fw_base: Put data in .data rather than .text

The -N linker option is supposed to make .text writable, but GNU ld and
LLD differ in interpreting what that means. GNU ld will happily let you
have relocations in it, but LLD will see that the input section is
read-only (even though the output section is writable) and give an
error. It's unclear if either of them intend to have that behaviour in
this edge case, but regardless there's no reason not to just put the
data in a writable .data section.

Signed-off-by: Jessica Clarke <jrtc27@jrtc27.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

fw_base: Don't mark fw_platform_init as both global and weak

These are mutually exclusive. GNU as and LLVM both let later binding
directives override earlier ones so this works as intended, but LLVM 12
turned this into a warning as there's no good reason to do such a thing
and could be a potential bug. Thus, remove the redundant and incorrect
.globl directive for fw_platform_init.

Signed-off-by: Jessica Clarke <jrtc27@jrtc27.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

lib: sbi: Fix sbi_pmu_exit() for systems not having MCOUNTINHIBIT csr

The sbi_pmu_exit() crashes on systems not having MCOUNTINHIBIT csr
so to fix this we check SBI_HART_HAS_MCOUNTINHIBIT feature in
sbi_pmu_exit() and do nothing if it is not available.

Fixes: 13d40f21d588 ("lib: sbi: Add PMU support")
Signed-off-by: Anup Patel <anup.patel@wdc.com>

firmware: Define a macro for version of struct fw_dynamic_info

Avoid using a magic number, instead use a macro for the version of
struct fw_dynamic_info.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Xiang W <wxjstz@126.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

firmware: Remove the sanity checks in fw_save_info()

The sanity checks on the magic and version was already done in
fw_boot_hart(), which happens before fw_save_info() is called.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Xiang W <wxjstz@126.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

docs: Make <xyz> visible in the rendered platform guide

At present in the rendered platform guide, all instances of <xyz>
are missing. Use &lt; and &gt; to replace <> to make them visible.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Xiang W <wxjstz@126.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

docs: Correct a typo in platform_guide.md

It's riscv-pk, not riskv-pk.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Xiang W <wxjstz@126.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

firmware: Minor optimization in _scratch_init()

Before entering _scratch_init(), register t3 already holds a copy
of the firmware end address, hence there is no need to calculate
it again. This reduces 3 instructions in each _scratch_init() loop.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Xiang W <wxjstz@126.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

platform: generic: Add PMU support

Add PMU support for generic platform. Generic platform solely relies on
the device tree to parse all pmu related information. If any event is
not described in device tree, generic platform will not support it.

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

lib: sbi: Improve TLB function naming

Follow the standard conventon for static function names:

All global functions should be start with sbi_<module name>_
All static functions should be start with <module name>_

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

lib: sbi: Implement firmware counters

RISC-V SBI v0.3 specification defines a set of firmware events that can
provide additional information about the current firmware context. All
of the firmware event monitoring are enabled now. The firmware
events must be defined as raw perf event with MSB set as specified in the
specification.

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

lib: sbi: Implement SBI PMU extension

RISC-V SBI specfication 0.3 defines a PMU extension that allows supervisor
mode to start/stop/configure pmu related events. This patch implements
all of the functionality defined in the specification.

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

utils: fdt: Add fdt helper functions to parse PMU DT nodes

The PMU DT node bindings are defined in docs/pmu_support.md
Add few fdt helper functions to parse the DT node and update the
event-counter mapping tables.

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

lib: sbi: Add PMU support

RISC-V SBI v0.3 specification defined a PMU extension to configure/start/stop
the hardware/firmware pmu events.

Implement PMU support in OpenSBI library. The implementation is agnostic of
event to counter mapping & mhpmevent value configuration. That means, it
expects platform hooks will be used to set up the mapping and provide
the mhpmevent value at runtime.

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

lib: sbi: Add PMU specific platform hooks

A platform hook to initialize PMU allows platform vendors to provide
their own mechanism to define pmu event-counter mappings in addition
to the DT based approach.

Another platform hook that allows platform vendors customize the
final mhpmevent value configuration.

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

lib: sbi: Use csr_read/write_num to read/update PMU counters

Currently, csr_read/write_num functions are used to read/write PMP related
CSRs where CSR value is decided at runtime. Expand this function to include
PMU related CSRs as well.

Reviewed-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Xiang W <wxjstz@126.com>
Signed-off-by: Atish Patra <atish.patra@wdc.com>

lib: sbi: Remove redundant boot time print statement

This patch removes redundant print from sbi_boot_print_hart().

