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