opensbi.git/lib/sbi/sbi_timer.c, branch v1.4

lib: sbi: Add Zicntr as a HART ISA extension

2023-07-09T05:36:24Z

Recently ratified Zicntr ISA extension covers cycle, time and instret CSRs so we replace the "time" ISA extension with "zicntr" ISA extension in OpenSBI. Signed-off-by: Anup Patel Reviewed-by: Xiang W

lib: sbi_timer: Added a conditional wait function which can timeout

2022-07-08T09:21:24Z

Motivation: Suppose a peripheral needs to be configured to transmit data. There is an SFR bit which indicates that the peripheral is ready to transmit. The firmware should check the bit and will only transmit data when the peripheral is ready. When the firmware starts polling the SFR, the peripheral could be busy transmitting/receiving other data so the firmware must wait till that completes. Assuming that there is no other way, the firmware shouldn't wait indefinitely. The function sbi_timer_waitms_until() will constantly check whether a certain condition is satisfied, or timeout occurs. It can be used for the cases when a timeout is required. Signed-off-by: Adnan Rahman Chowdhury Reviewed-by: Xiang W Reviewed-by: Anup Patel

lib: sbi_timer: Drop unnecessary get_platform_ticks wrapper

2022-05-30T05:13:03Z

The device's timer_value callback is already the right prototype to use for the get_time_val function pointer. Signed-off-by: Samuel Holland Reviewed-by: Anup Patel

lib: sbi: Convert hart features into hart extensions

2022-05-07T04:46:30Z

Since past few years, we have been using "hart features" in OpenSBI to represent all optionalities and multi-letter extensions defined by the RISC-V specifications. The RISC-V profiles specification has taken a different approach and started assigning extension names for all optionalities which did not have any extension name previously. (Refer, https://github.com/riscv/riscv-profiles/blob/main/profiles.adoc) Inspired from the RISC-V profiles specification, we convert OpenSBI hart features into hart extensions. Going forward, we align the extension naming with RISC-V profiles specification. Currently, only "time CSR" and "AIA CSR" have not been assigned extension name but for everything else we have a name. Signed-off-by: Anup Patel Reviewed-by: Atish Patra

lib: sbi: Implement Sstc extension

2022-04-28T06:15:21Z

Recently, Sstc extension was ratified. It defines stimecmp which allows the supervisor mode to directly update the timecmp value without the need of the SBI call. The hardware also can inject the S-mode timer interrupt direclty to the supervisor without going through the M-mode. To maintain backward compatibility with the older software, SBI call now uses stimecmp directly if the hardware supports. Implement the Sstc extension. Signed-off-by: Atish Patra Reviewed-by: Anup Patel

lib: sbi: Add generic timer delay loop function

2021-09-26T14:22:15Z

We now have frequency of the timer device provided by the platform support so we can emulate desired delay using a loop where the number loop iterations are based on timer frequency. This patch provides sbi_timer_delay_loop() for above purpose. Signed-off-by: Anup Patel Reviewed-by: Bin Meng Reviewed-by: Xiang W

lib: sbi: Implement firmware counters

2021-07-11T05:08:23Z

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 Signed-off-by: Atish Patra

lib: sbi_scratch: remove owner from sbi_scratch_alloc_offset

2021-06-02T11:37:26Z

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 Reviewed-by: Xiang W Reviewed-by: Anup Patel

lib: sbi: Simplify timer platform operations

2021-04-28T11:30:49Z

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 Reviewed-by: Alistair Francis

include: sbi: Use scratch pointer as parmeter in HART feature APIs

2020-05-19T03:49:42Z

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 Reviewed-by: Atish Patra