SBI v0.2 introduces a base specification which is mandatory to
implement for any SBI implementations that is not legacy.
Add support for the base extension.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
Current SBI implementation is now considered as version 0.1 and will be
removed/replaced with newer extension/functions in future.
Rename the existing implementations accordingly to be in sync with the
specification.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Zong Li <zong.li@sifive.com>
Test payload uses an SBI call and uses the macros defined in interface
header which is not the correct place to have these definitions.
The interface header file should be used to keep SBI specification
related macros.
Keep all the test payload related code in test itself.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
For platforms not having TIME CSR, we trap-n-emulate TIME CSR
read/write in OpenSBI. Same rationale applies to HTIMEDELTA CSR
as well so we trap-n-emulate HTIMEDELTA CSR for platforms not
having TIME CSR.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Current implementation of get_insn() is not suitable for reading
instruction from VS/VU mode because we have to set SSTATUS_MXR bit
in VSSTATUS CSR for reading instruction from VS/VU mode.
This patch extends get_insn() to read instruction from VS/VU mode.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
The WFI will trap as illegal instruction trap when executed
in VS/VU mode so we just forward/redirect it to HS-mode so
that hypervisor can deal with it appropriately.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
When hypervisor extension is available, we can get traps from VS/VU
modes. We should be able to force redirect some of these traps to
HS-mode. In other words, we should be able forward traps from VS/VU
mode to HS-mode using sbi_trap_redirect() hence this patch.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
This patch extends sbi_hart_switch_mode() to support entering
VS/VU modes when hypervisor extension is available.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Use platform defined flush range limit value only if it is non-zero.
Otherwise, use the default value.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Currently, the tlb range flush threshold is fixed and set to 4k for
all platforms. However, it should be platform specific as it completely
depends upon how platform actually implements sfence instruction.
Define a platform feature that allows every individual platform to set
different values. If a platform doesn't define it, just use a page size as
the threshold.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
In RISC-V, tlb flush happens at a page granularity. That's why OpenSBI
also have a tlb range flush limit which decides the which tlb flush
requests should be upgraded to full flush to avoid long delays.
Currently, this is set to 1G which would result in a many sfence.vma
execution in a tight loop for a large range.
Change the threshold to 4k to speed things up.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
OpenSBI manages outstanding TLB flush requests by queueing
them in a fifo synchronously. An ipi sync which uses an
atomic operation on MMIO address is no longer required.
Remove the ipi sync method from platform header and all usage.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
Linux kernel expects tlb flush SBI call to be completely synchronous i.e.
the SBI call should only return once corresponding *fence* instruction is
executed.
OpenSBI manages the outstanding TLB flush requests by keeping them in a
per hart based fifo. However, there are few corner cases that may lead to
race conditions while updating the fifo.
Currently, the caller hart waits for IPI acknowledgement via clint
address which is not a very good method as synchronization on MMIO may not
be supported in every platform. Moreover, the waiter doesn't have any way of
identifying if the IPI is received for specific tlb flush request or any
other IPI. This may lead to unpredictable behavior in supervisor/user space.
Fix this by waiting on individual fifo entries rather than MMIO address.
Currently, a relaxed loop is being used because wfi again involves MMIO write
which would be slower compared to relaxed loop. To avoid deadlock, fifo
is processed every time a hart loops for fifo enqueue or fifo sync to consume
the tlb flush requests sent by other harts.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Signed-off-by: Atish Patra <atish.patra@wdc.com>
We can get a page/access trap when doing unpriv load/store in
get_insn() function because on a SMP system Linux swapper running
on HART A can unmap pages from page table used by HART B.
To tackle this we extend get_insn() implementation so that if
we get trap in get_insn() then we redirect it to S-mode as fetch
page/access fault.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
This patch introduces new sbi_dprintf() API for runtime debug
prints. The sbi_dprintf() will print to console for a given
HART only when SBI_SCRATCH_DEBUG_PRINTS option in enabled in
sbi_scratch for this HART.
We can now add debug prints using sbi_dprintf() at important
places in OpenSBI sources. These debug prints will only show
up when previous booting stage or compile time parameter sets
the SBI_SCRATCH_DEBUG_PRINTS option in scratch space.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Currently, we mandate 'F' and 'D' extension in riscv_fp.h so that
misaligned load/store emulation has access to FP registers.
The above is too restrictive and we should certainly allow compilation
for soft-FP toolchains and explicit PLATFORM_RISCV_ISA not having 'F'
and 'D' extensions.
This patch extends riscv_fp.h and misaligned load/store emulation to
allow compiling OpenSBI without FP support.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
There are several places in the source tree that have:
32bit, 32 bit, 64bit, 64 bit
Fix by using the conventional names with a hyphen.
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Acked-by: Anup Patel <anup.patel@wdc.com>
Add version control of sbi_platform structure
- Add opensbi_version, this gives information of opensbi revision on
which the sbi_platform table was created.
- Add platform_version field in sbi_platform structure for platform
level version control.
Signed-off-by: Abner Chang <abner.chang@hpe.com>
Acked-by: Anup Patel <anup.patel@wdc.com>
Move platform opensbi functions to sbi_platform_operations structure.
Both sbi_platform and sbi_platform_operations structures are maintained
by platform vendors.
Signed-off-by: Abner Chang <abner.chang@hpe.com>
Acked-by: Anup Patel <anup.patel@wdc.com>
tinyfdt.c was originally added to provide a minimal implementation of
fdt parsing. However, we have already included libfdt in OpenSBI for
more complicated operations.
