1 /*
2 * Copyright (C) 2004 Florian Schirmer <jolt@tuxbox.org>
3 * Copyright (C) 2007 Aurelien Jarno <aurelien@aurel32.net>
4 * Copyright (C) 2010-2012 Hauke Mehrtens <hauke@hauke-m.de>
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License as published by the
8 * Free Software Foundation; either version 2 of the License, or (at your
9 * option) any later version.
10 *
11 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
12 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
13 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
14 * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
15 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
16 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
17 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
18 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
19 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
20 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
21 *
22 * You should have received a copy of the GNU General Public License along
23 * with this program; if not, write to the Free Software Foundation, Inc.,
24 * 675 Mass Ave, Cambridge, MA 02139, USA.
25 */
26
27 #include <linux/init.h>
28 #include <linux/types.h>
29 #include <linux/kernel.h>
30 #include <linux/memblock.h>
31 #include <linux/spinlock.h>
32 #include <linux/ssb/ssb_driver_chipcommon.h>
33 #include <linux/ssb/ssb_regs.h>
34 #include <linux/smp.h>
35 #include <asm/bmips.h>
36 #include <asm/bootinfo.h>
37 #include <bcm47xx.h>
38 #include <bcm47xx_board.h>
39 #include "bcm47xx_private.h"
40
41 static char bcm47xx_system_type[20] = "Broadcom BCM47XX";
42
43 const char *get_system_type(void)
44 {
45 return bcm47xx_system_type;
46 }
47
48 __init void bcm47xx_set_system_type(u16 chip_id)
49 {
50 snprintf(bcm47xx_system_type, sizeof(bcm47xx_system_type),
51 (chip_id > 0x9999) ? "Broadcom BCM%d" :
52 "Broadcom BCM%04X",
53 chip_id);
54 }
55
56 static unsigned long lowmem __initdata;
57
58 static __init void prom_init_mem(void)
59 {
60 unsigned long mem;
61 unsigned long max;
62 unsigned long off;
63 struct cpuinfo_mips *c = ¤t_cpu_data;
64
65 /* Figure out memory size by finding aliases.
66 *
67 * We should theoretically use the mapping from CFE using cfe_enummem().
68 * However as the BCM47XX is mostly used on low-memory systems, we
69 * want to reuse the memory used by CFE (around 4MB). That means cfe_*
70 * functions stop to work at some point during the boot, we should only
71 * call them at the beginning of the boot.
72 *
73 * BCM47XX uses 128MB for addressing the ram, if the system contains
74 * less than that amount of ram it remaps the ram more often into the
75 * available space.
76 */
77
78 /* Physical address, without mapping to any kernel segment */
79 off = CPHYSADDR((unsigned long)prom_init);
80
81 /* Accessing memory after 128 MiB will cause an exception */
82 max = 128 << 20;
83
84 for (mem = 1 << 20; mem < max; mem += 1 << 20) {
85 /* Loop condition may be not enough, off may be over 1 MiB */
86 if (off + mem >= max) {
87 mem = max;
88 pr_debug("Assume 128MB RAM\n");
89 break;
90 }
91 if (!memcmp((void *)prom_init, (void *)prom_init + mem, 32))
92 break;
93 }
94 lowmem = mem;
95
96 /* Ignoring the last page when ddr size is 128M. Cached
97 * accesses to last page is causing the processor to prefetch
98 * using address above 128M stepping out of the ddr address
99 * space.
100 */
101 if (c->cputype == CPU_74K && (mem == (128 << 20)))
102 mem -= 0x1000;
103 memblock_add(0, mem);
104 }
105
106 /*
107 * This is the first serial on the chip common core, it is at this position
108 * for sb (ssb) and ai (bcma) bus.
109 */
110 #define BCM47XX_SERIAL_ADDR (SSB_ENUM_BASE + SSB_CHIPCO_UART0_DATA)
111
112 void __init prom_init(void)
113 {
114 /* Cache CBR addr before CPU/DMA setup */
115 bmips_cbr_addr = BMIPS_GET_CBR();
116 prom_init_mem();
117 setup_8250_early_printk_port(CKSEG1ADDR(BCM47XX_SERIAL_ADDR), 0, 0);
118 }
119
120 #if defined(CONFIG_BCM47XX_BCMA) && defined(CONFIG_HIGHMEM)
121
122 #define EXTVBASE 0xc0000000
123 #define ENTRYLO(x) ((pte_val(pfn_pte((x) >> PFN_PTE_SHIFT, PAGE_KERNEL_UNCACHED)) >> 6) | 1)
124
125 #include <asm/tlbflush.h>
126
127 /* Stripped version of tlb_init, with the call to build_tlb_refill_handler
128 * dropped. Calling it at this stage causes a hang.
129 */
130 static void early_tlb_init(void)
131 {
132 write_c0_pagemask(PM_DEFAULT_MASK);
133 write_c0_wired(0);
134 temp_tlb_entry = current_cpu_data.tlbsize - 1;
135 local_flush_tlb_all();
136 }
137
138 void __init bcm47xx_prom_highmem_init(void)
139 {
140 unsigned long off = (unsigned long)prom_init;
141 unsigned long extmem = 0;
142 bool highmem_region = false;
143
144 if (WARN_ON(bcm47xx_bus_type != BCM47XX_BUS_TYPE_BCMA))
145 return;
146
147 if (bcm47xx_bus.bcma.bus.chipinfo.id == BCMA_CHIP_ID_BCM4706)
148 highmem_region = true;
149
150 if (lowmem != 128 << 20 || !highmem_region)
151 return;
152
153 early_tlb_init();
154
155 /* Add one temporary TLB entry to map SDRAM Region 2.
156 * Physical Virtual
157 * 0x80000000 0xc0000000 (1st: 256MB)
158 * 0x90000000 0xd0000000 (2nd: 256MB)
159 */
160 add_temporary_entry(ENTRYLO(0x80000000),
161 ENTRYLO(0x80000000 + (256 << 20)),
162 EXTVBASE, PM_256M);
163
164 off = EXTVBASE + __pa(off);
165 for (extmem = 128 << 20; extmem < 512 << 20; extmem <<= 1) {
166 if (!memcmp((void *)prom_init, (void *)(off + extmem), 16))
167 break;
168 }
169 extmem -= lowmem;
170
171 early_tlb_init();
172
173 if (!extmem)
174 return;
175
176 pr_warn("Found %lu MiB of extra memory, but highmem is unsupported yet!\n",
177 extmem >> 20);
178
179 /* TODO: Register extra memory */
180 }
181
182 #endif /* defined(CONFIG_BCM47XX_BCMA) && defined(CONFIG_HIGHMEM) */
183
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.