Signed-off-by: Jiuyang Liu (Sequencer) <liujiuyang1994@gmail.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Anup Patel <anup.patel@wdc.com>

This patch factor-out SBI base extension into its own source
for better modularity of SBI implementation.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

This patch factor-out SBI vendor extension into its own source
for better modularity of SBI implementation.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

This patch factor-out SBI replacement extensions (such as RFENCE,
IPI, and TIME) into its own source for better modularity of SBI
implementation.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

This patch factor-out SBI legacy extension into its own source
for better modularity of SBI implementation.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

This patch extends our SBI ecall implementation to allow
dynamic registration of various SBI extensions. Using this
dynamic registration we can break-up SBI ecall implementation
into multiple files and even register experimental/custom
SBI extensions from platform code.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

This patch adds generic and simple list handling APIs adapted
from Xvisor sources.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

Currently, the remote TLB management is initialized via IPI init
which is counter intuitive. This patch initializes remote TLB
management directly from init_coldboot() and init_warmboot()
after IPI init is done.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

This patch drops _fifo from the name of various sbi_tlb_fifo_xyz()
functions because all these functions deal with remote TLB managment
and FIFO is the per-HART data structure used internally by remote
TLB implementation.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

This patch introduces sbi_ipi_event_create/destroy() APIs and
struct sbi_ipi_event_ops for creating/destroying IPI events
at runtime based of event operations.

This new APIs will help platform code and utils code to create
custom IPI events which are not part of generic OpenSBI library.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

Instead of directly calling sbi_ipi_send_many(), we introduce
sbi_tlb_fifo_request() for halting a set of HARTs.

This way in future we can assign any IPI event number for remote
FENCE within sbi_tlb.c only.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

Instead of directly calling sbi_ipi_send_many(), we introduce
sbi_ipi_send_halt() for halting a set of HARTs.

This way in future we can assign any IPI event number for HART
halting within sbi_ipi.c only.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

Instead of directly calling sbi_ipi_send_many(), we introduce
sbi_ipi_send_smode() for injecting S-mode software interrupts.

This way in future we can assign any IPI event number for S-mode
IPIs within sbi_ipi.c only.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

The struct sbi_ipi_data is only used in sbi_ipi.c so move it
to sbi_ipi.c from sbi_ipi.h.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

This patch fixes a minor typo in comment for SBI_SCRATCH_SIZE define.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

This patch adds T-HEAD C910 to RV64 platform list in the binary
archive script.

Signed-off-by: Liu Yibin <yibin_liu@c-sky.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

Since all harts share the same plic/clint address now, setting
them during cold boot is just fine.

Signed-off-by: Liu Yibin <yibin_liu@c-sky.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

Since all harts share the same L2 cache now, there's
no need to Enable L2 cache in warm boot.

Signed-off-by: Liu Yibin <yibin_liu@c-sky.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

Move the .align directives after switching the section.  We want to align
the start of the current section, not the end of the previous section.
This also obsoletes the misguided workaround of disabling relaxation.

Signed-off-by: Andreas Schwab <schwab@suse.de>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

With U-Boot v2020.01, the SiFive FU540 DTB required by U-Boot is
embedded in U-Boot binary itself so we don't need to do anything
special for U-Boot v2020.01 as payload to OpenSBI firmware.

This patch updates SiFive FU540 documenation assuming we use
latest U-Boot v2020.01 release.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

T-head c910 is a generic FPGA platform so we cannot
define PMP configuration for it in OpenSBI because
PMP configuration tend to be SOC specific.

Signed-off-by: Liu Yibin <yibin_liu@c-sky.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

Add description of using OPENSBI_EXTERNAL_SBI_TYPES in external
firmware code base.

Signed-off-by: Abner Chang <abner.chang@hpe.com>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

Add OPENSBI_EXTERNAL_SBI_TYPES macro to allow external definitions of data
types and common macros. Also move some common definitions from sbi_bits.h to sbi_types.h.

Signed-off-by: Abner Chang <abner.chang@hpe.com>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

this is a stand-alone/baremetal application, therefore demanding
-ffreestanding would help it compile with hosted toolchains e.g. ( linux
toolchains ), it also ensures that it won't be using platform
optimizations like inlining mem* str* functions which gcc might decide
especially with wrapper string functions in opensbi code

Signed-off-by: Khem Raj <raj.khem@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

We add sbi_init_count() API which provides number of times a
given HART completed init sequence (warmboot/coldboot).

This will be very useful in debugging. With upcoming SBI HSM
extension, it will also help in implementing one-time init
code for each HART.

Signed-off-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

We should zero-out memory allocated from extra scratch space using
sbi_scratch_alloc_offset() API hence this patch. This will not
impact performance because we mostly allocate from extra scratch
space only at cold boot time.

Signed-off-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

We improve sbi_system_reboot() an sbi_system_shutdown() by:

1. Calling halt IPI to all harts (except current HART) before
   calling platform reboot/shutdown hook.
2. Calling sbi_exit() instead of sbi_hang() in-case platform
   reboot/shutdown hook failed.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

Instead of doing sbi_hang() we should do sbi_exit() upon
halt IPI.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

Currently, sbi_hart_wait_for_coldboot() leaves MIE.MSIP bit
set when it returns which is not correct because MIE.MSIP
should be left enabled only by sbi_ipi_init().

This patch does save/restore of MIE CSR to ensure that MIE
CSR is in original state after sbi_hart_wait_for_coldboot()
returns.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>