Enable OpenSBI to support position independent execution. Because the
position independent code will cause an additional GOT reference when
accessing the global variables, it will reduce performance a bit. Therefore,
the position independent execution is disabled by default. Users can
through specifying "FW_PIC=y" on the make command to enable this feature.

In theory, after enabling position-independent execution, the OpenSBI
can run at arbitrary address with appropriate alignment. Therefore, the
original relocation mechanism will be skipped. In other words, OpenSBI will
directly run at the load address without any code movement.

Signed-off-by: Vincent Chen <vincent.chen@sifive.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

When OpenSBI is compiled as fPIE mode, the assembler will translate "la"
to GOT reference pattern. It will cause to cost an additional load
instruction when obtaining the symbol address. However, if the symbol
locates within the positive or negative 2GB region, we can use "lla"
instead of "la" to avoid unneeded GOT references. This patch assumes that
the OpenSBI image excluding the payload does not exceed 2GB. Based on
this assumption, all "la" instructions are replaced by "lla" to avoid
performance degradation when compiling as fPIE mode.

Signed-off-by: Vincent Chen <vincent.chen@sifive.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

The SBI function IDs for RFENCE extension must match the SBI specification.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

The sbi_platform_ipi_clear() called from wait_for_coldboot() and
sbi_hsm_hart_wait() is redundant because IPI will be automatically
cleared by sbi_platform_ipi_init() called from sbi_ipi_init().

Further, wait_for_coldboot() is common for warm startup and warm
resume path so the sbi_platform_ipi_clear() called in warm resume
path cause resuming HART to miss an IPI injected other HART to
wakeup the HART.

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

The OpenSBI SBI implementation is now compliant with latest draft
SBI v0.3 specification so let's upgrade SBI implementation version.

This will also help HSM suspend function detection in S-mode because
HSM suspend function is only present when HSM extension is present
and SBI implementation version is 0.3 (or higher).

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

This patch implements the SBI HSM suspend function. Using this
new SBI call, the S-mode software can put calling HART in platform
specific suspend (i.e. low-power) state. For a successful retentive
suspend, the SBI call will return without errors upon resuming
whereas for a successful non-retentive suspend, the SBI call will
resume from a user provided resume address.

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

We add hart_suspend() callback in platform operations which will
be used by HSM implementation to enter retentive or non-retentive
suspend state.

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

We add sbi_hart_reinit() function which will re-initialize HART CSRs
assuming HART features are already detected. This new function will
be useful in re-initializing HART after it resumes from HSM SUSPENDED
state.

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

This patch adds SBI HSM suspend related defines to ecall interface
header.

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

The sbi_hsm_hart_start() and sbi_hsm_hart_stop() functions should
only return error codes as defined by the SBI specification.

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

The sbi_hsm_hart_started() function is only used by sbi_hsm_hart_stop()
for checking state of calling HART and current domain assignment.

The atomic_cmpxchg() called by sbi_hsm_hart_stop() will check state of
calling hart anyway and domain assignment can be checked by other domain
function such as sbi_domain_is_assigned_hart().

This means sbi_hsm_hart_started() is redundant and can be removed.

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

A hart can take interrupt in the new HSM states introduced by the
SBI HSM suspend function (such as SUSPENDED state) so we rename
sbi_hsm_hart_started_mask() to something more generic such as
sbi_hsm_hart_interruptible_mask().

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

We replace the use of SBI_STATE_xyz defines with SBI_HSM_STATE_xyz
defines because the HSM state defines are complete enough to implement
HSM state machine in OpenSBI. As a result of this, we can now remove
sbi_hsm_hart_state_to_status() function because it is now redundant
and sbi_hsm_hart_get_state() can directly return HSM state or error.

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

We simplify HSM state define names so that these defines can directly
replace SBI_HART_xyz defines used by SBI HSM implementation.

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

Implement rebooting the K210 via the system reset extension.

All reset types are treated in the same way.
A request for shutdown results in a reboot.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

This patch updates OpenSBI version to 0.9 as part of
release preparation.

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

This clint driver init functions were incorrectly used in
template platform which resulted in compile error. This patch
fixes clint driver function usage in template platform.

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

We don't need to pack struct sbi_platform and sbi_platform_operations
because GCC ensures member offsets match member data type irrespective
to the target system (RV32 or RV64). This also allows GCC to generate
more optimized instruction sequence when accessing members of struct
sbi_platform and struct sbi_platform_operations.

Reported-by: Paul Campbell <taniwha@gmail.com>
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

All members in struct sbi_scrach are of machine word size so no need
to pack this structure. This also allows GCC to generate more optimized
instruction sequence when accessing members of struct sbi_scratch.