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

include: Add a list empty check function

Implement a list helper function that checks for empty lists.

Reviewed-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Xiang W <wxjstz@126.com>
Signed-off-by: Atish Patra <atish.patra@wdc.com>

lib: sbi: Disable m/scounteren & enable mcountinhibit

Currently, all bits in mcountern are enabled unconditionally at boot time.
With SBI PMU extension, all the programmable counters should enabled only
during performance monitoring for a particular event. However, this is done
only if mcountinhibit is implemented because the supervisor mode can not
start/stop any event without mcountinhibit.

Similarly, supervisor should take care enabling scounteren which allows
U-mode to access programmable pmu counters. All the non-programmable ones
(CY, TM, IR) should be enabled in M-mode because some userspace may rely on
builtins such as __builtin_readcyclecounter. Supervisor OS can still disable
them during initial configuration.

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

lib: sbi: Detect number of bits implemented in mhpmcounter

RISC-V privilege specification allows the implementation to have less
than 64 bits.

Add a function to detect the number of implemented bits in mhpmcounter
dynamically at runtime.

Reviewed-by: Xiang W <wxjstz@126.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
Signed-off-by: Atish Patra <atish.patra@wdc.com>

lib: sbi: Remove stray '\' character

Reviewed-by: Xiang W <wxjstz@126.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
Signed-off-by: Atish Patra <atish.patra@wdc.com>

lib: sbi: Detect mcountinihibit support at runtime

RISC-V ISA specification v1.11 defined mcountinhibit CSR that allows
software to stop any counter from incrementing. The SBI PMU extension
depends on this CSR support in hardware.

Define mcountinhibit as a hart specific feature and detect it at runtime.

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

docs: Add device tree bindings for SBI PMU extension

SBI PMU extension requires a firmware to be aware of the event to
counter/mhpmevent mappings supported by the hardware. One approach
is to encode that information in the device tree.

Define a device tree binding that allows a hardware to describe
all the PMU mappings required in concise format.

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

platform: generic: Terminate platform.name with null

fw_platform_init() fills platform.name without considering the
ending null character. Fix it.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

docs/platform: thead-c9xx: Remove FW_PIC=y

FW_PIC is on by default. Hence no need to explicitly require it.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

lib: utils: reset: unify naming of 'sifive_test' device

Unify all the file and function names of 'sifive_test' device, to use
the same prefix. This is also a preparatory patch for upcoming sifive
reset device.

Signed-off-by: Green Wan <green.wan@sifive.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

platform: Replace CLINT library usage with ACLINT library

The ACLINT devices are backward compatible with SiFive CLINT
so we replace all CLINT library usage in various platforms
with ACLINT library. As a result of this replacement, the
CLINT library is not used by any part of OpenSBI hence we
remove it.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Xiang W <wxjstz@126.com>

lib: utils/timer: Add FDT based ACLINT MTIMER driver

We add a new FDT based ACLINT MTIMER driver which works for
both CLINT device and standalone ACLINT MTIMER device.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Xiang W <wxjstz@126.com>

lib: utils/ipi: Add FDT based ACLINT MSWI IPI driver

We add a new FDT based ACLINT MSWI IPI driver which works for both
CLINT device and standalone ACLINT MSWI device.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Xiang W <wxjstz@126.com>

lib: utils: Add FDT parsing API common for both ACLINT and CLINT

We add fdt_parse_aclint_node() which can parse both ACLINT and
CLINT DT nodes. This means fdt_parse_clint_node() is not required
anymore 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: Xiang W <wxjstz@126.com>

lib: utils/ipi: Add ACLINT MSWI library

We add common ACLINT MSWI library similar to the CLINT library
so that OpenSBI platforms can use it.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Xiang W <wxjstz@126.com>

lib: utils/timer: Add ACLINT MTIMER library

We add common ACLINT MTIMER library similar to the CLINT library
so that OpenSBI platforms can use it.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Xiang W <wxjstz@126.com>

lib: simplify sbi_fifo_inplace_update()

Don't assign an unused value to variable index.

