Commit Graph

40 Commits

Author SHA1 Message Date
Anup Patel a38bea9341 lib: sbi_hart: Detect number of supported PMP regions
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>
2020-05-19 09:19:48 +05:30
Anup Patel 63b0f5f71a include: sbi: Use scratch pointer as parmeter in HART feature APIs
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>
2020-05-19 09:19:42 +05:30
Anup Patel 3a8fc81357 lib: sbi: Print platform HART count just before boot HART id
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>
2020-05-19 09:19:39 +05:30
Anup Patel 3aa1036f91 lib: sbi: Remove extra spaces from boot time prints
We remove extra spaces from boot time prints.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-05-19 09:19:37 +05:30
Anup Patel 49841832b8 lib: sbi: Improve get_feature_str() implementation and usage
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>
2020-05-19 09:19:34 +05:30
Atish Patra 22c4334f5c lib: Add hart features in boot time print
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>
2020-05-10 10:30:47 +05:30
Atish Patra 1f235ec47f lib: Add platform features in boot time print
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>
2020-05-10 10:24:08 +05:30
Anup Patel dc38929dfb lib: sbi: Improve misa_string() implementation
The RISC-V ISA string does not follow alphabetical order. Instead,
we have a RISC-V specific ordering of extensions in the RISC-V ISA
string. This patch improves misa_string() implementation to return
a valid RISC-V ISA string.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-05-07 09:08:26 +05:30
Anup Patel 1f21b99ff0 lib: sbi: Print platform hart count at boot time
Now that we have generic platform which detects hart count from
DTB, we should print platform hart count at boot time.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-05-01 10:33:08 +05:30
Anup Patel ec0d80f5b4 include: sbi_system: Remove scratch parameter and redundant functions
This patch removes scratch parameter and redundant functions from
sbi_system.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-03-28 13:32:52 +05:30
Anup Patel dd0f21c560 lib: sbi_scratch: Introduce sbi_scratch_last_hartid() API
The patch adds sbi_scratch_last_hartid() API which returns
last HART id having a scratch space. We can use this new API
to optimize places where we iterate over HART id from 0 to
SBI_HARTMASK_MAX_BITS.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-03-28 13:32:41 +05:30
Anup Patel 5b6957eed7 include: Use more consistent name for atomic xchg() and cmpxchg()
We should remove the "arch_" prefix from atomic xchg() and cmpxchg()
function names to have consistent naming of all atomic functions.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-03-28 13:32:38 +05:30
Xiang Wang 4d93586bfa lib: prevent coldboot_lottery from overflowing
HSM_STOP will trigger multiple executions of sbi_init, atomic_add_return may
trigger coldboot_lottery overflow

Signed-off-by: Xiang Wang <merle@hardenedlinux.org>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
2020-03-26 17:32:34 +05:30
Atish Patra 9a74a64ae0 lib: Check MSIP bit after returning from WFI
Commit 71d2b837c4 (lib: Move all coldboot wait APIs to sbi_init.c)
caused a regression while moving the code from sbi_hart.c to sbi_init.c.

As per original commit text, WFI can be implemented as a NOP according
to the RISC-V privilege specification. Software should ensure that
relevant interrupt pending bits are set. Otherwise, loop back to WFI.
Fix the regression by applying the original patch to sbi_init.c.

Fixes: 71d2b837c4 ("lib: Move all coldboot wait APIs to sbi_init.c")

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
2020-03-21 09:21:47 +05:30
Anup Patel c51f02cf14 include: sbi_platform: Introduce HART index to HART id table
A platform can have discontinuous and/or sparse HART ids so we
cannot always assume a set of HARTs with continuous HART ids.

This patch adds support for discontinuous and sparse HART ids by
introducing HART index to HART id table. This table has platform
hart_count entries and it maps HART index to HART id.

