The coldboot HART jumps to the next booting stage at the end of
init_coldboot() so it is absolutely necessary for coldboot HART
to support the privilege mode expected by the next booting stage.
We extend the coldboot HART selection in sbi_init() to ensure that
the selected coldboot HART always supports privilege mode specified
in scratch space (i.e. scratch->next_mode). This will further help
us allow E-core (without MMU) on SiFive Unleashed and PolarFire
ICICLE boards to proceed further and wait in HSM STOPPED state.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
The fdt_cpu_fixup() should work fine even if HARTs without MMU
are not marked invalid by platform support code.
In future, we plan to treat HARTs without MMU as valid in the
generic platform support so that we can hold these HARTs in
HSM STOPPED state.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
We extend sbi_hart_pmp_check_addr() API so that users can specify
privilege mode of the address for checking PMP access permissions.
To achieve this, we end-up converting "unsigned long *size" parameter
to "unsigned long *log2len" for pmp_get() implementation so that we
can deal with regions of "1UL << __riscv_xlen" size in a special case
in sbi_hart_pmp_check_addr() implementation.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
The sbi_scratch already has provision to specify the next stage mode
so we can leverage this to specify start mode to sbi_hsm_hart_start().
In future, this will be useful in providing SBI calls to U-mode on
embedded cores where we M-mode and U-mode but no S-mode.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
We should allow M-mode to M-mode ECALLs because:
1. No other mode can handle M-mode ECALLs
2. In future, we can allow M-mode baremetal application (not
linked to OpenSBI) running independently and cooperatively
without corrupting OpenSBI M-mode state (CSRs and memory).
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
We rename CAUSE_HYPERVISOR_ECALL to CAUSE_SUPERVISOR_ECALL and
CAUSE_SUPERVISOR_ECALL to CAUSE_VIRTUAL_SUPERVISOR_ECALL so that
it matches latest RISC-V privilege spec.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
The VS-mode ecall is supposed to be handled by HS-mode so
sbi_trap_handler() should fallback to default case for
VS-mode ecall trap.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
We improve HPM CSR read/write emulation as follows:
1. Fail for unimplemented counters so that trap is redirected
to S-mode which can further help debugging S-mode software.
2. Check permissions in both MCOUNTEREN and SCOUNTEREN for
HS-mode and U-mode.
3. Don't check permissions for TIME CSR because we emulate
TIME CSR for both Host (HS/U-mode) and Guest (VS/VU-mode).
Also, faster TIME CSR read is very helpful for good
performance of S-mode software.
4. Don't emulate S-mode CSR read/write to M-mode HPM CSRs
because these should not be accessible to S-mode software.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
A RISC-V platform can leave unimplemented MHPM counters hard-wired
to zero. We extend hart_detect_features() to detect MHPM counters
which are accessible and not hard-wired to zero. We also print
number of available MHPM counters as part of boot prints.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
As-per latest RISC-V privilege spec up to 64 PMP entries are supported.
Implementations may implement zero, 16, or 64 PMP CSRs. All PMP CSR
fields are WARL and may be hardwired to zero.
This patch improves PMP CSR detection and progamming considering
above facts.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
The SBI_HART_HAS_PMP feature is redundant because we already
have number of PMP regions returned by sbi_hart_pmp_count().
Checking whether PMP is supported for a HART can be simply done
by checking non-zero value returned by sbi_hart_pmp_count().
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 Kendryte K210 follows RISC-V v1.9 spec so MTVAL has instruction
address (instead of instruction encoding) on illegal instruction trap.
To handle above case, we fix sbi_illegal_insn_handler() without any
impact on RISC-V v1.10 (or higher) systems. This achieved by exploiting
the fact that program counter (and instruction address) is always 2-byte
aligned in RISC-V world.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Tested-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: Bin Meng <bin.meng@windriver.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
We can have thundering hurd problem with coldboot_lock where the
boot HART can potentially starve trying to acquire coldboot_lock
because some of the non-boot HARTs are continuously acquiring and
releasing coldboot_lock. This can happen if MIP.MSIP bit is already
set for some of the non-boot HARTs.
To avoid thundering hurd problem for coldboot_lock, we use the
__smp_load_acquire() and __smp_store_release() for coldboot_done
flag and use coldboot_lock only for coldboot_wait_hmask.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Tested-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Bin Meng <bin.meng@windriver.com>
When redirecting from VS/VU-mode to HS-mode, hstatus.SPVP was set
to the value of mstatus.SPP, as according to the specification both
flags should be set to the same value.