Use operator '-=' where applicable.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Xiang W <wxjstz@126.com>

lib: sign conflict in wake_coldboot_harts()

Compiling wake_coldboot_harts() with GCC 11 and -Wextra yields:

lib/sbi/sbi_init.c:208:27:
error: comparison of integer expressions of different signedness:
‘int’ and ‘u32’ {aka ‘unsigned int’} [-Werror=sign-compare]
  208 |         for (int i = 0; i <= sbi_scratch_last_hartid(); i++) {
      |                           ^~

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Xiang W <wxjstz@126.com>

lib: sign conflict in sbi_tlb_entry_process()

Compiling sbi_tlb_entry_process() with GCC 11 and -Wextra yields:

lib/sbi/sbi_tlb.c: In function ‘sbi_tlb_process_count’:
lib/sbi/sbi_tlb.c:206:31:
error: comparison of integer expressions of different signedness:
‘u32’ {aka ‘unsigned int’} and ‘int’ [-Werror=sign-compare]
  206 |                 if (deq_count > count)

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Xiang W <wxjstz@126.com>

lib: utils/libfdt: Upgrade to v1.6.1 release

Sync with libfdt v1.6.1 release source codes.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

lib: sbi: Fix GET_F64_REG inline assembly

Current, GET_F64_REG() macro does not generate correct inline
assembly for the RV32 systems. This patch provides separate
definitions of GET_F64_REG() macro for RV32 and RV64 systems.

Signed-off-by: Charles Papon <charles.papon.90@gmail.com>
Signed-off-by: Anup Patel <anup.patel@wdc.com>

lib: utils: missing initialization in thead_reset_init

If property csr-copy does not exist, fdt_getprop() will return NULL and cnt
will have a random value from the stack.

Call clone_csrs() only if cnt is initialized to a non-zero value.

Fixes: 49e422c5ad7a ("lib: utils: reset: Add T-HEAD sample platform reset driver")
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

lib: sbi_scratch: zero out scratch memory on all harts

In sbi_scratch_init() we determine the last hart. The index of the last
hart cannot exceed SBI_HARTMASK_MAX_BITS - 1. We should not initialize
last_hartid_having_scratch to a higher number to avoid buffer overflows
when using this value before calling sbi_scratch_init().

When allocating scratch memory in sbi_scratch_alloc_offset() we zero out
the allocated memory for all harts except for the last one. We should not
skip the last hart.

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

platform: andes/ae350: Drop plicsw_ipi_sync()

plicsw_ipi_sync() is a forward declaration but without the actual
implementation. Drop it.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

platform: andes/ae350: Drop plicsw_get_pending()

This is not used anywhere. Drop it.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

docs/platform: andes-ae350: Fix missing spaces

Fix several places in the docmentation that are missing spaces.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

platform: andes/ae350: Cosmetic fixes in plicsw.c

- %s/CLINT/PLICSW
- replace '.' with a space
- add a space around * in plicsw_cold_ipi_init()

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

lib: sbi_scratch: remove owner from sbi_scratch_alloc_offset

The parameter owner of function sbi_scratch_alloc_offset() is never used.
The scratch memory is small. We should not use it for debug information in
future. Hence eliminate the parameter.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: Xiang W <wxjstz@126.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

lib: utils: consider ':' in stdout-path

The value of the /chosen/stdout-path devicetree property is used to
determine the UART used by openSBI. According to the devicetree
specification the value may contain a hyphen, e.g.

chosen {
                stdout-path = "/serial@f00:115200";
        };

If the character ':' is present, it terminates the path of the device.

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

docs: debugging OpenSBI

Describe how to debug OpenSBI on QEMU with GDB.

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

lib: utils: Try other FDT drivers when we see SBI_ENODEV

We should try other FDT drivers when we see SBI_ENODEV returned
by cold_init() of FDT driver.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Xiang W <wxjstz@126.com>

lib: Check region base for merging in sbi_domain_root_add_memregion()

We can merge region B onto region A only if base of region A is
aligned to region A order + 1.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Xiang W <wxjstz@126.com>

lib: utils/fdt: Replace strcmp with strncmp

Use strncmp() instead of strcmp() in __fixup_find_domain_offset()
so that it compiles fine when linking with external firmware (such
as EDK2).

Signed-off-by: Daniel Schaefer <daniel.schaefer@hpe.com>
Reviewed-by: Xiang W <wxjstz@126.com>
Reviewed-by: Abner Chang <abner.chang@hpe.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

lib: utils/fdt: Don't use sbi_string functions

When SBI is built by external firmware, we need to use their functions,
defined in libfdt_env.h.

