This patch moves all instruction encoding macros to
riscv_encoding.h.

Signed-off-by: Anup Patel <anup.patel@wdc.com>

The name CROSS_COMPILE is an industry standard used across
open-source project to specify cross-compiler prefix.

In fact, distro build systems such as buildroot and yocto
assume CROSS_COMPILE to be supported by projects added
as packages to these build systems.

This patch rename back CROSS_COMPILE_PREFIX to CROSS_COMPILE.

Signed-off-by: Anup Patel <anup.patel@wdc.com>

Some rewrite with a more formal style.

Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>

Clean was doing nothing. Fix it to remove all compiled files, leaving
only dependency files.

Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>

Make it clear what this environment variable defines and update
the README.md file to explain that.

Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>

Remove PLAT_<xyz> defines from platform and firmwares

The platform specific options will be PLATFORM_<xyz> and not
PLAT_<xyz> hence this patch fixes typo in top-level README.md.

Signed-off-by: Anup Patel <anup.patel@wdc.com>

The PLAT_HART_COUNT and PLAT_HART_STACK_SIZE are only used
by platform code so no need of exposing these to everyone
by adding it to platform-cppflags-y.

Signed-off-by: Anup Patel <anup.patel@wdc.com>

The hart_count and hart_stack_size information is already available
in "struct sbi_platform" so we use that instead of depending on
PLAT_HART_COUNT and PLAT_HART_STACK_SIZE.

Signed-off-by: Anup Patel <anup.patel@wdc.com>

We don't need a separate stack section for per-HART stack
instead we create per-HART stack at the end of firmware
(i.e. after _fw_end symbol).

Signed-off-by: Anup Patel <anup.patel@wdc.com>

The PLAT_NAME is used only in platform.c for all platforms hence
remove it.

Signed-off-by: Anup Patel <anup.patel@wdc.com>

Unleashed working 12 21

M mode is not expected to recieve any interrupts.
S mode interrupts shouldn't be enabled in M mode.

Signed-off-by: Atish Patra <atish.patra@wdc.com>

As of now, uboot doesn't have support for SMP.
Moreover, unleashed board has a E51 hart which
doesn't not support S mode.

We should only boot only 1 non-zero hart.

Signed-off-by: Atish Patra <atish.patra@wdc.com>

Pass S-Mode and M-mode context id separately to common warm init.

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

Unleashed doesn't have S mode for hart 0.
PLIC register base calculation is current wrong because of that.

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

Signed-off-by: Atish Patra <atish.patra@wdc.com>

Conditionnally delegate page fault exceptions from M mode to S mode
based on the platform features.

Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>

The math.h is not required anymore and it also gives
compile error for certain toolchains hence thsi patch
removes math.h include from kendryte/k210/sysctl.c.

Signed-off-by: Anup Patel <anup.patel@wdc.com>

The mideleg and medeleg are already programmed in delegate_traps()
so no need to set it here.

Any CSR setup in our reference firmware becomes a requirement
for bootloader linking to libsbi.a so we should have minimum
possible CSR setup in our reference firmware.

Signed-off-by: Anup Patel <anup.patel@wdc.com>

This patch reverts "Fix FDT relocation" because it breaks
fw_jump firmware.

Signed-off-by: Anup Patel <anup.patel@wdc.com>

The sbi_hart_switch_mode() will be used by CPU hotplug. This means
if we have prints in sbi_hart_switch_mode() then these prints will
mix with Linux prints.

Being a runtime firmware, we should be verbose only at coldboot
time and error situations.

Signed-off-by: Anup Patel <anup.patel@wdc.com>

commit d403c70f

 breaks Linux
booting because of fewer exceptions delegated to S-mode. This
patch fixes Linux booting by having all required exceptions
delegated to S-mode.

Signed-off-by: Anup Patel <anup.patel@wdc.com>

Avoid getting messages from multiple harts mingled into garbage text
with a spinlock serializing calls to sbi_puts() and sbi_printf().

Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>

Use functions defined in sbi/riscv_asm.h.

Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>

Use this helper instead of hardcoding csr_read(mhartid).

Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>

Cleanup sbi_hart_boot_nexti() code, adding messages for clarity and
rename the function to sbi_hart_switch_mode() to reflect what the
function actually does.

Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>

Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>

Booting now.

Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>

When S mode is not supported, simply clear mideleg and medeleg.
Otherwise, set delegation from M-mode to S-mode, removing the page
fault exceptions as those would not happen in M-mode.

Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>

Make it clear that the end of the FW execution was reached without the
hand being passed to any payload.

Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>

Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>

Also disable interrupts and exceptions delegation when clearing mie and
mip.

Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>

Or rather, disable it if FW_PAYLOAD_FDT_ADDR is not defined. This
correspond to cases where the underlying FW that loaded and started
opensbi did not provide any FDT. In such case, the platform code will
need to prepare one.

Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>

Allow a platform to report its supported features in more details.
The new features defined are:
* SBI_PLATFORM_HAS_PMP
* SBI_PLATFORM_HAS_SCOUNTEREN
* SBI_PLATFORM_HAS_MCOUNTEREN

In addition, define the macro SBI_PLATFORM_DEFAULT_FEATURES as the set
of features that are generally expected to be supported by a Linux
capable platform.

Operations touching the features controlled with these falgs are not
executed if the platform does not set the corresponding feature flags.

Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>

We should not jump to next stage if next mode (S-mode or U-mode)
is not supported by HART.

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

This patch renames "plat" to "platform" everywhere for better
readablility.

Signed-off-by: Anup Patel <anup.patel@wdc.com>

On QEMU Virt, max supported HARTs are 8 but number of HARTs
actually depend on "-smp" command-line parameter passed to
QEMU. This creates problems in sbi_hart_wake_coldboot_harts()
because when number of HARTs are less than 8.

To tackle this, we introduce a bitmap to track HARTs waiting
for coldboot to finish. We wake only those HARTs who have
set their bit in coldboot bitmap.

Signed-off-by: Anup Patel <anup.patel@wdc.com>

This patch renames "blob" to "firmware" everywhere for better
and intutive naming.

Signed-off-by: Anup Patel <anup@brainfault.org>

This patch removes unwanted sbi_printf() from
sbi_hart_wait_for_coldboot().

Signed-off-by: Anup Patel <anup.patel@wdc.com>