1 /* $OpenBSD: sfcc.c,v 1.4 2022/12/27 21:13:25 kettenis Exp $ */
2 /*
3 * Copyright (c) 2021 Mark Kettenis <kettenis@openbsd.org>
4 *
5 * Permission to use, copy, modify, and distribute this software for any
6 * purpose with or without fee is hereby granted, provided that the above
7 * copyright notice and this permission notice appear in all copies.
8 *
9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16 */
17
18 #include <sys/param.h>
19 #include <sys/systm.h>
20 #include <sys/device.h>
21
22 #include <machine/bus.h>
23 #include <machine/cpufunc.h>
24 #include <machine/fdt.h>
25
26 #include <dev/ofw/openfirm.h>
27 #include <dev/ofw/fdt.h>
28
29 /* Registers. */
30 #define SFCC_FLUSH64 0x200
31
32 struct sfcc_softc {
33 struct device sc_dev;
34 bus_space_tag_t sc_iot;
35 bus_space_handle_t sc_ioh;
36
37 uint32_t sc_line_size;
38 };
39
40 struct sfcc_softc *sfcc_sc;
41
42 int sfcc_match(struct device *, void *, void *);
43 void sfcc_attach(struct device *, struct device *, void *);
44
45 const struct cfattach sfcc_ca = {
46 sizeof (struct sfcc_softc), sfcc_match, sfcc_attach
47 };
48
49 struct cfdriver sfcc_cd = {
50 NULL, "sfcc", DV_DULL
51 };
52
53 void sfcc_cache_wbinv_range(paddr_t, psize_t);
54
55 int
sfcc_match(struct device * parent,void * match,void * aux)56 sfcc_match(struct device *parent, void *match, void *aux)
57 {
58 struct fdt_attach_args *faa = aux;
59
60 return (OF_is_compatible(faa->fa_node, "sifive,fu540-c000-ccache") ||
61 OF_is_compatible(faa->fa_node, "starfive,jh7100-ccache"));
62 }
63
64 void
sfcc_attach(struct device * parent,struct device * self,void * aux)65 sfcc_attach(struct device *parent, struct device *self, void *aux)
66 {
67 struct sfcc_softc *sc = (struct sfcc_softc *)self;
68 struct fdt_attach_args *faa = aux;
69
70 if (faa->fa_nreg < 1) {
71 printf(": no registers\n");
72 return;
73 }
74
75 sc->sc_iot = faa->fa_iot;
76 if (bus_space_map(sc->sc_iot, faa->fa_reg[0].addr,
77 faa->fa_reg[0].size, 0, &sc->sc_ioh)) {
78 printf(": can't map registers\n");
79 return;
80 }
81
82 printf("\n");
83
84 sc->sc_line_size = OF_getpropint(faa->fa_node, "cache-block-size", 64);
85 sfcc_sc = sc;
86
87 /*
88 * Cache lines can only be flushed, so we use the same
89 * operation everywhere.
90 */
91 cpu_dcache_wbinv_range = sfcc_cache_wbinv_range;
92 cpu_dcache_inv_range = sfcc_cache_wbinv_range;
93 cpu_dcache_wb_range = sfcc_cache_wbinv_range;
94 }
95
96 void
sfcc_cache_wbinv_range(paddr_t pa,psize_t len)97 sfcc_cache_wbinv_range(paddr_t pa, psize_t len)
98 {
99 struct sfcc_softc *sc = sfcc_sc;
100 paddr_t end, mask;
101
102 mask = sc->sc_line_size - 1;
103 end = (pa + len + mask) & ~mask;
104 pa &= ~mask;
105
106 __asm volatile ("fence iorw,iorw" ::: "memory");
107 while (pa != end) {
108 bus_space_write_8(sc->sc_iot, sc->sc_ioh, SFCC_FLUSH64, pa);
109 __asm volatile ("fence iorw,iorw" ::: "memory");
110 pa += sc->sc_line_size;
111 }
112 }
113