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/spinlock.h>
31 #include <linux/ssb/ssb_driver_chipcommon.h>
32 #include <linux/ssb/ssb_regs.h>
33 #include <linux/smp.h>
34 #include <asm/bootinfo.h>
35 #include <bcm47xx.h>
36 #include <bcm47xx_board.h>
37
38 static char bcm47xx_system_type[20] = "Broadcom BCM47XX";
39
40 const char *get_system_type(void)
41 {
42 return bcm47xx_system_type;
43 }
44
45 __init void bcm47xx_set_system_type(u16 chip_id)
46 {
47 snprintf(bcm47xx_system_type, sizeof(bcm47xx_system_type),
48 (chip_id > 0x9999) ? "Broadcom BCM%d" :
49 "Broadcom BCM%04X",
50 chip_id);
51 }
52
53 static unsigned long lowmem __initdata;
54
55 static __init void prom_init_mem(void)
56 {
57 unsigned long mem;
58 unsigned long max;
59 unsigned long off;
60 struct cpuinfo_mips *c = ¤t_cpu_data;
61
62 /* Figure out memory size by finding aliases.
63 *
64 * We should theoretically use the mapping from CFE using cfe_enummem().
65 * However as the BCM47XX is mostly used on low-memory systems, we
66 * want to reuse the memory used by CFE (around 4MB). That means cfe_*
67 * functions stop to work at some point during the boot, we should only
68 * call them at the beginning of the boot.
69 *
70 * BCM47XX uses 128MB for addressing the ram, if the system contains
71 * less that that amount of ram it remaps the ram more often into the
72 * available space.
73 */
74
75 /* Physical address, without mapping to any kernel segment */
76 off = CPHYSADDR((unsigned long)prom_init);
77
78 /* Accessing memory after 128 MiB will cause an exception */
79 max = 128 << 20;
80
81 for (mem = 1 << 20; mem < max; mem += 1 << 20) {
82 /* Loop condition may be not enough, off may be over 1 MiB */
83 if (off + mem >= max) {
84 mem = max;
85 pr_debug("Assume 128MB RAM\n");
86 break;
87 }
88 if (!memcmp(prom_init, prom_init + mem, 32))
89 break;
90 }
91 lowmem = mem;
92
93 /* Ignoring the last page when ddr size is 128M. Cached
94 * accesses to last page is causing the processor to prefetch
95 * using address above 128M stepping out of the ddr address
96 * space.
97 */
98 if (c->cputype == CPU_74K && (mem == (128 << 20)))
99 mem -= 0x1000;
100 add_memory_region(0, mem, BOOT_MEM_RAM);
101 }
102
103 /*
104 * This is the first serial on the chip common core, it is at this position
105 * for sb (ssb) and ai (bcma) bus.
106 */
107 #define BCM47XX_SERIAL_ADDR (SSB_ENUM_BASE + SSB_CHIPCO_UART0_DATA)
108
109 void __init prom_init(void)
110 {
111 prom_init_mem();
112 setup_8250_early_printk_port(CKSEG1ADDR(BCM47XX_SERIAL_ADDR), 0, 0);
113 }
114
115 void __init prom_free_prom_memory(void)
116 {
117 }
118
119 #if defined(CONFIG_BCM47XX_BCMA) && defined(CONFIG_HIGHMEM)
120
121 #define EXTVBASE 0xc0000000
122 #define ENTRYLO(x) ((pte_val(pfn_pte((x) >> _PFN_SHIFT, PAGE_KERNEL_UNCACHED)) >> 6) | 1)
123
124 #include <asm/tlbflush.h>
125
126 /* Stripped version of tlb_init, with the call to build_tlb_refill_handler
127 * dropped. Calling it at this stage causes a hang.
128 */
129 void early_tlb_init(void)
130 {
131 write_c0_pagemask(PM_DEFAULT_MASK);
132 write_c0_wired(0);
133 temp_tlb_entry = current_cpu_data.tlbsize - 1;
134 local_flush_tlb_all();
135 }
136
137 void __init bcm47xx_prom_highmem_init(void)
138 {
139 unsigned long off = (unsigned long)prom_init;
140 unsigned long extmem = 0;
141 bool highmem_region = false;
142
143 if (WARN_ON(bcm47xx_bus_type != BCM47XX_BUS_TYPE_BCMA))
144 return;
145
146 if (bcm47xx_bus.bcma.bus.chipinfo.id == BCMA_CHIP_ID_BCM4706)
147 highmem_region = true;
148
149 if (lowmem != 128 << 20 || !highmem_region)
150 return;
151
152 early_tlb_init();
153
154 /* Add one temporary TLB entry to map SDRAM Region 2.
155 * Physical Virtual
156 * 0x80000000 0xc0000000 (1st: 256MB)
157 * 0x90000000 0xd0000000 (2nd: 256MB)
158 */
159 add_temporary_entry(ENTRYLO(0x80000000),
160 ENTRYLO(0x80000000 + (256 << 20)),
161 EXTVBASE, PM_256M);
162
163 off = EXTVBASE + __pa(off);
164 for (extmem = 128 << 20; extmem < 512 << 20; extmem <<= 1) {
165 if (!memcmp(prom_init, (void *)(off + extmem), 16))
166 break;
167 }
168 extmem -= lowmem;
169
170 early_tlb_init();
171
172 if (!extmem)
173 return;
174
175 pr_warn("Found %lu MiB of extra memory, but highmem is unsupported yet!\n",
176 extmem >> 20);
177
178 /* TODO: Register extra memory */
179 }
180
181 #endif /* defined(CONFIG_BCM47XX_BCMA) && defined(CONFIG_HIGHMEM) */