Just like 2cfd2fc9048806353298a1b967abf985901e36e8

Signed-off-by: Daniel Schaefer <daniel.schaefer@hpe.com>
Reviewed-by: Abner Chang <abner.chang@hpe.com>
Reviewed-by: Xiang W <wxjstz@126.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

lib: utils: Add strncpy macro to libfdt_env.h

we want to use sbi_strncpy as strncpy in the OpenSBI implementation for
libfdt.

Just like 2845d2d2cf4fb74a89452ba223995aa4a118c07e

Signed-off-by: Daniel Schaefer <daniel.schaefer@hpe.com>
Reviewed-by: Abner Chang <abner.chang@hpe.com>
Reviewed-by: Xiang W <wxjstz@126.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

Makefile: unconditionally disable SSP

Though -nostdlib is passed in CFLAGS, -fno-stack-protector must also be
passed to avoid linking errors related to undefined references to
'__stack_chk_guard' and '__stack_chk_fail' if toolchain enforces
-fstack-protector.

Fixes:
 - https://gitlab.com/kubu93/buildroot/-/jobs/1247043359

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Xiang W <wxjstz@126.com>

lib: utils/serial: Support Synopsys DesignWare APB UART

Synopsys DesignWare APB UART is seen on the StarFive JH7100 SoC.
Its programming interface is compatible with the existing 8250
UART driver. Simply add its compatible string to the driver makes
it work with the StarFive JH7100 SoC on a BeagleV board.

With this patch, the generic platform firmware can be used out of
the box on the BeagleV board.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

lib: sbi: Have spinlock checks return bool

spin_lock_check already returned bool in the source file but not in the
header. With some toolchains that causes an error, as it should.

Because it and related functions all essentially return a bool, we can
use this opportunity to change them.

Signed-off-by: Daniel Schaefer <git@danielschaefer.me>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

platform: Remove sifive/fu540 platform

Now that SiFive HiFive Unleashed board is using the generic platform
support in OpenSBI, let's remove the old non-generic one.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

docs: platform: Describe sifive_fu540 as supported generic platform

The upstream U-Boot/QEMU have been using generic platform for SiFive
HiFive Unleashed board for some time. Let's document sifive_fu540 as
one of the supported targets for "generic" platform.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

docs: platform: Sort platform names

Let's sort the platform names in alphabetical order.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

lib: utils/serial: Add support for Gaisler APBUART

This patch adds support for the UART used by the NOEL-V processor.

Cobham Gaisler's NOEL-V RISC-V processor IP is available under GPL
and commercial license and is described in more detail at
https://www.gaisler.com/noelv.

Signed-off-by: Daniel Cederman <cederman@gaisler.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

docs/platform: sifive_fu540: Update U-Boot defconfig name

With latest U-Boot upstream (v2021.07 in development), the defconfig
name has been changed to sifive_unleashed_defconfig. Update the doc.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

lib: sbi: Show devices provided by platform in boot prints

We extend the boot-time prints to show various devices provided
(or registered) by the platform support. This will help users
verify hardware devices available for OpenSBI firmwares.

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

lib: sbi: Simplify HSM platform operations

Instead of having hsm_start(), hsm_stop() and hsm_suspend()
callbacks in platform operations, it will be much simpler for
HSM driver to directly register these operations as a device
to the sbi_hsm implementation.

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

lib: sbi: Simplify system reset platform operations

Instead of having system_reset_check() and system_reset() callbacks
in platform operations, it will be much simpler for reset driver to
directly register these operations as a device to the sbi_system
implementation.

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

lib: sbi: Simplify ipi platform operations

Instead of having ipi_send() and ipi_clear() callbacks in
platform operations, it will be much simpler for ipi driver
to directly register these operations as a device to sbi_ipi
implementation.

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

lib: sbi: Simplify timer platform operations

Instead of having timer_value(), timer_event_start(), and
timer_event_stop() callbacks in platform operations, it will
be much simpler for timer driver to directly register these
operations as device to the sbi_timer implementation.

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

lib: sbi: Simplify console platform operations

Instead of having console_putc() and console_getc() callbacks in
platform operations, it will be much simpler for console driver to
directly register these operations as device to the sbi_console
implementation.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Xiang W <wxjstz@126.com>

lib: sbi: Remove domains_root_regions() platform callback

We now have sbi_domain_root_add_memregion() which allows platform
support to add root domain regions at boot-time so let's remove
the domains_root_regions() platform callback which was added
for this purpose.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Xiang W <wxjstz@126.com>

docs: generic: Add T-HEAD C9xx series processors

Add description and dts examples for T-HEAD C9xx platforms.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

platform: Remove platform/thead

We could use platform/generic instead, and won't use
platform/thead/c910 again.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

firmware: Enable FW_PIC by default

Let's have FW_PIC enabled by default so that OpenSBI firmware
can by default run from any physical address.