However, the assignment of SPVP takes place before SPP itself is
updated, which results in SPVP having an outdated value.
Signed-off-by: Georg Kotheimer <georg.kotheimer@tu-dresden.de>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
If MTINST[0:0] bit is 1 then we have transformed instruction encoding
in MTINST CSR. For transformed instructions, if the MTINST[1:1] bit
is Zero then original trapped instruction was a 16bit instruction
which was converted to 32bit instruction at time of taking trap.
We should use MTINST[1:1] bit to determine correct instruction length
of transformed instruction.
This patch updates misaligned load/store emulation as-per above.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Use strncmp instead of using sbi_strcmp directly in fdt_parse_hart_id()
to allow compiling fdt_helper.c by external firmware.
Signed-off-by: Abner Chang <abner.chang@hpe.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
Currently 256 bytes is used for the FDT expand size when fixing up
reserved memory node. Increase it to 1024 bytes with an estimated
size of 64 bytes per PMP memory region by 16 regions in total.
Signed-off-by: Bin Meng <bin.meng@windriver.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
We should only return valid error codes from SBI ecalls as
defined by the RISC-V SBI spec.
To achieve this:
1. We use SBI_Exxxx defines for OpenSBI internal errors with
error values starting from -1000
2. We use SBI_ERR_xxxx defines for errors defined by SBI spec
3. We map some of the SBI_Exxxx defines to SBI_ERR_xxxx defines
which are semantically same
4. We throw a error print and force return error code to
SBI_ERR_FAILED in sbi_ecall_handler() if we see an invalid
error code being returned to S-mode
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
On RV64,"unsigned long" is 64bit and "unsigned int" is 32bit. So in
function "pmp_get" and "pmp_set", if "pmpcfg_shift >= 32", "0xff << pmpcfg_shift"
will go beyond "unsigned int" width. This patch tries to fix this issue.
In function 'pmp_get':
cfgmask = (0xff << pmpcfg_shift);
-->
cfgmask = (0xffUL << pmpcfg_shift);
In function 'pmp_set':
cfgmask = ~(0xff << pmpcfg_shift);
-->
cfgmask = ~(0xffUL << pmpcfg_shift);
Signed-off-by: Liush <liush.damon@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
C-Class is a member of the SHAKTI family of processors from Indian
Institute of Technology - Madras(IIT-M).
It is an extremely configurable and commercial-grade 5-stage in-order
core supporting the standard RV64GCSUN ISA extensions.
https://gitlab.com/shaktiproject/cores/c-class/blob/master/README.md
We add OpenSBI support for Shakti C-class SoC.
Signed-off-by: Vijai Kumar K <vijai@behindbytes.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
This is achieved by removing the 'no-map' property from the
'reserved-memory' node when PMP is present, otherwise we keep it as it
offers a small protection if the OS does not map this region at all.
A new callback in platform_override is introduced and allows to fixup the
device-tree. It is used here to override this new default behaviour on
SiFive Fu540 platforms that has an erratum that prevents S-mode software
to access a PMP protected region using 1GB page table mapping.
If PMP is present, telling the OS not to map the reserved regions does not
add much protection since it only avoids access to regions that are already
protected by PMP. But by not allowing the OS to map those regions, it
creates holes in the OS system memory map and prevents the use of
hugepages which would generate, among other benefits, less TLB miss.
Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
The arguments/parameters of __sbi_hfence_gvma_vmid_gpa() and
__sbi_hfence_vvma_asid_va() functions are swapped so we fix it.
Currently, we did not face any issues because QEMU does a full
TLB flush for all HFENCE instructions.
We also improve documentation of HFENCE.GVMA and HFENCE.VVMA
instruction encoding.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
To support RISC-V hypervisor v0.6.1, we:
1. Don't need to explicitly forward WFI traps from VS/VU-mode
2. Have to delegate virtual instruction trap to HS-mode
3. Have to update trap redirection for changes in HSTATUS CSR
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
We can have multiple matching DT nodes of the same FDT timer driver
so in this case we should call cold_init() for all matching DT nodes
instead of just first matching DT node.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
We can have multiple matching DT nodes of the same FDT ipi driver
so in this case we should call cold_init() for all matching DT nodes
instead of just first matching DT node.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
We add fdt_parse_clint_node() function which will be used by
fdt_ipi_clint and fdt_timer_clint drivers to parse CLINT details
from DT node.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
We extend CLINT cold init function to have a "struct clint_data *"
parameter pointing to CLINT details. This allows platforms to use
CLINT functions for multiple CLINT instances.
