The GPIO reset driver supports reset and poweroff. But not all boards
support both. gpio_system_reset_check() must detect this situation.

Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

We should use sbi_timer_mdelay() instead of custom gpio_mdelay() in
the gpio reset driver.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Xiang W <wxjstz@126.com>

We now have frequency of the timer device provided by the platform
support so we can emulate desired delay using a loop where the number
loop iterations are based on timer frequency.

This patch provides sbi_timer_delay_loop() for above purpose.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Xiang W <wxjstz@126.com>

We now have frequency in timer device instance provided by platform
so let's print timer frequency as part of the boot prints.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Xiang W <wxjstz@126.com>

Generic mdelay() and udelay() functions can be provided by the
sbi_timer framework if timer frequency is available in the timer
instance provided by the platform support or timer driver.

This patch adds timer frequency (timer_freq) member in the
struct sbi_timer_device for above purpose.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Xiang W <wxjstz@126.com>

We add fdt_parse_timebase_frequency() function which can be used
by ACLINT mtimer driver and platform code to get timebase frequency.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Xiang W <wxjstz@126.com>

We use BUG() macro in csr_read_num(), csr_write_num(), and
misa_string() functions for unhandled cases.

Signed-off-by: Xiang W <wxjstz@126.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

Three macros are added. One is called BUG, which is used to put in an
unreachable branch. One is called BUG_ON, which is used to check bugs
and assert conditions are opposite. One is called SBI_ASSERT, used for
assertion checking.

Signed-off-by: Xiang W <wxjstz@126.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

The original version of ctz will cause an endless loop, if the parameter
passed in is 0. This commit fixes this bug.

Signed-off-by: Xiang W <wxjstz@126.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

One of the watchdogs in the D1 SoC provides a "soft reset" function,
which allows software to immediately reset the entire SoC. Add a driver
so it can implement the SBI system reset function.

Signed-off-by: Samuel Holland <samuel@sholland.org>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

In preparation for adding a new fdt_reset driver, ensure the existing
lists are sorted alphabetically.

Signed-off-by: Samuel Holland <samuel@sholland.org>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

sbi_platform_get_features_str() uses sbi_snprintf() to construct the
features_str. However, it passes the wrong length value (i.e., the nfstr),
which should be (nfstr-offset) as the starting point of str (i.e.,
features_str + offset) changes.

This commit also checks the return value of snprintf, and handles the
corner case that the string buffer is full.

Signed-off-by: Dong Du <Dd_nirvana@sjtu.edu.cn>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

As other exported fifo functions, we should check whether the fifo is
valid in sbi_fifo_is_empty and sbi_fifo_is_full. To this end, this patch
changes the retval from bool to int, and the two functions will return
SBI_EINVAL in the case the fifo is invalid.

Signed-off-by: Dong Du <Dd_nirvana@sjtu.edu.cn>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

Avoid getting messages from multiple harts (using dprintf and printf)
concurrently with a spinlock serializaing calls to sbi_dprintf(),
sbi_printf() and sbi_puts()

Signed-off-by: Dong Du <Dd_nirvana@sjtu.edu.cn>
Reviewed-by: Xiang W <wxjstz@126.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

Correcting the name of faults delegation CSR
%s/mfdeleg/medeleg

Signed-off-by: Rahul Pathak <rpathak@ventanamicro.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

It can be useful to make SBI v0.2 or newer ecalls from this payload
for testing purposes. To support this, convert the macros to use the
extension/function parameter convention.

Signed-off-by: Samuel Holland <samuel@sholland.org>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

commit 764a17d8 ("lib: sbi: Implement firmware counters") added
switch cases for CAUSE_LOAD_ACCESS and CAUSE_STORE_ACCESS. This caused
them to stop being redirected to U or S mode, as that is handled in the
default switch case. As a result, an error in userspace could cause the
system to hang. Fix this by allowing the acces fault case to fall
through to the default case.

Fixes: 764a17d8

 ("lib: sbi: Implement firmware counters")
Signed-off-by: Samuel Holland <samuel@sholland.org>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

In sbi_ecall_rfence_handler, it will compare the funcid with
REMOTE_HFENCE_GVMA and REMOTE_HFENCE_VVMA_ASID. Later it check
whether the misa includes H-extension. This checking is incomplete
which misses REMOTE_HFENCE_GVMA_VMID and REMOTE_HFENCE_VVMA.

Fix the issue by updating the checking range.

Signed-off-by: Dong Du <Dd_nirvana@sjtu.edu.cn>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

We simplify MTIMER synchronization as follows:

1) Detect MTIMER devices with unique (or non-shared) MTIME
   register at boot-time
2) Select first MTIMER device with no associated HART as our
   reference MTIMER device
3) Only synchronize MTIMER devices with unique (or non-shared)
   MTIME register using reference MTIMER device
4) Directly update the MTIME register at time of synchronization
   because MTIME is a read/write register.

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

We can have ACLINT MTIMER devices which only support 32-bit MMIO
accesses on RV64 system so this patch adds a boolean DT property
"mtimer,no-64bit-mmio" to detect this from MTIMER DT node.

