Commit Graph

5 Commits

Author SHA1 Message Date
Peter Yuen
975fcf1355 arch-riscv: Fixed CPU switching and PLIC issue with MinorCPU
Added takeover methods for PMA Checker and RiscvTLB to ensure
that checkpoint restoration works. Also added logic in PLIC
to prevent posting interrupts to a CPU that has yet to complete
the current interrupt. PLIC's behaviour when a CPU claims another
interrupt before completion is also changed. Now PLIC will return
the uncompleted interrupt ID instead of return 0. This behaviour
is not documented in the specs but is designed this way to avoid
issues from CPU side (especially MinorCPU).

Change-Id: I68eaaf56d2c4d76cc1e0a1e2160f5abe184c2cd5
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/41933
Maintainer: Bobby R. Bruce <bbruce@ucdavis.edu>
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Ayaz Akram <yazakram@ucdavis.edu>
2021-03-13 08:06:29 +00:00
Bobby R. Bruce
bd6e1fc9c5 arch-riscv,misc: Add missing overrides for clang compilation
The Clang compiler returns "missing override" errors without these.

Change-Id: I62af6c338b000123c924f0b3205551579bd5aeb4
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/41913
Reviewed-by: Gabe Black <gabe.black@gmail.com>
Reviewed-by: Hoa Nguyen <hoanguyen@ucdavis.edu>
Maintainer: Bobby R. Bruce <bbruce@ucdavis.edu>
Tested-by: kokoro <noreply+kokoro@google.com>
2021-02-26 18:59:30 +00:00
Peter
69eb60d87e arch-riscv: RISC-V HiFive Platform implementation
This patch implements the RISC-V HiFive Platform
(based on the SiFive HiFive series). The HiFive
platform requires a PLIC and CLINT device (based on
current HiFive boards).

The optional uart_int_id field redirects Console interrupts
to the PLIC interrupt controller.

PlicDevice is a wrapper around BasicPioDevice that
requires an interrupt ID. Interrupts are expected to
be raised via platform->postPciInterrupt(id).

VirtIOMMIO is a slight modification from the ARM
implementation such that interrupts are posted through
PLIC

PlicDevice is a wrapper around BasicPioDevice that
requires an interrupt ID. Interrupts are expected to
be raised via platform->postPciInterrupt(id).

VirtIOMMIO is a slight modification from the ARM
implementation such that interrupts are posted through
PLIC.

Uart8250 was modified slightly for easier Python
setup.

Change-Id: I4bbdb5f903b52a41d1b7e0ccc44877c46cd30d56
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/40599
Reviewed-by: Ayaz Akram <yazakram@ucdavis.edu>
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
2021-02-23 03:43:47 +00:00
Peter
de06ab35ef arch-riscv: PLIC Implementation
This patch contains the implementation for the RISC-V PLIC.
The PLIC Memory Map is based on the SiFive U54MC datasheet.
The PLIC models a 3-cycle latency as stated in the RISC-V
specs.

Change-Id: I571c7bd3bd2918c92e4f207a1b57cf9d06e9c72f
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/40598
Reviewed-by: Ayaz Akram <yazakram@ucdavis.edu>
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
2021-02-23 03:43:47 +00:00
Peter
4cca1d89e8 arch-riscv: Implementation of CLINT
This patch implements the CLINT device model based
on the SiFive U54MC datasheet. CLINT is modelled to
receive its clock signal via an interrupt pin. A
generic RTC (non-MMIO) is also implemented to provide
this signal at arbitrary frequencies.

isa.cc is also modified to provide a correct implementation
of the rdtime instruction. It will read from the miscreg
file (which is updated by CLINT every time mtime is
incremented).

Change-Id: I6f5393f3a8fdbd059f25df51d3d74bcb28da09f1
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/40597
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Ayaz Akram <yazakram@ucdavis.edu>
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
2021-02-23 03:43:47 +00:00