Commit Graph

16 Commits

Author SHA1 Message Date
Bin Meng
650c0e525c lib: sbi: Fix coding style issues
This fixes various coding style issues found in the SBI codes.
No functional changes.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
2020-03-10 10:27:28 +05:30
Anup Patel
00d332bbe7 include: Move bits related defines and macros to sbi_bitops.h
The right location for all bits related defines and macros is
sbi_bitops.h hence this patch. With this patch, the sbi_bits.h
is redundant so we remove it.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-03-08 11:06:18 +05:30
Atish Patra
6704216732 lib: Check MSIP bit after returning from WFI
As per the RISC-V privilege specification, WFI can be implemented as
a NOP. Software should ensure that relevant interrupt pending bits
are set. Otherwise, loop back to WFI.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
2020-03-07 13:15:56 +05:30
Atish Patra
b677a9b8d6 lib: Implement hart hotplug
This patch adds support for hart hotplug in OpenSBI using a generic WFI
based approach. Hart hotplug can be achieved via SBI HSM extension which
allows supervisor mode software to start or stop any harts anytime.

Any platform wishes to implement platform specific hart hotplug must
implement both hart_start and hart_stop in addition to enable platform
feature SBI_PLATFORM_HAS_HART_HOTPLUG.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
2020-02-24 18:07:55 +05:30
Anup Patel
24c3082ea4 lib: Print interrupt and exception delegation in boot prints
We print MIDELEG and MEDELEG CSRs as part of boot prints so that
boot log shows the interrupts and exceptions delegated to S-mode.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-02-19 09:58:48 +05:30
Anup Patel
bc874e34ce lib: Don't check MIDELEG and MEDELEG at end of delegate_traps()
The MIDELEG and MEDELEG CSR checks at end of delegate_traps() were
added for initial bring-up on SiFive Unleashed and QEMU. These
checks are not required any more and in-future these checks can
cause failures because some of the MIDELEG/MEDELEG bits will be
hard-wired to 0 or 1.

For related discussion, refer github issue:
https://github.com/riscv/opensbi/issues/157

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-02-19 09:58:45 +05:30
Anup Patel
2aa43a13cd lib: save/restore MIE CSR in sbi_hart_wait_for_coldboot()
Currently, sbi_hart_wait_for_coldboot() leaves MIE.MSIP bit
set when it returns which is not correct because MIE.MSIP
should be left enabled only by sbi_ipi_init().

This patch does save/restore of MIE CSR to ensure that MIE
CSR is in original state after sbi_hart_wait_for_coldboot()
returns.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-01-07 12:11:25 +05:30
Anup Patel
2be424bd28 lib: Extend trap redirection for hypervisor v0.5 spec
The hypervisor v0.5 spec introduces two new CSRs for both M-mode
and HS-mode which need to be considered when redirecting traps
hence this patch.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
2019-12-16 14:48:26 +05:30
Anup Patel
6590a7dab9 lib: Delegate guest page faults to HS-mode
As-per RISC-V hypervisor v0.5 spec, we have new guest page faults
which need to be delegated to HS-mode.

Also, we can have bits in in MIDELEG and MEDELEG hardwired to 1
which means we need to fix the sainty check on these CSRs at the
end of delegate_traps() function.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
2019-12-16 14:48:16 +05:30
Anup Patel
e561c63036 lib: Fix coldboot race condition observed on emulators/simulators
If we are running on RISC-V emulator/simulator with large number of
HARTs where each HART is a regular thread under UNIX host then it is
possible that some of the secondary HARTs don't get chance to run and
sbi_hart_wake_coldboot_harts() is called before secondary HARTs call
sbi_hart_wait_for_coldboot(). In this situation, some of the secondary
HARTs will never come-out of coldboot wait loop.

To tackle this, we introduce a global flag coldboot_done which will
be protected by coldboot lock and it will be set by primary HART from
sbi_hart_wake_coldboot_harts() before waking-up secondary HARTs. We
also re-arrange acquire/release of coldboot lock to reduce further
chances of race-condition.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Zong Li <zong.li@sifive.com>
Reviewed-by: Nylon Chen<nylon7@andestech.com>
2019-10-02 17:03:58 +05:30
Anup Patel
1a5614e971 lib: Extend sbi_hart_switch_mode() to support hypervisor extension
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>
2019-09-30 15:18:06 +05:30
Anup Patel
0089897d41 lib: Delegate supervisor ecall to HS-mode when H extension available
When hypervisor extension is available, we only handle hypervisor
ecalls coming from HS-mode and we let hypervisor handle ecalls coming
from VS-mode.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
2019-09-30 15:14:00 +05:30
Zong Li
1ed9eb255d Write MSIP by using memory-mapped control register
The machine-level MSIP bits are written by accesses to memory-mapped
control registers. Only use CSR instruction for SSIP and USIP.

There is no effect that using CSR instruction to write MSIP when testing
on unleashed board and QEMU.

Signed-off-by: Zong Li <zong.li@sifive.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
2019-09-28 18:23:13 +05:30
Jacob Garber
3f738f5897 lib: Use bitwise & instead of boolean &&
!(mipval && MIP_MSIP) simplifies to !mipval, which checks if the entire
variable is zero, not just a single bit. Fix this to use bitwise &
instead.

Signed-off-by: Jacob Garber <jgarber1@ualberta.ca>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2019-08-12 09:22:20 +05:30
Anup Patel
0f18b3fe0a lib: Allow compiling without FP support
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>
2019-07-26 15:49:49 +05:30
Atish Patra
749b0b0932 lib: Move sbi core library to lib/sbi
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Acked-by: Anup Patel <anup.patel@wdc.com>
2019-06-19 09:48:51 +05:30