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/smp.h> 32 #include <asm/bootinfo.h> 33 #include <asm/fw/cfe/cfe_api.h> 34 #include <asm/fw/cfe/cfe_error.h> 35 36 static int cfe_cons_handle; 37 38 const char *get_system_type(void) 39 { 40 return "Broadcom BCM47XX"; 41 } 42 43 void prom_putchar(char c) 44 { 45 while (cfe_write(cfe_cons_handle, &c, 1) == 0) 46 ; 47 } 48 49 static __init void prom_init_cfe(void) 50 { 51 uint32_t cfe_ept; 52 uint32_t cfe_handle; 53 uint32_t cfe_eptseal; 54 int argc = fw_arg0; 55 char **envp = (char **) fw_arg2; 56 int *prom_vec = (int *) fw_arg3; 57 58 /* 59 * Check if a loader was used; if NOT, the 4 arguments are 60 * what CFE gives us (handle, 0, EPT and EPTSEAL) 61 */ 62 if (argc < 0) { 63 cfe_handle = (uint32_t)argc; 64 cfe_ept = (uint32_t)envp; 65 cfe_eptseal = (uint32_t)prom_vec; 66 } else { 67 if ((int)prom_vec < 0) { 68 /* 69 * Old loader; all it gives us is the handle, 70 * so use the "known" entrypoint and assume 71 * the seal. 72 */ 73 cfe_handle = (uint32_t)prom_vec; 74 cfe_ept = 0xBFC00500; 75 cfe_eptseal = CFE_EPTSEAL; 76 } else { 77 /* 78 * Newer loaders bundle the handle/ept/eptseal 79 * Note: prom_vec is in the loader's useg 80 * which is still alive in the TLB. 81 */ 82 cfe_handle = prom_vec[0]; 83 cfe_ept = prom_vec[2]; 84 cfe_eptseal = prom_vec[3]; 85 } 86 } 87 88 if (cfe_eptseal != CFE_EPTSEAL) { 89 /* too early for panic to do any good */ 90 printk(KERN_ERR "CFE's entrypoint seal doesn't match."); 91 while (1) ; 92 } 93 94 cfe_init(cfe_handle, cfe_ept); 95 } 96 97 static __init void prom_init_console(void) 98 { 99 /* Initialize CFE console */ 100 cfe_cons_handle = cfe_getstdhandle(CFE_STDHANDLE_CONSOLE); 101 } 102 103 static __init void prom_init_cmdline(void) 104 { 105 static char buf[COMMAND_LINE_SIZE] __initdata; 106 107 /* Get the kernel command line from CFE */ 108 if (cfe_getenv("LINUX_CMDLINE", buf, COMMAND_LINE_SIZE) >= 0) { 109 buf[COMMAND_LINE_SIZE - 1] = 0; 110 strcpy(arcs_cmdline, buf); 111 } 112 113 /* Force a console handover by adding a console= argument if needed, 114 * as CFE is not available anymore later in the boot process. */ 115 if ((strstr(arcs_cmdline, "console=")) == NULL) { 116 /* Try to read the default serial port used by CFE */ 117 if ((cfe_getenv("BOOT_CONSOLE", buf, COMMAND_LINE_SIZE) < 0) 118 || (strncmp("uart", buf, 4))) 119 /* Default to uart0 */ 120 strcpy(buf, "uart0"); 121 122 /* Compute the new command line */ 123 snprintf(arcs_cmdline, COMMAND_LINE_SIZE, "%s console=ttyS%c,115200", 124 arcs_cmdline, buf[4]); 125 } 126 } 127 128 static __init void prom_init_mem(void) 129 { 130 unsigned long mem; 131 unsigned long max; 132 unsigned long off; 133 struct cpuinfo_mips *c = ¤t_cpu_data; 134 135 /* Figure out memory size by finding aliases. 136 * 137 * We should theoretically use the mapping from CFE using cfe_enummem(). 138 * However as the BCM47XX is mostly used on low-memory systems, we 139 * want to reuse the memory used by CFE (around 4MB). That means cfe_* 140 * functions stop to work at some point during the boot, we should only 141 * call them at the beginning of the boot. 142 * 143 * BCM47XX uses 128MB for addressing the ram, if the system contains 144 * less that that amount of ram it remaps the ram more often into the 145 * available space. 146 * Accessing memory after 128MB will cause an exception. 147 * max contains the biggest possible address supported by the platform. 148 * If the method wants to try something above we assume 128MB ram. 149 */ 150 off = (unsigned long)prom_init; 151 max = off | ((128 << 20) - 1); 152 for (mem = (1 << 20); mem < (128 << 20); mem += (1 << 20)) { 153 if ((off + mem) > max) { 154 mem = (128 << 20); 155 printk(KERN_DEBUG "assume 128MB RAM\n"); 156 break; 157 } 158 if (!memcmp(prom_init, prom_init + mem, 32)) 159 break; 160 } 161 162 /* Ignoring the last page when ddr size is 128M. Cached 163 * accesses to last page is causing the processor to prefetch 164 * using address above 128M stepping out of the ddr address 165 * space. 166 */ 167 if (c->cputype == CPU_74K && (mem == (128 << 20))) 168 mem -= 0x1000; 169 170 add_memory_region(0, mem, BOOT_MEM_RAM); 171 } 172 173 void __init prom_init(void) 174 { 175 prom_init_cfe(); 176 prom_init_console(); 177 prom_init_cmdline(); 178 prom_init_mem(); 179 } 180 181 void __init prom_free_prom_memory(void) 182 { 183 } 184