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2020-12-01lib: sbi: Implement System Reset (SRST) SBI extensionAnup Patel3-0/+64
The SBI SRST extension has been accepted and merged in the latest SBI v0.3-draft specification. (Refer, https://github.com/riscv/riscv-sbi-doc) It allows to S-mode software to request system shutdown, cold reboot, and warm reboot. This patch implements SBI SRST extension as a replacement of the legacy sbi_shutdown() call of SBI v0.1 specification. Signed-off-by: Anup Patel <anup.patel@wdc.com> Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-12-01lib: sbi: Improve system reset platform operationsAnup Patel17-36/+137
To implement the SBI SRST extension, we need two platform operations for system reset: 1) system_reset_check() - This operation will check whether given reset type and reason are supported by the platform 2) system_reset() - This operation will do the actual platform system reset and it will not return if reset type and reason are supported by the platform This patch updates system reset related code everywhere as-per above. Signed-off-by: Anup Patel <anup.patel@wdc.com> Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-12-01platform: Remove dummy system reset functionsAnup Patel5-49/+0
Few platforms have dummy system reset functions so let's remove these dummy system reset functions to allow generic code deal with it in the right way. 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>
2020-12-01include: sbi: Remove opensbi specific reset type definesAnup Patel5-10/+8
We can now use the standard SBI SRST extension reset types instead of the opensbi specific (SBI_PLATFORM_RESET_xyz) reset types hence remove related opensbi specific defines. The "platform_" prefix of the reset type parameter of sbi_system_reset() function should also be removed. 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>
2020-12-01include: sbi: Add SBI SRST extension related definesAnup Patel1-0/+12
We extend the SBI ecall interface header for the SBI SRST extension recently accepted in SBI specification v0.3-draft. 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>
2020-11-27docs: fix a typo errorYuan Li1-1/+1
fix a typo error in docs/platform/sifive_fu540.md Signed-off-by: Yuan Li <dskwelmcy@163.com> Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-11-10lib: sbi: Improve boot prints in cold boot sequenceAnup Patel1-21/+69
Currently, we have all boot prints at the end of cold boot sequence which means if there is any failure in cold boot sequence before boot prints then we don't get any print. This patch improves boot prints in cold boot sequence as follows: 1. We divide the boot prints into multiple parts and print it from different locations after sbi_console_init() 2. We throw an error print if there is any failure in cold boot sequence after sbi_console_init() Signed-off-by: Anup Patel <anup.patel@wdc.com> Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-11-02Makefile: Add option to use toolchain default ABI and ISA stringAnup Patel1-4/+14
When PLATFORM_RISCV_ABI and PLATFORM_RISCV_ISA are not specified, we force "-mabi=lp64 -march=rv64gc" for RV64 and force "-mabi=ilp32 -march=rv32gc" for RV32. This can prevent users from using the toolchain default "-mabi" and "-march" options. To allow using toolchain defaults, we add compile-time option PLATFORM_RISCV_TOOLCHAIN_DEFAULT which when enabled forces the top-level makefile to use toolchain default ABI and ISA string. To enable the option, pass "PLATFORM_RISCV_TOOLCHAIN_DEFAULT=1" to top-level make. Reported-by: Alistair Francis <alistair.francis@wdc.com> Signed-off-by: Anup Patel <anup.patel@wdc.com> Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
2020-10-26lib: sbi: Improve boot time print with additional PMP informationAtish Patra1-14/+23
We know about pmp granularity and number of bits supported by PMP. Show those information in the boot time info print Signed-off-by: Atish Patra <atish.patra@wdc.com> Reviewed-by: Anup Patel <anup.patel@wdc.com>
2020-10-26lib: sbi: Detect PMP granularity and number of address bitsAtish Patra2-4/+60
As per RISC-V privilege specification, a platform may choose to implement a coarser granularity scheme for PMP addresses. In that case, we shouldn't allow any pmp region size smaller than the platform supports. A platform may not also implement all the bits for a PMP address specified in the priv specification. The pmp range granularity and address bits should be detected dynamically before detecing PMP regions. Any pmp modification request beyond these detected value must not succeed. Signed-off-by: Atish Patra <atish.patra@wdc.com> Reviewed-by: Anup Patel <anup.patel@wdc.com>