Remove tinfdt and replace its functiolity using libfdt.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Acked-by: Anup Patel <anup.patel@wdc.com>
All string functions are part of libsbi. It makes more sense
to rename them to sbi_string.x as the libsbi can be linked
with external libraries that can have similar implementation.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Acked-by: Anup Patel <anup.patel@wdc.com>
Currently, platform/common contains platform/non-platform specific
common minimal drivers and libraries. This is helpful is all platforms
are built within opensbi framework.
Move them to lib/utils so that any external platform code also can
reuse the minimalistic drivers or other common libraries.
This patch doesn't introduce any functional changes.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Acked-by: Anup Patel <anup.patel@wdc.com>
libsbi needs some of the custom libc functions. It should be directly
included in libsbi instead of platform specific libraries.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Acked-by: Anup Patel <anup.patel@wdc.com>
The unpriv load/store instruction from M-mode can cause page/access
fault to M-mode if S-mode page table did not have mappings OR it did
not have PMP access permission.
To tackle this, we redirect trap back to S-mode if unpriv load/store
instruction traps in M-mode.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
This patch adds per-HART trap info pointer which can be used to
communicate trap information to sbi_trap_handler().
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Currently, the unprivilege load/store functions are inline functions.
We will be extending these functions to track whether a page/access
fault occurs when we execute unprivilege load/store instruction.
To make things simpler and debugable, we reduce number of places which
can potentially generate a page/access fault by making all unprivilege
load/store functions as regular (non-inline) functions.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
This patch factor-out TLB management from IPI management to separate
sources sbi_tlb.c and sbi_tlb.h.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
We have extra space above scratch space (sbi_scratch) which we are
currently using to manage per-HART IPI data and TLB request management.
In future, more parts of OpenSBI will use the extra scratch space so
it will become difficult to manage extra scratch space using just
defines and macros.
This patch adds a simple brain-dead allocator to manage extra scratch
space. This allocator never expects anything to be free-ed hence it
keeps incrementing to next allocation offset until it runs-out of space.
In future, we can have more sophisticated allocator which will allow
us to re-claim free-ed space and also allows us to track owner of
allocated space.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
On latest Linux kernel (i.e. 5.2-rc1), we get large TLB flush
request for user space addresses (typically, start=x and end=-1).
This is caused by Linux kernel commit a21344dfc6 ("riscv: fix
sbi_remote_sfence_vma{,_asid}").
It's not practical to execute large number of sfence instructions
for a large TLB flush range because it takes too much time and
eventually causes CPU stall in Linux kernel.
This patch addresses above issue by upgrading TLB flush range to
TLB flush all whenever TLB flush range is greater than 1GB.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
This patch provides first-cut implementation of fw_dynamic firmware.
As compared to fw_jump and fw_payload, the fw_dynamic obtains next
address, next mode and OpenSBI options from struct fw_dynamic_info.
The previous booting stage can create struct fw_dynamic_info in memory
and pass address of struct fw_dynamic_info in 'a2' register. Also, the
struct fw_dynamic_info has versioning as well so changes to the struct
fw_dynamic_info can be done in a backward compatible manner.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Noisy commit, no functional changes.
Generated with an current upstream clang-format and:
clang-format -i $(find . -name \*.[ch])
Signed-off-by: Olof Johansson <olof@lixom.net>
One of the shortcomings of clang-format is that it doesn't allow
for aligned define tables, which is used for a number of constants.
Add annotation to disable the automatic formatting where needed.
Signed-off-by: Olof Johansson <olof@lixom.net>
Implement a lock enabled iteration for fifo so that
caller can determine if next entry can be skipped or
any existing entries in fifo can be updated before enqueue.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
This patch reduces memory consumed by struct sbi_fifo by droping
redundant "head" member and using u16 in-place of "unsigned long".
Signed-off-by: Anup Patel <anup.patel@wdc.com>
This patch does following improvements to sbi_fifo:
1. Use valid SBI_Exxxx error codes instead of -1
2. The sbi_fifo_is_full() and sbi_fifo_is_empty() did
not acquire qlock before accessing head and tail
hence fixed it
3. Added avail member for ease in debugging and simplifying
head/tail updates.
Due to above changes size of sbi_fifo changes from 48 bytes
to 56 bytes.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Currently, there is no provision for tracking multiple IPIs sent
to a single hart at the same time by different harts.
Use a fifo manage the outstanding requests. While dequeueing, read all
the entries once, because we have only 1 bit to track the type of IPI.
Once the queue is full, busy wait until the there is space available in
queue. This is not the most elegant approach. It should be changed in
favor of a wakeup event once available in opensbi.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
The mstatus parameter of get_insn() is used to return MSTATUS CSR
value which get_insn() saw. Most of the get_insn() callers don't
use the value returned in mstatus so this patch makes mstatus
parameter optional for get_insn().
Signed-off-by: Anup Patel <anup.patel@wdc.com>
The sbi_unpriv.h has quite a few load_xyz() and store_xyz() helper
routines based on RISC-V inline assembly for unpriviledged accesses
from M-mode. These helper routines are similar to helper routines
present in riscv_locks.h, riscv_io.h, and riscv_atomic.h so let's
rename sbi_unpriv.h to riscv_unpriv.h.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Introduce "options" in "struct sbi_scratch" and firmware can update
it based on optional compile time flags before calling sbi_init().
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