Reported-by: Paul Campbell <taniwha@gmail.com>
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

All members in struct sbi_trap_regs are of machine word size so
no need to pack this structure. This also allows GCC to generate
more optimized instruction sequence when accessing members of
struct sbi_trap_regs.

Reported-by: Paul Campbell <taniwha@gmail.com>
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

Currently, the root domain memory regions are fixed in generic
code but some of the platforms may want to explicitly define
memory regions for the root domain.

This patch adds optional domains_root_regions() platform callback
which platforms can use to provide platform specific root domain
memory regions. Due to this changes, the root domain should also
undergo all sanity checks (just like regular domain) so we use
sbi_domain_register() to register root domain.

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

Fix uart_putc implementation.
Due to a bug in the IP, this went unnoticed.
Use macros instead of magic numbers to make the code
more readable.

Signed-off-by: Vijai Kumar K <vijai@behindbytes.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

Currently, we have fixed TLB flush types supported by the
remote TLB library. This approach is not flexible and does
not allow custom local TLB flush function. For example,
after updating PMP entries on a set of HARTs at runtime,
we have to flush TLB on these HARTs as well.

To support custom local TLB flush function, we replace the
"type" field of "struct sbi_tlb_info" with a local TLB flush
function pointer. We also provide definitions of standard TLB
flush operations (such as fence_i, sfence.vma, hfence.vvma,
hfence.gvma, etc).

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

We introduce sbi_trap_exit() API which can help non-firmware
(i.e. generic or platform) code to force exit trap/interrupt
handling and resume execution at context pointed by parameter
"const struct sbi_trap_regs *regs".

This new sbi_trap_exit() API will help Keystone Enclave project
to resume execution of enclave from custom SBI call handler.

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

We had added args pointer in ecall handler to ensure that ecall
handler only implements functionality and does not deal with
SBI calling convention. This also helped us to keep SBI calling
convention related code in one place at sbi_ecall_handler().

The Keystone Enclavce project needs access to the trap regsiters
in their ecall handler so that they can context switch enclaves
in custom SBI calls. To help the Keystone Enclave project, we
replace the args pointer in ecall handler parameter with a const
pointer to trap registers.

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

The misaligned load emulation does not sign-extend values correctly
due to missing sign typecast in value passed to the SET_RD() macro.

A very easy way to reproduce this issue is to load 16-bit value
0xff1e from a byte aligned address using LH instruction on hardware
lacking misaligned load/store.

This patch fixes sbi_misaligned_load_handler() for above issue.

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

The domain_get() platform callback function is now redundant
because fdt_domain_populate() register new domain explicitly
using the sbi_domain_register() function.

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

The fdt_domain_get() function is now redundant because the
fdt_domains_populate() function can explicitly register new
domains using the sbi_domain_register() function.

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

We add sbi_domain_register() function to help platform code register
a new domain explicitly instead of depending on domain_get() platform
callback. This function will eventually help us completely remove the
domain_get() platform callback.

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

We extend fdt_iterate_each_domain() and fdt_iterate_each_memregion()
functions to allow underlying iteration function to fail. This will
help us catch more domain misconfiguration issues at boot time.

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

Sync with libfdt v1.6.0 release source codes.

Signed-off-by: Dimitri John Ledkov <xnox@ubuntu.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

The generic platform should populate domains from FDT using the
domain FDT helper routines.

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

We add various helper routines to populate domains, iterate domains,
iterate domain memregions, and parse HART to domain assignment from
the FDT.

These helper routines can be used by platform support code and FDT
fixup code.

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

This patch adds domain device tree binding documentation in the
OpenSBI domain support documentation.

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

We introduce domains_init() platform operation which can be used by
platform support to initialize/populate domains in the coldboot path.

The domains_init() is called late in the coldboot sequence from the
sbi_domain_finalize() so sbi_printf() can be used by platform support
to print errors/warnings at time of populating domains.

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

We add error prints in sbi_domain_finalize() and sanitize_domain()
to help debug domain configuration issues.

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

If coldboot HART is assigned to a domain then we should use coldboot
HART as the boot HART of the domain. This allows coldboot HART to
continue boot sequence even when it is assigned to some non-root domain.

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

We should use lower bits for domain memory region access permissions
and higher bits for other domain memory region attributes. This helps
us use same bit assignment for parsing domain memory region access
permissions from device tree.

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

The sbi_domain_finalize() should auto start a domain only if the
boot HART is withing limits (i.e. less than SBI_HARTMASK_MAX_BITS).

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

The domain_count check in sbi_domain_finalize() for newly discovered
domain is incorrect and should be reversed.

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