2020-10-23lib: utils: Implement "ranges" property parsingAtish Patra1-2/+48
The "reg" property in a device node may not be the correct address always. If a parent node defines a "ranges" property, the child address need to be translated with respect to parents address. If the ranges property is not present, it will just use 1:1 translation. Signed-off-by: Atish Patra <atish.patra@wdc.com> Reviewed-by: Anup Patel <anup.patel@wdc.com>
2020-10-21docs: Add initial documentation for domain supportAnup Patel3-0/+110
We add initial documentation for OpenSBI domain support to help RISC-V platform vendors achieve system-level partitioning. Signed-off-by: Anup Patel <anup.patel@wdc.com> Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-10-21lib: sbi: Display domain details in boot printsAnup Patel5-48/+127
We extend boot prints to display details of each domain. In the process, we remove sbi_hart_pmp_dump() because it shows redundant information which domain details already show. Signed-off-by: Anup Patel <anup.patel@wdc.com> Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-10-20lib: sbi: Configure PMP based on domain memory regionsAnup Patel1-15/+22
The PMP configuration on each HART should be only based on the memory regions of the assigned domain because each domain includes a memory region to protect the underlying firmware. This patch updates the sbi_hart_pmp_configure() function accordingly. Signed-off-by: Anup Patel <anup.patel@wdc.com> Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-10-20lib: sbi: Remove redundant sbi_hart_pmp_xyz() functionsAnup Patel2-48/+0
The sbi_hart_pmp_get() and sbi_hart_pmp_check_addr() functions are not used anymore hence this patch removes these functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-10-20lib: utils: Update fdt_cpu_fixup() to use current domainAnup Patel1-5/+3
The fdt_cpu_fixup() should disable a HART in DT if the HART is not assigned to the current HART domain. This patch updates fdt_cpu_fixup() accordingly. Signed-off-by: Anup Patel <anup.patel@wdc.com> Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-10-20lib: utils: Update fdt_reserved_memory_fixup() to use current domainAnup Patel1-25/+22
Now that each HART is mapped to a domain having a set of memory regions, we update fdt_reserved_memory_fixup() to use domain memory regions for adding reserved memory nodes in device tree. We also change reserved memory node name prefix from "mmode_pmp" to "mmode_resv" because domain memory regions can impact other hardware configurations (such as IOPMP, etc) along with PMP. Signed-off-by: Anup Patel <anup.patel@wdc.com> Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-10-20lib: sbi: Extend sbi_system_reset() for domainsAnup Patel1-3/+4
The sbi_system_reset() should issue platform system reset only if domain of current HART is allowed to do system reset. This patch extends sbi_system_reset() as-per above. Signed-off-by: Anup Patel <anup.patel@wdc.com> Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-10-20lib: sbi: Optimize sbi_hsm_hart_started_mask() implementationAnup Patel1-12/+22
Instead of calling sbi_hsm_hart_get_state() in a loop, we can simply call a new inline __sbi_hsm_hart_get_state() which only takes "hartid" and enforce domain checks using sbi_domain_assigned_hartmask(). This patch optimizes sbi_hsm_hart_started_mask() as-per above. Signed-off-by: Anup Patel <anup.patel@wdc.com> Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-10-20lib: sbi: Extend sbi_hsm_hart_start() for domainsAnup Patel4-15/+19
The sbi_hsm_hart_start() should consider the domain under which we are trying to start the HART. This will help ensure that HART A can start HART B only if both HARTs A and B belong to the same domain. We also have a special case when we bring-up boot HART of non-root domains in sbi_domain_finalize() where we should skip domain checks in sbi_hsm_hart_start(). To achieve this, sbi_hsm_hart_start() should do domain checks only when domain parameter is non-NULL. This patch extends sbi_hsm_hart_start() as-per above. Signed-off-by: Anup Patel <anup.patel@wdc.com> Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-10-20lib: sbi: Extend sbi_hsm_hart_started_mask() for domainsAnup Patel6-15/+27
The sbi_hsm_hart_started_mask() API should take one more parameter to allow caller specify domain under which started_mask is being generated. Further, the sbi_hsm_hart_started_mask() depends on sbi_hsm_hart_get_state() which also should return HART state under specified domain. This patch updates both sbi_hsm_hart_started_mask() and sbi_hsm_hart_get_state() as-per above. Signed-off-by: Anup Patel <anup.patel@wdc.com> Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
