diff --git a/sys/riscv/sifive/sifive_ccache.c b/sys/riscv/sifive/sifive_ccache.c new file mode 100644 --- /dev/null +++ b/sys/riscv/sifive/sifive_ccache.c @@ -0,0 +1,177 @@ +/*- + * SPDX-License-Identifier: BSD-2-Clause + * + * Copyright (c) 2024 Ruslan Bukin + * + * This software was developed by the University of Cambridge Computer + * Laboratory (Department of Computer Science and Technology) under Innovate + * UK project 105694, "Digital Security by Design (DSbD) Technology Platform + * Prototype". + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include + +#include +#include +#include + +#define SIFIVE_CCACHE_CONFIG 0x000 +#define CCACHE_CONFIG_WAYS_S 8 +#define CCACHE_CONFIG_WAYS_M (0xff << CCACHE_CONFIG_WAYS_S) +#define SIFIVE_CCACHE_WAYENABLE 0x008 +#define SIFIVE_CCACHE_FLUSH64 0x200 + +#define SIFIVE_CCACHE_LINE_SIZE 64 + +#define RD8(sc, off) (bus_read_8((sc)->res, (off))) +#define WR8(sc, off, val) (bus_write_8((sc)->res, (off), (val))) +#define CC_WR8(offset, value) \ + *(volatile uint64_t *)((uintptr_t)ccache_va + (offset)) = (value) + +static struct ofw_compat_data compat_data[] = { + { "sifive,eic7700", 1 }, + { NULL, 0 } +}; + +struct ccache_softc { + struct resource *res; +}; + +static void *ccache_va = NULL; + +static struct resource_spec ccache_spec[] = { + { SYS_RES_MEMORY, 0, RF_ACTIVE }, + { -1, 0 } +}; + +/* + * Non-standard EIC7700 cache-flushing routine. + */ +static void +ccache_flush_range(vm_offset_t start, size_t len) +{ + vm_offset_t paddr; + vm_offset_t sva; + vm_offset_t step; + uint64_t line; + + if (ccache_va == NULL || len == 0) + return; + + mb(); + + for (sva = start; len > 0;) { + paddr = pmap_kextract(sva); + step = min(PAGE_SIZE - (paddr & PAGE_MASK), len); + for (line = rounddown2(paddr, SIFIVE_CCACHE_LINE_SIZE); + line < paddr + step; + line += SIFIVE_CCACHE_LINE_SIZE) + CC_WR8(SIFIVE_CCACHE_FLUSH64, line); + sva += step; + len -= step; + } + + mb(); +} + +static void +ccache_install_hooks(void) +{ + struct riscv_cache_ops eswin_ops; + + eswin_ops.dcache_wbinv_range = ccache_flush_range; + eswin_ops.dcache_inv_range = ccache_flush_range; + eswin_ops.dcache_wb_range = ccache_flush_range; + + riscv_cache_install_hooks(&eswin_ops, SIFIVE_CCACHE_LINE_SIZE); +} + +static int +ccache_probe(device_t dev) +{ + + if (!ofw_bus_status_okay(dev)) + return (ENXIO); + + if (ofw_bus_search_compatible(dev, compat_data)->ocd_data == 0) + return (ENXIO); + + if (device_get_unit(dev) != 0) + return (ENXIO); + + device_set_desc(dev, "SiFive Cache Controller"); + + return (BUS_PROBE_DEFAULT); +} + +static int +ccache_attach(device_t dev) +{ + struct ccache_softc *sc; + size_t config, ways; + + sc = device_get_softc(dev); + + if (bus_alloc_resources(dev, ccache_spec, &sc->res) != 0) { + device_printf(dev, "cannot allocate resources for device\n"); + return (ENXIO); + } + + /* Non-standard EIC7700 cache unit configuration. */ + config = RD8(sc, SIFIVE_CCACHE_CONFIG); + ways = (config & CCACHE_CONFIG_WAYS_M) >> CCACHE_CONFIG_WAYS_S; + WR8(sc, SIFIVE_CCACHE_WAYENABLE, (ways - 1)); + + ccache_va = rman_get_virtual(sc->res); + ccache_install_hooks(); + + return (0); +} + +static device_method_t ccache_methods[] = { + /* Device interface */ + DEVMETHOD(device_probe, ccache_probe), + DEVMETHOD(device_attach, ccache_attach), + DEVMETHOD_END +}; + +static driver_t ccache_driver = { + "ccache", + ccache_methods, + sizeof(struct ccache_softc), +}; + +EARLY_DRIVER_MODULE(ccache, simplebus, ccache_driver, 0, 0, + BUS_PASS_BUS + BUS_PASS_ORDER_FIRST); +MODULE_VERSION(ccache, 1);