The HART index to HART id table has only two restrictions:
1. HART index < sbi_platform hart_count
2. HART id < SBI_HARTMASK_MAX_BITS

Example1:
Let's say we have a platform with 2 HART ids 11 and 22, for such a
a platform:
hart_count = 2
hart_index2id[0] = 11
hart_index2id[1] = 22

Example2:
Let's say we have a platform with 5 HARTs ids 0, 1, 2, 3, and 4
but out of these HART with id 0 is not usable so for such a platform:
hart_count = 5
hart_index2id[0] = -1U
hart_index2id[1] = 1
hart_index2id[2] = 2
hart_index2id[3] = 3
hart_index2id[4] = 4
OR
hart_count = 4
hart_index2id[0] = 1
hart_index2id[1] = 2
hart_index2id[2] = 3
hart_index2id[3] = 4

With HART index to HART id table in place, the hart_disabled()
callback is now redundant so we remove it as well.

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>
2020-03-19 09:30:01 +05:30
Anup Patel 75eec9dd3f lib: Don't use sbi_platform_hart_count() API
We don't need to use sbi_platform_hart_count() in sbi_init and
sbi_scratch because checking sbi_platform_hart_disabled() or
return value of sbi_hartid_to_scratch() is sufficient.

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>
2020-03-19 09:27:51 +05:30
Anup Patel 209134d8f9 lib: Handle failure of sbi_hartid_to_scratch() API
The sbi_hartid_to_scratch() API can fail for non-existent HARTs so
all uses of sbi_hartid_to_scratch() API should check return value.

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>
2020-03-19 09:11:12 +05:30
Anup Patel e23d3ba936 include: Simplify HART id to scratch macro
This patch simplify HART id to scratch macro as follows:
1. Remove current "scratch" pointer argument because now we
   use HART id to scratch table
2. Rename sbi_hart_id_to_scratch() to sbi_hartid_to_scratch()
   to have macro name consistent with the name of callback
   in struct sbi_scratch

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>
2020-03-19 09:04:29 +05:30
Anup Patel 87a7ef7659 lib: sbi_scratch: Introduce HART id to scratch table
Instead of calling hartid_to_scratch() callback every time when
we want sbi_scratch pointer from HART id, we create a table of
sbi_scratch pointers and use that to get sbi_scratch pointer.

As a result of HART id to scratch table, the conversion of
HART id to sbi_scratch pointer is just 2-3 instructions which
was 9 instructions previously.

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>
2020-03-19 09:02:23 +05:30
Anup Patel 823345ecae include: Make sbi_current_hartid() as macro in riscv_asm.h
The sbi_current_hartid() being a regular function is quite
expensive because for callers it is a function call instead
of a direct CSR read. This patch converts sbi_current_hartid()
into a macro in riscv_asm.h.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-03-13 12:22:02 +05:30
Anup Patel eede1aa7c7 lib: sbi_hart: Remove HART available mask and related APIs
The HART available mask and related APIs are now totally redundant
because of more extensive HART state machine implemented by sbi_hsm.

Due to above, we remove HART available mask and related APIs.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
2020-03-11 15:30:30 +05:30
Anup Patel 2b945fc180 lib: sbi_init: Use hartmask for coldboot wait
The coldboot_wait_bitmap is of fixed size and has __riscv_xlen
bits. This limits us to scale beyond __riscv_xlen HARTs hence
we replace coldboot_wait_bitmap with coldboot_wait_hmask which
is of type struct sbi_hartmask.

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>
2020-03-11 15:30:08 +05:30
Anup Patel 71d2b837c4 lib: Move all coldboot wait APIs to sbi_init.c
The coldboot wait APIs are only used by sbi_init.c so no point in
having coldboot related code in sbi_hart.c.

As per-above rationale, we move all coldboot wait related APIs to
sbi_init.c as static/local functions.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
2020-03-11 15:30:00 +05:30
Anup Patel d6d7e18d1d lib: sbi_init: Don't allow HARTID greater than SBI_HARTMASK_MAX_BITS
We only allow HARTs with HARTID less than SBI_HARTMASK_MAX_BITS in
sbi_init() function so that sbi_hartmask can safely used across
OpenSBI sources.

