The spec says sbi_system_suspend() will return SBI_ERR_INVALID_PARAM
when "sleep_type is reserved or is platform-specific and unimplemented"
and SBI_ERR_NOT_SUPPORTED when sleep_type "is not reserved and is
implemented, but the platform does not support it due to one or more
missing dependencies." Ensure SBI_ERR_INVALID_PARAM is returned for
reserved sleep types and that the system suspend driver can choose
which of the two error types to return itself by returning an error
from its check function rather than a boolean.
Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
With the introduction of the register_extensions callback the
range members (extid_start and extid_end) may now change and it
has become a bit subtle as to when a probe function should be
implemented. Document all the members and their relationship to
the register_extensions callback.
Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
When a probe implementation just returns zero for not available and
one for available then we don't need it, as the extension won't be
registered at all if it would return zero and the Base extension
probe function will already set out_val to 1 if not probe function
is implemented. Currently all probe functions only return zero or
one, so remove them all.
Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
When an extension implements a probe function it means there's a
chance that the extension is not available. Use this function in the
register_extensions callback to determine if the extension should be
registered at all. Where the probe implementation is simple, just
open code the check.
Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
The absence of a probe implementation means that the extension is
always available. Remove the implementation for the PMU extension,
which does no checking, and indeed even has a comment saying it's
always available.
Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
The vendor extension ID range is large, but at runtime at most
a single ID will be available. Narrow the range in the
register_extensions callback. After narrowing, we no longer
need to check that the extension ID is correct in the other
callbacks, as those callbacks will never be invoked with
anything other than the single ID.
Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Rather than registering all extensions on their behalf in
sbi_ecall_init(), introduce another extension callback and
invoke that instead. For now, implement each callback by
simply registering the extension, which means this patch
has no intended functional change. In later patches, extension
callbacks will be modified to choose when to register and to
possibly narrow the extension ID range prior to registering.
When an extension range needs to remove IDs, leaving gaps, then
multiple invocations of sbi_ecall_register_extension() may be
used. In summary, later patches for current extensions and the
introductions of future extensions will use the new callback to
ensure that only valid extension IDs from the initial range,
which are also available, will be registered.
Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
When the system-suspend-test property is present in the domain config
node as shown below, implement system suspend with a simple 5 second
delay followed by a WFI. This allows testing system suspend when the
low-level firmware doesn't support it.
/ {
chosen {
opensbi-domains {
compatible = "opensbi,domain,config";
system-suspend-test;
};
Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Fill the implementation of the system suspend ecall. A platform
implementation of the suspend callbacks is still required for this
to do anything.
Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Only privileged domains should be allowed to suspend the entire
system. Give the root domain this property by default and allow
other domains to be given the property by specifying it in the
DT.
Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Add the SUSP extension probe and ecall support, but for now the
system suspend function is just a stub.
Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
A coming patch can make use of a few internal hsm functions if
we export them.
Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
While non-retentive suspend is not allowed for M-mode, the comment
at the top of sbi_hsm_hart_suspend() implied suspend wasn't allowed
for M-mode at all. Move the comment above the mode check which is
inside a suspend type is non-retentive check.
Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
HSM functions define when SBI_ERR_INVALID_PARAM should be returned.
Ensure it's not used for reasons that don't meet the definitions by
using the catch-all code, SBI_ERR_FAILED, for those reasons instead.
Also, in one case sbi_hart_suspend() may have returned SBI_ERR_DENIED,
which isn't defined for that function at all. Use SBI_ERR_FAILED for
that case too.
Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
When a state change fails there's no need to restore the original
state as it remains the same.
Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Remove some redundant code by creating an invalid state detection
macro.
No functional change intended.
Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
sbi_domain_for_each() requires domidx_to_domain_table[] to be
null-terminated. Allocate one extra element which will always
be null.
Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
RISC-V doesn't generate exceptions on divide-by-zero, but the result,
all bits set, is not likely what people expect either. In all cases
where we divide by baudrate there's a chance it's zero (when the DT
it came from is "bad"). To avoid difficult to debug situations, leave
baudrate dependent registers alone when baudrate is zero, as, also in
all cases, it appears we can skip initialization of those registers
and still [hopefully] have a functioning UART.
Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
While it doesn't look like there are any current cases of using
uninitialized data, let's zero all the UART data members to be
safe. Zero may not actually be better than a random number in
some cases, so all structure members should still be validated
before use, but at least zero is usually easier to debug than
some random stack garbage...
Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Factor out the common code used by the fdt UART node parsers,
allowing us to drop duplicate code.
Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
printc would happily write to 'out' even when 'out_len' was zero,
potentially overflowing buffers. Rework printc to not do that and
also ensure the null byte is written at the last position when
necessary, as stated in the snprintf man page. Also, panic if
sprintf or snprintf are called with NULL output strings (except
the special case of snprintf having a NULL output string and
a zero output size, allowing it to be used to get the number of
characters that would have been written). Finally, rename a
goto label which clashed with 'out'.
Fixes: 9e8ff05cb6 ("Initial commit.")
Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