Tested with qemu_rv32 & rv64, T-HEAD all hardwares.

Suggested-by: Anup Patel <anup.patel@wdc.com>
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Tested-by: Guo Ren <guoren@linux.alibaba.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

lib: sbi: Fix sbi_domain_root_add_memregion() for merging memregions

We should decrement root_memregs_count by one after merging two
memregions otherwise new memregion added after a merge will be
appended after last sentinel memregion of zero order.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Xiang W <wxjstz@126.com>

lib: utils: reset: Add T-HEAD sample platform reset driver

This driver is for T-HEAD test chip, fpga. It could work with
all T-HEAD riscv processors: C9xx series.

example1: (Using io-regs for reset)
reset: reset-sample {
compatible = "thead,reset-sample";
plic-delegate = <0xff 0xd81ffffc>;
entry-reg = <0xff 0xff019050>;
entry-cnt = <4>;
control-reg = <0xff 0xff015004>;
control-val = <0x1c>;
csr-copy = <0x7f3 0x7c0 0x7c1 0x7c2 0x7c3 0x7c5 0x7cc>;
};

example2: (Using csr-regs for reset)
reset: reset-sample {
compatible = "thead,reset-sample";
plic-delegate = <0xff 0xd81ffffc>;
using-csr-reset;
csr-copy = <0x7c0 0x7c1 0x7c2 0x7c3 0x7c5 0x7cc
    0x3b0 0x3b1 0x3b2 0x3b3
    0x3b4 0x3b5 0x3b6 0x3b7
    0x3a0>;
};

example3: (Only delegate plic enable to S-mode)
reset: reset-sample {
compatible = "thead,reset-sample";
plic-delegate = <0xff 0xd81ffffc>;
};

After this patch, all T-HEAD c9xx would use platform/generic with fw_dynamic
as default:

CROSS_COMPILE=riscv64-linux-gnu- PLATFORM=generic FW_PIC=y /usr/bin/make

The platform/thead will be deprecated.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

lib: utils: Implement "64bit-mmio" property parsing

Figure out CLINT has_64bit_mmio from DT node and using antonym for
compatibility.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

lib: sbi: Make sbi_domain_memregion_initfw() a local function

The sbi_domain_memregion_initfw() is no longer used outside
sbi_domain.c so let's make it a local function.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Xiang W <wxjstz@126.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>

lib: utils: Copy over restricted root domain memregions to FDT domains

We should copy over all restricted memregions from the root domain
to the domains populated from FDT. These restricted root memregions
are typically firmware memregion and M-mode only mmio memregions.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Xiang W <wxjstz@126.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>

lib: sbi: Make the root domain instance global variable

We make the the root domain instance global variable so that
platform support and drivers can iterate over the root domain
regions.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Xiang W <wxjstz@126.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>

lib: utils/sys: Add CLINT memregion in the root domain

The CLINT memory should not be accessed by the supervisor-mode
software so let's protect it by adding CLINT memregion to the
root domain.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Xiang W <wxjstz@126.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>

lib: sbi: Add sbi_domain_root_add_memregion() API

We should allow platform support to add more root memory regions
before domains are finalized. This will help platform support to
protect critical M-mode only resources.

This patch adds sbi_domain_root_add_memregion() API for above
described purpose.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Xiang W <wxjstz@126.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>

lib: sbi: Add sbi_domain_memregion_init() API

This patch adds sbi_domain_memregion_init() helper API which can
be used by platform support to initialize a domain memory region
before adding it to the root domain.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Xiang W <wxjstz@126.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>

lib: sbi: Domains can be registered only before finalizing domains

The domains are boot-time system-level partitions so we should
allow platform support to register domains only before hart
domain assignments are finalized.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Xiang W <wxjstz@126.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>

docs: fix link to OpenPiton documentation

Updates link in platforms documentation to point to the correct
OpenPiton document.

Signed-off-by: hasheddan <georgedanielmangum@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

lib: sbi: fix atomic_add_return

The unsigned length may be 4 bytes or 8 bytes, amoadd.w only applies
to 4 bytes hence this patch.

