2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
4 * Copyright (c) 2019 Kyle Evans <kevans@FreeBSD.org>
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 #include <sys/cdefs.h>
31 __FBSDID("$FreeBSD$");
34 * This file contains facilities for runtime determination of address space
35 * mappings for use in DMA/mailbox interactions. This is only used for the
36 * arm64 SoC because the 32-bit SoC used the same mappings.
38 #if defined (__aarch64__)
42 #include <sys/types.h>
43 #include <sys/systm.h>
45 #include <dev/ofw/openfirm.h>
46 #include <dev/ofw/ofw_bus.h>
47 #include <dev/ofw/ofw_bus_subr.h>
49 #include <machine/bus.h>
51 #include <arm/broadcom/bcm2835/bcm2835_vcbus.h>
54 * This structure describes mappings that need to take place when transforming
55 * ARM core addresses into vcbus addresses for use with the DMA/mailbox
56 * interfaces. Currently, we only deal with peripheral/SDRAM address spaces
59 * The SDRAM address space is consistently mapped starting at 0 and extends to
60 * the size of the installed SDRAM.
62 * Peripherals are mapped further up at spots that vary per-SOC.
64 struct bcm283x_memory_mapping {
65 vm_paddr_t armc_start;
67 vm_paddr_t vcbus_start;
70 #if defined(SOC_BCM2835) || defined(SOC_BCM2836)
71 static struct bcm283x_memory_mapping bcm2835_memmap[] = {
74 .armc_start = 0x00000000,
75 .armc_size = BCM2835_ARM_IO_BASE,
76 .vcbus_start = BCM2835_VCBUS_SDRAM_BASE,
80 .armc_start = BCM2835_ARM_IO_BASE,
81 .armc_size = BCM28XX_ARM_IO_SIZE,
82 .vcbus_start = BCM2835_VCBUS_IO_BASE,
88 #ifdef SOC_BRCM_BCM2837
89 static struct bcm283x_memory_mapping bcm2837_memmap[] = {
92 .armc_start = 0x00000000,
93 .armc_size = BCM2837_ARM_IO_BASE,
94 .vcbus_start = BCM2837_VCBUS_SDRAM_BASE,
98 .armc_start = BCM2837_ARM_IO_BASE,
99 .armc_size = BCM28XX_ARM_IO_SIZE,
100 .vcbus_start = BCM2837_VCBUS_IO_BASE,
106 #ifdef SOC_BRCM_BCM2838
109 * The BCM2838 supports up to 4GB of SDRAM, but unfortunately we can still only
110 * map the first 1GB into the "legacy master view" (vcbus) address space. Thus,
111 * peripherals can still only access the lower end of SDRAM. For this reason,
112 * we also capture the main-peripheral busdma restriction below.
114 static struct bcm283x_memory_mapping bcm2838_memmap[] = {
117 .armc_start = 0x00000000,
118 .armc_size = 0x40000000,
119 .vcbus_start = BCM2838_VCBUS_SDRAM_BASE,
122 /* Main peripherals */
123 .armc_start = BCM2838_ARM_IO_BASE,
124 .armc_size = BCM28XX_ARM_IO_SIZE,
125 .vcbus_start = BCM2838_VCBUS_IO_BASE,
131 static struct bcm283x_memory_soc_cfg {
132 struct bcm283x_memory_mapping *memmap;
133 const char *soc_compat;
134 bus_addr_t busdma_lowaddr;
135 } bcm283x_memory_configs[] = {
138 .memmap = bcm2835_memmap,
139 .soc_compat = "brcm,bcm2835",
140 .busdma_lowaddr = BUS_SPACE_MAXADDR_32BIT,
145 .memmap = bcm2835_memmap,
146 .soc_compat = "brcm,bcm2836",
147 .busdma_lowaddr = BUS_SPACE_MAXADDR_32BIT,
151 #ifdef SOC_BRCM_BCM2837
153 .memmap = bcm2837_memmap,
154 .soc_compat = "brcm,bcm2837",
155 .busdma_lowaddr = BUS_SPACE_MAXADDR_32BIT,
158 #ifdef SOC_BRCM_BCM2838
160 .memmap = bcm2838_memmap,
161 .soc_compat = "brcm,bcm2838",
162 .busdma_lowaddr = BCM2838_PERIPH_MAXADDR,
167 static struct bcm283x_memory_soc_cfg *booted_soc_memcfg;
169 static struct bcm283x_memory_soc_cfg *
170 bcm283x_get_current_memcfg(void)
175 /* We'll cache it once we decide, because it won't change per-boot. */
176 if (booted_soc_memcfg != NULL)
177 return (booted_soc_memcfg);
179 KASSERT(nitems(bcm283x_memory_configs) != 0,
180 ("No SOC memory configurations enabled!"));
182 root = OF_finddevice("/");
183 for (i = 0; i < nitems(bcm283x_memory_configs); ++i) {
184 booted_soc_memcfg = &bcm283x_memory_configs[i];
185 printf("Checking root against %s\n",
186 booted_soc_memcfg->soc_compat);
187 if (ofw_bus_node_is_compatible(root,
188 booted_soc_memcfg->soc_compat))
189 return (booted_soc_memcfg);
193 * The kernel doesn't fit the board; we can't really make a reasonable
194 * guess, as these SOC are different enough that something will blow up
197 panic("No suitable SOC memory configuration found.");
200 #define BCM283X_MEMMAP_ISTERM(ent) \
201 ((ent)->armc_start == 0 && (ent)->armc_size == 0 && \
202 (ent)->vcbus_start == 0)
205 bcm283x_armc_to_vcbus(vm_paddr_t pa)
207 struct bcm283x_memory_soc_cfg *cfg;
208 struct bcm283x_memory_mapping *map, *ment;
210 /* Guaranteed not NULL if we haven't panicked yet. */
211 cfg = bcm283x_get_current_memcfg();
213 for (ment = map; !BCM283X_MEMMAP_ISTERM(ment); ++ment) {
214 if (pa >= ment->armc_start &&
215 pa < ment->armc_start + ment->armc_size) {
216 return (pa - ment->armc_start) + ment->vcbus_start;
221 * Assume 1:1 mapping for anything else, but complain about it on
225 printf("bcm283x_vcbus: No armc -> vcbus mapping found: %jx\n",
231 bcm283x_vcbus_to_armc(vm_paddr_t vca)
233 struct bcm283x_memory_soc_cfg *cfg;
234 struct bcm283x_memory_mapping *map, *ment;
236 /* Guaranteed not NULL if we haven't panicked yet. */
237 cfg = bcm283x_get_current_memcfg();
239 for (ment = map; !BCM283X_MEMMAP_ISTERM(ment); ++ment) {
240 if (vca >= ment->vcbus_start &&
241 vca < ment->vcbus_start + ment->armc_size) {
242 return (vca - ment->vcbus_start) + ment->armc_start;
247 * Assume 1:1 mapping for anything else, but complain about it on
251 printf("bcm283x_vcbus: No vcbus -> armc mapping found: %jx\n",
257 bcm283x_dmabus_peripheral_lowaddr(void)
259 struct bcm283x_memory_soc_cfg *cfg;
261 cfg = bcm283x_get_current_memcfg();
262 return (cfg->busdma_lowaddr);