2020-10-20lib: sbi: Add initial domain supportAnup Patel5-0/+568
An OpenSBI domain is a logical entity representing a set of HARTs and a set of memory regions for these HARTs. The OpenSBI domains support will allow OpenSBI platforms and previous booting stage (i.e. U-Boot SPL, Coreboot, etc) to partition a system into multiple domains where each domain will run it's own software. For inter-domain isolation, OpenSBI will eventually use various HW features such as PMP, ePMP, IOPMP, SiFive shield, etc but initial implementation only use HW PMP support. This patch provides initial implementation of OpenSBI domains where we have a root/default domain and OpenSBI platforms can provide non-root/custom domains using domain_get() callback. 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>
2020-10-20include: sbi: Make hartmask pointer const in sbi_hartmask_test_hart()Anup Patel1-1/+1
The sbi_hartmask_test_hart() does not modify hartmask so the hartmask pointer parameter should be declared const. Signed-off-by: Anup Patel <anup.patel@wdc.com> Reviewed-by: Atish Patra <atish.patra@wdc.com> Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
2020-10-20lib: sbi: Remove redundant hartid parameter from sbi_hart_init()Anup Patel3-10/+10
The hartid parameter of sbi_hart_init() is not used anywhere in sbi_hart_init() implementation so let's remove it. Signed-off-by: Anup Patel <anup.patel@wdc.com> Reviewed-by: Atish Patra <atish.patra@wdc.com> Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
2020-10-20lib: sbi: Configure PMP late in coldboot and warmboot pathAnup Patel3-2/+11
We factor-out PMP configuration from sbi_hart_init() as a separate sbi_hart_pmp_configure() function and do the PMP configuration very late in coldboot and warmboot path just before platform_final_init(). Eventually, this enable us to configure PMP totally based on OpenSBI domain where OpenSBI domains can be parsed from device-tree in any of the platform operations except platform_final_init(). Signed-off-by: Anup Patel <anup.patel@wdc.com> Reviewed-by: Atish Patra <atish.patra@wdc.com> Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
2020-10-20include: sbi: Remove pmp_region callbacks from sbi_platform_operationsAnup Patel2-63/+1
The pmp_region_xyz() callbacks are not required in sbi_platform_operations because we will be using OpenSBI domain memory regions to program the PMP CSRs. Signed-off-by: Anup Patel <anup.patel@wdc.com> Reviewed-by: Atish Patra <atish.patra@wdc.com> Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
2020-10-20include: sbi: Remove redundant includes from sbi_platform.hAnup Patel2-2/+3
The sbi_ecall.h and sbi_trap.h are not required to be included in sbi_platform.h hence we remove it. This way sources requiring these headers will have to explicitly include it thereby reducing implicit includes. Signed-off-by: Anup Patel <anup.patel@wdc.com> Reviewed-by: Atish Patra <atish.patra@wdc.com> Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
2020-10-18platform: kendryte/k210: Add some padding for FDT fixupsAnup Patel1-0/+1
The Kendryte K210 platform has built-in DTB and does not provides FW_PAYLOAD_FDT_ADDR. This means the FDT fixups will be done on the built-in DTB in absence of FW_PAYLOAD_FDT_ADDR. This patch adds some padding in built-in DTB for FDT fixups. Signed-off-by: Anup Patel <anup.patel@wdc.com> Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-10-18Makefile: Allow padding zeros when converting DTB to C sourceHeinrich Schuchardt2-3/+13
We extend d2c.sh to allow padding zeros in output C source when converting DTB to C source. Using this feature, platforms can create extra room for in-place FDT fixups on built-in DTBs. Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de> Signed-off-by: Anup Patel <anup.patel@wdc.com> Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-10-18firmware: Remove FW_PAYLOAD_FDT_PATH compile-time optionAnup Patel11-79/+12
The FW_PAYLOAD_FDT_PATH compile-time option is replaced by FW_FDT_PATH compile-time option which is more flexible and common across all OpenSBI firmwares. This patch removes FW_PAYLOAD_FDT_PATH and updates related documentation to use FW_FDT_PATH. Signed-off-by: Anup Patel <anup.patel@wdc.com> Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-10-18firmware: Add common FW_FDT_PATH compile-time optionAnup Patel4-5/+38