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

The fdt_parse_aclint_node() is used to parse DT node for SiFive
CLINT, ACLINT MTIMER, and ACLINT MSWI devices.

The ACLINT MTIMER has undergone following changes:
1) MTIMER DT node now requires separate addresses in for MTIME
   register and MTIMECMPx registers in the reg DT property.
2) MTIMER DT node might have no interrupts-extended DT property
   when the MTIMER device has no associated HARTs (i.e. the
   MTIMER device has no MTIMECMPx registers)

This patch extends fdt_parse_aclint_node() to handle above
mentioned changes in ACLINT MTIMER DT bindings.

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

We add "index" parameter to fdt_get_node_addr_size() API so that
calling function can specify index of desired register set. This
will allow fdt_get_node_addr_size() to handle DT nodes with
multiple register sets.

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

We extend the ACLINT library to support separate base addresses
for MTIME and MTIMECMP registers.

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

The maximum address and size encoded in DT are 64-bit numbers, so we
should use uint64_t for 'addr' and 'size' in fdt_get_node_addr_size().

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

No need to compare characters when the count turns to 0.
Fix the issue in sbi_strncmp.

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

The generic GPIO reset driver has two entries in the match table:
"gpio-poweroff", "gpio-reset". Only the first entry is considered by
fdt_reset_init().

Define "gpio-poweroff" and "gpio-reset" as compatibility strings of two
separate reset drivers. They still can share code.

Fixes: e3d6919d

 ("lib: utils/reset: Add generic GPIO reset driver")
Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

The value of variable current_driver is unused. Remove the variable.

Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

Instruction TLB can fail to respect a non-global SFENCE thus we need to
flush the TLB using SFENCE.VMA x0, x0

See full description of CIP-1200 in Errata_FU740-C000_20210205 from
https://www.sifive.com/boards/hifive-unmatched



Signed-off-by: David Abdurachmanov <david.abdurachmanov@sifive.com>
Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>

The previous code uses _start as the load address, this default .entry is
the first segment, using _fw_start does not need to make this assumption.

Signed-off-by: Xiang W <wxjstz@126.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

When generating code with -mno-relax, GCC puts .option norelax in
the generated assembly, and so doesn’t bother passing on -mno-relax
to the assembler. This has the unfortunate effect that, when using
GCC to assemble hand-written assembly, -mno-relax does nothing,
and we have to pass -Wa,-mno-relax to manually forward it to the
assembler.

This is an old GCC bug that was fixed [1] recently. For the time
being, let's pass "-Wa,-mno-relax" to ASFLAGS for the GCC + LLD
combination to work, e.g.:

  $ make CC=riscv64-unknown-elf-gcc LLVM=1 PLATFORM=generic

[1] https://github.com/gcc-mirror/gcc/commit/3b0a7d624e64eeb81e4d5e8c62c46d86ef521857



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

Recent FW_PIC=y changes actually require toolchains with PIE support
and it is on by default. Existing doc uses a GNU bare-metal toolchain
as examples but it does not support PIE.

Replace references of bare-metal toolchain prefix with Linux toolchain
prefix everywhere in documentation.

Also indicate that "riscv64-unknown-freebsd-" as an alternative to
"riscv64-linux-" GNU toolchain.

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

FW_PIC=y is on by default, but the doc is missing when this was
introduced. Add some description for it.

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

This updates documentation to describe parameters passed to firmware
from previous booting stage, and corresponding address alignment
requirement.

This also fixes a typo in fw_dynamic.md (it's => its).

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

If the device tree is at an address that is not __SIZEOF_POINTER__
aligned, the fdt relocation code tries to align both source and
destination address to __SIZEOF_POINTER__ before the memory copy.
But such alignment can lead to unexpected results if either source
or destination address is not aligned.

In fact libfdt requires that the device tree must be at an 8-byte
aligned address. Hence remove the unhelpful alignment codes.

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

Clang provides a __builtin_offsetof which can be detected using
__has_builtin().

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

The fields are of type unsigned long and are not pointers. While this
happens to be the same for RV32/RV64, it is not correct when compiling
for a CHERI-RISC-V system where pointers are twice the size of long.

Signed-off-by: Alex Richardson <Alexander.Richardson@cl.cam.ac.uk>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

We add generic GPIO reset driver inspired from gpio-restart
and gpio-poweroff drivers of Linux kernel.

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

We add a minimal SiFive GPIO driver so that we can do GPIO based
system power-off and reset.

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

We add a simple FDT based GPIO framework which is built on top
of generic GPIO library. The phandle of FDT GPIO chip DT node
is treated as unique GPIO chip ID required by the generic GPIO
library. The FDT based GPIO chip drivers will be probed on-demand
from fdt_gpio_pin_get() called by the GPIO client drivers.

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

We add generic GPIO configuration library which is independent of
hardware description format (FDT or ACPI). The OpenSBI platform
support or GPIO drivers can register GPIO chip instances which
can be discovered and used by different GPIO clients. Each GPIO
chip instance has a unique ID which can be used by GPIO clients
to lookup GPIO chip instance.

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