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Commit Graph

5 Commits

Author SHA1 Message Date
Palmer Dabbelt
57e5c814e9
cache: StarFive: Require a 64-bit system
This has a bunch of {read,write}q() calls, so it won't work on 32-bit
systems.  I don't think there's any 32-bit StarFive systems, so for now
just require 64-bit.

Fixes: cabff60ca7 ("cache: Add StarFive StarLink cache management")
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Emil Renner Berthing <emil.renner.berthing@canonical.com>
Link: https://lore.kernel.org/r/20240722154519.25375-2-palmer@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-08-01 07:15:02 -07:00
Joshua Yeong
cabff60ca7 cache: Add StarFive StarLink cache management
Add StarFive Starlink cache management driver.
The driver enables RISC-V non-standard cache
operation on SoC that does not support Zicbom
extension instructions.

Signed-off-by: Joshua Yeong <joshua.yeong@starfivetech.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
2024-05-28 12:34:11 +01:00
Conor Dooley
971f128bb2 soc: sifive: shunt ccache driver to drivers/cache
Move the ccache driver over to drivers/cache, out of the drivers/soc
dumping ground, to this new collection point for cache controller
drivers.

Reviewed-by: Samuel Holland <samuel.holland@sifive.com>
Tested-by: Samuel Holland <samuel.holland@sifive.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
2023-11-22 11:49:25 +00:00
Christoph Hellwig
fd96278127 riscv: RISCV_NONSTANDARD_CACHE_OPS shouldn't depend on RISCV_DMA_NONCOHERENT
RISCV_NONSTANDARD_CACHE_OPS is also used for the pmem cache maintenance
helpers, which are built into the kernel unconditionally.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20231018052654.50074-2-hch@lst.de
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
2023-10-26 09:42:37 +02:00
Lad Prabhakar
d34599bcd2
cache: Add L2 cache management for Andes AX45MP RISC-V core
I/O Coherence Port (IOCP) provides an AXI interface for connecting
external non-caching masters, such as DMA controllers. The accesses
from IOCP are coherent with D-Caches and L2 Cache.

IOCP is a specification option and is disabled on the Renesas RZ/Five
SoC due to this reason IP blocks using DMA will fail.

The Andes AX45MP core has a Programmable Physical Memory Attributes (PMA)
block that allows dynamic adjustment of memory attributes in the runtime.
It contains a configurable amount of PMA entries implemented as CSR
registers to control the attributes of memory locations in interest.
Below are the memory attributes supported:
* Device, Non-bufferable
* Device, bufferable
* Memory, Non-cacheable, Non-bufferable
* Memory, Non-cacheable, Bufferable
* Memory, Write-back, No-allocate
* Memory, Write-back, Read-allocate
* Memory, Write-back, Write-allocate
* Memory, Write-back, Read and Write-allocate

More info about PMA (section 10.3):
Link: http://www.andestech.com/wp-content/uploads/AX45MP-1C-Rev.-5.0.0-Datasheet.pdf

As a workaround for SoCs with IOCP disabled CMO needs to be handled by
software. Firstly OpenSBI configures the memory region as
"Memory, Non-cacheable, Bufferable" and passes this region as a global
shared dma pool as a DT node. With DMA_GLOBAL_POOL enabled all DMA
allocations happen from this region and synchronization callbacks are
implemented to synchronize when doing DMA transactions.

Example PMA region passes as a DT node from OpenSBI:
    reserved-memory {
        #address-cells = <2>;
        #size-cells = <2>;
        ranges;

        pma_resv0@58000000 {
            compatible = "shared-dma-pool";
            reg = <0x0 0x58000000 0x0 0x08000000>;
            no-map;
            linux,dma-default;
        };
    };

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Tested-by: Conor Dooley <conor.dooley@microchip.com> # tyre-kicking on a d1
Link: https://lore.kernel.org/r/20230818135723.80612-6-prabhakar.mahadev-lad.rj@bp.renesas.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-09-01 09:08:59 -07:00