Currently, only FW_PAYLOAD has mechanism to embed external FDT using FW_PAYLOAD_FDT_PATH compile-time option. This patch adds a common FW_FDT_PATH compile-time option to embed external FDT for all OpenSBI firmwares (i.e FW_JUMP, FW_PAYLOAD, and FW_DYNAMIC). Signed-off-by: Anup Patel <anup.patel@wdc.com> Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-10-18Makefile: Build ELF, BIN and LD script in platform build directoryAnup Patel1-9/+9
Currently, the make rules for ELF, BIN and LD script are little generic to allowing ELF, BIN and LD script to be anywhere in the build directory. For OpenSBI firmwares, the ELF, BIN, and LD script are always platform specific so we update make rules accordingly. Signed-off-by: Anup Patel <anup.patel@wdc.com> Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-10-10makefile: fix clean directiveDamien Le Moal1-0/+2
Add cleaning of compiled device tree files (.dtb files). Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> Reviewed-by: Anup Patel <anup.patel@wdc.com>
2020-10-02lib: sbi_scratch: typo scatchHeinrich Schuchardt1-1/+1
%s/scatch/scratch Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de> Reviewed-by: Anup Patel <anup.patel@wdc.com>
2020-09-25lib: sbi: Fix PMP CSR detectionPragnesh Patel1-1/+1
HiFive unleashed currently implements fewer than 56 bits of physical address so existing PMP CSR detection is broken. PMP address register encodes bits 55-2 of a 56-bit physical address, Not all physical address bits may be implemented, So just check minimum 1 bit. Fixes: 74d1db706293 ("lib: sbi: Improve PMP CSR detection and progamming") Signed-off-by: Pragnesh Patel <pragnesh.patel@sifive.com> Reviewed-by: Atish Patra <atish.patra@wdc.com> Reviewed-by: Anup Patel <anup.patel@wdc.com>
2020-09-16platform: generic: Don't mark non-MMU HARTs as invalidAnup Patel1-5/+1
Currently, the generic platform fw_platform_init() marks non-MMU HARTs (e.g. E-core on SiFive Unleashed) as invalid. This means such non-MMU HARTs won't be allowed to go ahead by sbi_init(). The sbi_init() now has a check for next stage privilege mode when selecting coldboot HART. This check will force non-MMU HARTS (i.e. HARTs without S-mode) to proceed in warmboot path and wait in the HSM STOPPED state. This means we don't need to mark non-MMU HARTs as invalid in generic platform fw_platform_init(). Signed-off-by: Anup Patel <anup.patel@wdc.com> Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-09-16lib: sbi: Ensure coldboot HART supports next privilege modeAnup Patel1-1/+28
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>
2020-09-16lib: utils: Improve fdt_cpu_fixup() implementationAnup Patel1-2/+11
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>
2020-09-16lib: sbi: Allow specifying mode in sbi_hart_pmp_check_addr() APIAnup Patel5-20/+33
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>
2020-09-16lib: sbi: Allow specifying start mode to sbi_hsm_hart_start() APIAnup Patel3-3/+11
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>
2020-09-09lib: sbi_trap: Allow M-mode to M-mode ECALLsAnup Patel1-0/+1
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>
2020-09-09include: Rename ECALL defines to match latest RISC-V specAnup Patel3-4/+4
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>
2020-09-09lib: sbi: Don't handle VS-mode ecall in sbi_trap_handler()Anup Patel1-1/+0
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>
2020-09-01lib: sbi: Improve HPM CSR read/write emulationAnup Patel1-72/+75
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>
2020-09-01include: sbi: Few cosmetic changes in riscv_encoding.hAnup Patel1-87/+139
This patch does following cosmentic changes to riscv_encoding.h: 1. Re-organize CSR defines to match CSR listing in latest RISC-V privilege spec 2. Rename CSR_HCOUNTERNEN to CSR_HCOUNTEREN Signed-off-by: Anup Patel <anup.patel@wdc.com> Reviewed-by: Atish Patra <atish.patra@wdc.com>
2020-09-01lib: sbi: Detect and print MHPM counters at boot-timeAnup Patel3-0/+19
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>
2020-09-01lib: sbi: Improve PMP CSR detection and progammingAnup Patel3-145/+180
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>
2020-09-01lib: sbi: Remove redundant SBI_HART_HAS_PMP featureAnup Patel3-20/+5
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>
2020-08-21lib: sbi: Handle the case where MTVAL has illegal instruction addressAnup Patel1-6/+15
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>
2020-08-21lib: sbi_init: Avoid thundering hurd problem with coldboot_lockAnup Patel1-7/+13
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>