When multiple CLINTs are present, the platform can also provide
one of the CLINT as reference CLINT for other CLINTs. This will
help CLINTs to sync their time value with reference CLINT using
a time_delta computed in warm init function.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
We can have multiple matching DT nodes of the same FDT irqchip
driver so in this case we should call cold_init() for all matching
DT nodes instead of just first matching DT node.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
We extend fdt_find_match() implementation by adding node offset
parameter which represents the first node to match from.
The improved fdt_find_match() can be used to find multiple
match nodes.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
We extend all PLIC functions to have a "struct plic_data *"
parameter pointing to PLIC details. This allows platforms to
use these functions for multiple PLIC instances.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
The "target_hart" and "hart_count" parameters of PLIC cold and
warm init functions are only used for sanity checks and not
required in PLIC initialization.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
It is not mandatory for a RISC-V systems to implement all PMP
regions so we have to check all PMPADDRx CSRs to determine excat
number of supported PMP regions.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
This patch does few cosmetic improvements to HART feature detection:
1. Remove sbi_ perfix from HART feature detection functions
because all local/static functions in sbi_hart.c don't have
sbi_ prefix
2. Remove sbi_hart_set_feature() because it's quite small and
local/static in sbi_hart.c
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
It makes more sense to have scratch pointer as parameter in
HART feature APIs because:
1. We already have scratch pointer at places where these APIs
are used.
2. This is consistent with lot of other APIs in sbi_hart.h
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
On platforms with continuous HART ids starting from zero:
0 <= boot HART id < platform HART count
The above co-relation of boot HART id and platform HART count
is true for most RISC-V platfors so it's better to print platform
HART count just before boot HART id.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
We do following improvements for get_feature_str():
1. We should return "none" from get_feature_str() no features
available instead of sbi_boot_prints() explicitly handling
failure.
2. We don't need to return failure (just like misa_xlen())
because we are returning "none" for no features and we are
truncating output when space is not available.
3. Based on 1 and 2, the sbi_boot_prints() can be further
simplified.
4. No need for two char[] in sbi_boot_prints()
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
We should detect HART features in sbi_hart_init() before
mstatus_init(), delegate_traps() and pmp_init().
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Currently, unprivileged access functions uses few additional instructions
which are redundant. It also uses specific registers which are not necessary.
Remove those additional instructions and let the compiler choose the
registers.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
We have now clear distinction between platform and hart features.
Modify the boot print messages to print hart specific features in
a string format.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Tested-by: Jonathan Balkind <jbalkind@cs.princeton.edu>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
We have now clear distinction between platform and hart features.
Modify the boot print messages to print platform features in a string
format. In the process, this patch moved relatively larger functions
to its own file from platform.h header file.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Tested-by: Jonathan Balkind <jbalkind@cs.princeton.edu>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
As per the RISC-V specification, time value can be obtained from a time
CSR implemented in hardware or a MMIO based IP block. Qemu virt machine
already supports timer csr while CLINT provides the timer for other
platforms.
Implement a hart specific timer feature that can be detected at runtime.
As CSR based timer implementation are faster than MMIO address based, it
is always preferred over MMIO based one.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Tested-by: Jonathan Balkind <jbalkind@cs.princeton.edu>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
PMP & performance counters belong to a hart rather than a platform.
In addition to that, these features enable reading/writing from a
particular csr. Thus, they can be detected and set at runtime rather
than compile time.
Move PMP/MCOUNTEREN/SCOUNTEREN features to hart and detect them at runtime.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Tested-by: Jonathan Balkind <jbalkind@cs.princeton.edu>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
There may be some features which are hart specific rather than a platform
specific feature. Add a framework to support that.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Tested-by: Jonathan Balkind <jbalkind@cs.princeton.edu>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
As per RISC-V ISA, pmp is not mandatory. Currently, we only add reserved
memory node in DT only if PMP is present. That allows supervisor to access
the memory where OpenSBI continue to exist without realizing it for non-pmp
based platforms. It may result in corrupting OpenSBI. That's why OpenSBI
should at least let the supervisor know where it continue to exist.
This a best effort service provided by OpenSBI expecting that supervisor
software is not buggy and properly sets up its memory after parsing the
reserved-memory device tree node.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
There may be few common mathematics helper functions which can be used
anywhere in OpenSBI project.
Add a separate math helper function file to add these functions.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
