Linux 3.17-rc2
[linux/fpc-iii.git] / arch / mips / bcm47xx / prom.c
blob1b170bf5f7f0bbb57bf47b204c1e6ac9fc9af7d2
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>
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.
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.
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.
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>
39 static char bcm47xx_system_type[20] = "Broadcom BCM47XX";
41 const char *get_system_type(void)
43 return bcm47xx_system_type;
46 __init void bcm47xx_set_system_type(u16 chip_id)
48 snprintf(bcm47xx_system_type, sizeof(bcm47xx_system_type),
49 (chip_id > 0x9999) ? "Broadcom BCM%d" :
50 "Broadcom BCM%04X",
51 chip_id);
54 static unsigned long lowmem __initdata;
56 static __init void prom_init_mem(void)
58 unsigned long mem;
59 unsigned long max;
60 unsigned long off;
61 struct cpuinfo_mips *c = &current_cpu_data;
63 /* Figure out memory size by finding aliases.
65 * We should theoretically use the mapping from CFE using cfe_enummem().
66 * However as the BCM47XX is mostly used on low-memory systems, we
67 * want to reuse the memory used by CFE (around 4MB). That means cfe_*
68 * functions stop to work at some point during the boot, we should only
69 * call them at the beginning of the boot.
71 * BCM47XX uses 128MB for addressing the ram, if the system contains
72 * less that that amount of ram it remaps the ram more often into the
73 * available space.
76 /* Physical address, without mapping to any kernel segment */
77 off = CPHYSADDR((unsigned long)prom_init);
79 /* Accessing memory after 128 MiB will cause an exception */
80 max = 128 << 20;
82 for (mem = 1 << 20; mem < max; mem += 1 << 20) {
83 /* Loop condition may be not enough, off may be over 1 MiB */
84 if (off + mem >= max) {
85 mem = max;
86 printk(KERN_DEBUG "assume 128MB RAM\n");
87 break;
89 if (!memcmp(prom_init, prom_init + mem, 32))
90 break;
92 lowmem = mem;
94 /* Ignoring the last page when ddr size is 128M. Cached
95 * accesses to last page is causing the processor to prefetch
96 * using address above 128M stepping out of the ddr address
97 * space.
99 if (c->cputype == CPU_74K && (mem == (128 << 20)))
100 mem -= 0x1000;
101 add_memory_region(0, mem, BOOT_MEM_RAM);
105 * This is the first serial on the chip common core, it is at this position
106 * for sb (ssb) and ai (bcma) bus.
108 #define BCM47XX_SERIAL_ADDR (SSB_ENUM_BASE + SSB_CHIPCO_UART0_DATA)
110 void __init prom_init(void)
112 prom_init_mem();
113 setup_8250_early_printk_port(CKSEG1ADDR(BCM47XX_SERIAL_ADDR), 0, 0);
116 void __init prom_free_prom_memory(void)
120 #if defined(CONFIG_BCM47XX_BCMA) && defined(CONFIG_HIGHMEM)
122 #define EXTVBASE 0xc0000000
123 #define ENTRYLO(x) ((pte_val(pfn_pte((x) >> _PFN_SHIFT, PAGE_KERNEL_UNCACHED)) >> 6) | 1)
125 #include <asm/tlbflush.h>
127 /* Stripped version of tlb_init, with the call to build_tlb_refill_handler
128 * dropped. Calling it at this stage causes a hang.
130 void __cpuinit early_tlb_init(void)
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();
138 void __init bcm47xx_prom_highmem_init(void)
140 unsigned long off = (unsigned long)prom_init;
141 unsigned long extmem = 0;
142 bool highmem_region = false;
144 if (WARN_ON(bcm47xx_bus_type != BCM47XX_BUS_TYPE_BCMA))
145 return;
147 if (bcm47xx_bus.bcma.bus.chipinfo.id == BCMA_CHIP_ID_BCM4706)
148 highmem_region = true;
150 if (lowmem != 128 << 20 || !highmem_region)
151 return;
153 early_tlb_init();
155 /* Add one temporary TLB entry to map SDRAM Region 2.
156 * Physical Virtual
157 * 0x80000000 0xc0000000 (1st: 256MB)
158 * 0x90000000 0xd0000000 (2nd: 256MB)
160 add_temporary_entry(ENTRYLO(0x80000000),
161 ENTRYLO(0x80000000 + (256 << 20)),
162 EXTVBASE, PM_256M);
164 off = EXTVBASE + __pa(off);
165 for (extmem = 128 << 20; extmem < 512 << 20; extmem <<= 1) {
166 if (!memcmp(prom_init, (void *)(off + extmem), 16))
167 break;
169 extmem -= lowmem;
171 early_tlb_init();
173 if (!extmem)
174 return;
176 pr_warn("Found %lu MiB of extra memory, but highmem is unsupported yet!\n",
177 extmem >> 20);
179 /* TODO: Register extra memory */
182 #endif /* defined(CONFIG_BCM47XX_BCMA) && defined(CONFIG_HIGHMEM) */