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>
2020-03-11 15:29:51 +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 37923c4a66 lib: Add dynamic registration of SBI extensions
This patch extends our SBI ecall implementation to allow
dynamic registration of various SBI extensions. Using this
dynamic registration we can break-up SBI ecall implementation
into multiple files and even register experimental/custom
SBI extensions from platform code.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-01-22 12:13:34 +05:30
Anup Patel 84cd4fc913 lib: Initialize TLB management directly from coldboot/warmboot path
Currently, the remote TLB management is initialized via IPI init
which is counter intuitive. This patch initializes remote TLB
management directly from init_coldboot() and init_warmboot()
after IPI init is done.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-01-22 12:10:49 +05:30
Anup Patel a67fd68cbf lib: Add sbi_init_count() API
We add sbi_init_count() API which provides number of times a
given HART completed init sequence (warmboot/coldboot).

This will be very useful in debugging. With upcoming SBI HSM
extension, it will also help in implementing one-time init
code for each HART.

Signed-off-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-01-07 12:11:48 +05:30
Anup Patel 1993182f03 lib: Add irqchip exit API
We add an optional platform irqchip exit hook for exit path handling
in sbi_exit() implementation.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-01-07 12:11:19 +05:30
Anup Patel b325f6baef lib: Add ipi exit API
We add sbi_ipi_exit() API for exit path handling in sbi_exit()
implementation.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-01-07 12:11:02 +05:30
Anup Patel 6469ed101c lib: Add timer exit API
We add sbi_timer_exit() API for OpenSBI exit path handling in
sbi_exit() implementation.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-01-07 12:10:55 +05:30
Anup Patel 55e191e3b0 lib: Add system early_exit and final_exit APIs
This patch adds system-level early_exit and final_exit APIs
with corresponding platform hooks. These new APIs will be
primarily used by sbi_exit() in OpenSBI exit path.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-01-07 12:10:48 +05:30
Anup Patel c3e406f160 lib: Add initial sbi_exit() API
This patch adds initial implementation of sbi_exit() API which
can be used to perform OpenSBI exit sequence for current HART.

The sbi_exit() implementation will be further extended by
subsequent patches.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-01-07 12:10:35 +05:30
Anup Patel e746673a79 lib: Remove unnecessary checks from init_coldboot() and init_warmboot()
We remove unnecessary checks related to hart hotplug and disabled
hart in coldboot and warmboot init path.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-01-07 10:22:24 +05:30
Xiang Wang c96cc03fcc lib: Fix CPU capabilities detection function
On some platforms, misa may not be implemented. On such a platform,
reading misa will get 0. At this time, platform is required to
implement a non-standard function to detect the CPU's capabilities.
Therefore, this modification add interfaces for non-standard function.

The MXL field of misa is always at the highest two bits, whether it
is a 32-bit 64-bit or a 128-bit machine. Therefore, this modification
fixes the use of a fixed offset to detect the machine length.

Signed-off-by: Xiang Wang <merle@hardenedlinux.org>
Signed-off-by: Anup Patel <anup.patel@wdc.com>
2019-11-26 16:06:29 +05:30
Alistair Francis 215421ca61 lib: Remove date and time from init message
Building the date and time into the binary means the OpenSBI isn't
reproducible. We don't really need the time so let's remove it.

Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
2019-11-15 17:42:55 +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
Palmer Dabbelt a2a7763ac7 Include `git describe` in OpenSBI
OpenSBI includes a version, but that is only updated when tagged.  For
users that are using the git releases we instead end up with an
ambiguous version number, which makes it hard to figure out what
everyone is using.  This patch checks for a git directory and prints out
the result of `git describe`, which is a mix of pretty and unambiguous.

Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
2019-08-19 10:58:21 +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