Signed-off-by: Xiang W <wxjstz@126.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

lib: sbi: Replace test-and-set locks by ticket locks

Replace the test-and-set spinlock implementation with ticket locks
in order to get fairness (in form of FIFO order).

The implementation uses a 32-bit wide struct, which consists of
two 16-bit counters (owner and next). This is inspired by similar
spinlock implementations on other architectures.
This allows that the code works for both, RV32 and RV64.

Signed-off-by: Christoph Muellner <cmuellner@linux.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Xiang W <wxjstz@126.com>

include: sbi: Allow direct initialization via SPIN_LOCK_INIT()

The current implementation of SPIN_LOCK_INIT() provides the spinlock
to be initialized as reference. This does not allow a direct
initialization of the spinlock object at the creation site.

Let's pass the spinlock directly instead (like Linux does as well)
and adjust all users of the macro (in fact there is only one user).

Signed-off-by: Christoph Muellner <cmuellner@linux.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

include: types: Add __aligned(x) to define the minimum alignement

The __aligned(x) macro is a common wrapper around compiler's
aligned attribute, which allow to define the minimum alignement
of a data type. Let's add this macro.

Signed-off-by: Christoph Muellner <cmuellner@linux.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

firmware: Remove redundant add instruction from trap restore path

The "add sp, a0, zero" instruction in the trap restore path is redundant
and can be avoided if TRAP_RESTORE_xyz() assembly macros use a0 as the
base register instead of sp.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Xiang W <wxjstz@126.com>

lib: fix csr detect support

csr_read_allowed/csr_read_allowed requires trap.case to detect the results,
but if no exception occurs, the value of trap.case will remain unchanged,
which makes the detection results unreliable. Add code to initialize
trap.case to 0.

Signed-off-by: Xiang W <wxjstz@126.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

firware: optimize the exception exit code

There are two copies of the same abnormal exit code, this patch deletes one

Signed-off-by: Xiang W <wxjstz@126.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

lib/utils: Support fixing up the official DT bindings of PLIC

Current fdt_plic_fixup() only does necessary fix-up against the legacy
"riscv,plic0" node. The upstream Linux kernel defines its official DT
bindings which uses "sifive,plic-1.0.0" as the compatible string and
we should check that first, and if not present fall back to legacy.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

lib/utils: Drop the 'compat' parameter of fdt_plic_fixup()

At present fdt_plic_fixup() accepts a 'compat' parameter for PLIC
compatible string. In preparation to support the new DT bindings,
drop this and use "riscv,plic0" directly in fdt_plic_fixup().

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

lib/utils: Support the official clint DT bindings

Linux kernel commit a2770b57d083 ("dt-bindings: timer: Add CLINT bindings")
adds the official DT bindings for CLINT, which uses "sifive,clint0"
as the compatible string. "riscv,clint0" is now legacy and has to
be kept for backward compatibility of legacy systems.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>

include: headers: Replace __ASSEMBLY__ with __ASSEMBLER__

GCC has already a predefined macro __ASSEMBLER__ therefore, it can be
used without the need to define a new flag with -D__ASSEMBLY__.
This is useful when adding the library to projects having a build
system such one can build without the need to make changes.
THe build system does not use the Makefile in the sources tree.

Signed-off-by: Marouene Boubakri <marouene.boubakri@nxp.com>
Signed-off-by: Anup Patel <anup.patel@wdc.com>

lib: sbi: illegal CSR 0x306 access in hpm_allowed()

The trap handler sbi_emulate_csr_read() invokes hpm_allowed() which reads
CSR 0x306 (mcounteren). The K210 does not support CSR 0x306. While trying
to handle a trap occurring in S-mode code this creates an additional trap
in M-mode. This results in failure to redirect to S-mode and the system
hanging in sbi_hart_hang().

In hart_detect_features() we have already determined if CSR 0x306 is
available and stored that information in the scratch area. We can use this
information to decide if CSR 0x306 shall be accessed in hpm_allowed() and
thus avoid the M-mode trap.

Likewise if CSR scounteren is not available we have to avoid reading CSR
0x106.

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

firmware: Support position independent execution

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>

firmware: Use lla to access all global symbols

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>

include: sbi: SBI function IDs for RFENCE extension

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>

lib: Remove redundant sbi_platform_ipi_clear() calls

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>

include: sbi: Upgrade SBI implementation version to v0.3

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>

lib: sbi: Implement SBI HSM suspend function

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>

include: sbi: Add hart_suspend() platform callback

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>

lib: sbi: Add sbi_hart_reinit() function

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>