xref: /openbsd-src/sys/dev/fdt/amlsm.c (revision 99fd087599a8791921855f21bd7e36130f39aadc)
1 /*	$OpenBSD: amlsm.c,v 1.1 2020/01/14 20:43:20 kettenis Exp $	*/
2 /*
3  * Copyright (c) 2020 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 #include <sys/timeout.h>
22 
23 #include <machine/bus.h>
24 #include <machine/fdt.h>
25 
26 #include <dev/ofw/openfirm.h>
27 #include <dev/ofw/fdt.h>
28 #include <dev/ofw/ofw_misc.h>
29 #include <dev/rndvar.h>
30 
31 extern register_t smc_call(register_t, register_t, register_t, register_t);
32 
33 /* Calls */
34 #define AML_SM_GET_SHARE_MEM_INPUT_BASE		0x82000020
35 #define AML_SM_GET_SHARE_MEM_OUTPUT_BASE	0x82000021
36 #define AML_SM_EFUSE_READ			0x82000030
37 #define AML_SM_EFUSE_USER_MAX			0x82000033
38 #define AML_SM_JTAG_ON				0x82000040
39 #define AML_SM_JTAG_OFF				0x82000041
40 #define AML_SM_GET_CHIP_ID			0x82000044
41 
42 struct aml_cpu_info {
43 	uint32_t	version;
44 	uint32_t	chip_id[4];
45 };
46 
47 struct amlsm_softc {
48 	struct device		sc_dev;
49 	bus_space_tag_t		sc_iot;
50 	bus_space_handle_t	sc_in_ioh;
51 	bus_space_handle_t	sc_out_ioh;
52 };
53 
54 int	amlsm_match(struct device *, void *, void *);
55 void	amlsm_attach(struct device *, struct device *, void *);
56 
57 struct cfattach	amlsm_ca = {
58 	sizeof (struct amlsm_softc), amlsm_match, amlsm_attach
59 };
60 
61 struct cfdriver amlsm_cd = {
62 	NULL, "amlsm", DV_DULL
63 };
64 
65 int
66 amlsm_match(struct device *parent, void *match, void *aux)
67 {
68 	struct fdt_attach_args *faa = aux;
69 
70 	return OF_is_compatible(faa->fa_node, "amlogic,meson-gxbb-sm");
71 }
72 
73 void
74 amlsm_attach(struct device *parent, struct device *self, void *aux)
75 {
76 	struct amlsm_softc *sc = (struct amlsm_softc *)self;
77 	struct fdt_attach_args *faa = aux;
78 	struct aml_cpu_info *info;
79 	bus_addr_t addr;
80 	int32_t ret;
81 	int i;
82 
83 	sc->sc_iot = faa->fa_iot;
84 
85 	addr = smc_call(AML_SM_GET_SHARE_MEM_INPUT_BASE, 0, 0, 0);
86 	if (addr == (bus_addr_t)-1 ||
87 	    bus_space_map(sc->sc_iot, addr, PAGE_SIZE,
88 	    BUS_SPACE_MAP_CACHEABLE, &sc->sc_in_ioh)) {
89 		printf(": can't map shared memory\n");
90 		return;
91 	}
92 	addr = smc_call(AML_SM_GET_SHARE_MEM_OUTPUT_BASE, 0, 0, 0);
93 	if (addr == (bus_addr_t)-1 ||
94 	    bus_space_map(sc->sc_iot, addr, PAGE_SIZE,
95 	    BUS_SPACE_MAP_CACHEABLE, &sc->sc_out_ioh)) {
96 		bus_space_unmap(sc->sc_iot, sc->sc_in_ioh, PAGE_SIZE);
97 		printf(": can't map shared memory\n");
98 		return;
99 	}
100 
101 	/*
102 	 * Version 2 gives us a 16-byte chip ID.  If that fails, fall
103 	 * back on version 0/1 which gives us a 12-byte chipt ID.
104 	 */
105 	info = bus_space_vaddr(sc->sc_iot, sc->sc_out_ioh);
106 	memset(info, 0, sizeof(struct aml_cpu_info));
107 	ret = smc_call(AML_SM_GET_CHIP_ID, 2, 0, 0);
108 	if (ret == -1)
109 		ret = smc_call(AML_SM_GET_CHIP_ID, 0, 0, 0);
110 
111 	printf(": ver %u\n", info->version);
112 
113 	if (ret != -1) {
114 		for (i = 0; i < nitems(info->chip_id); i++)
115 			enqueue_randomness(info->chip_id[i]);
116 	}
117 }
118