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Diffstat (limited to 'arch/mips/bcm47xx/prom.c')
| -rw-r--r-- | arch/mips/bcm47xx/prom.c | 178 |
1 files changed, 178 insertions, 0 deletions
diff --git a/arch/mips/bcm47xx/prom.c b/arch/mips/bcm47xx/prom.c new file mode 100644 index 0000000000..99a1ba5394 --- /dev/null +++ b/arch/mips/bcm47xx/prom.c @@ -0,0 +1,178 @@ +/* + * Copyright (C) 2004 Florian Schirmer <jolt@tuxbox.org> + * Copyright (C) 2007 Aurelien Jarno <aurelien@aurel32.net> + * Copyright (C) 2010-2012 Hauke Mehrtens <hauke@hauke-m.de> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + * + * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED + * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN + * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF + * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON + * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 675 Mass Ave, Cambridge, MA 02139, USA. + */ + +#include <linux/init.h> +#include <linux/types.h> +#include <linux/kernel.h> +#include <linux/memblock.h> +#include <linux/spinlock.h> +#include <linux/ssb/ssb_driver_chipcommon.h> +#include <linux/ssb/ssb_regs.h> +#include <linux/smp.h> +#include <asm/bootinfo.h> +#include <bcm47xx.h> +#include <bcm47xx_board.h> + +static char bcm47xx_system_type[20] = "Broadcom BCM47XX"; + +const char *get_system_type(void) +{ + return bcm47xx_system_type; +} + +__init void bcm47xx_set_system_type(u16 chip_id) +{ + snprintf(bcm47xx_system_type, sizeof(bcm47xx_system_type), + (chip_id > 0x9999) ? "Broadcom BCM%d" : + "Broadcom BCM%04X", + chip_id); +} + +static unsigned long lowmem __initdata; + +static __init void prom_init_mem(void) +{ + unsigned long mem; + unsigned long max; + unsigned long off; + struct cpuinfo_mips *c = ¤t_cpu_data; + + /* Figure out memory size by finding aliases. + * + * We should theoretically use the mapping from CFE using cfe_enummem(). + * However as the BCM47XX is mostly used on low-memory systems, we + * want to reuse the memory used by CFE (around 4MB). That means cfe_* + * functions stop to work at some point during the boot, we should only + * call them at the beginning of the boot. + * + * BCM47XX uses 128MB for addressing the ram, if the system contains + * less than that amount of ram it remaps the ram more often into the + * available space. + */ + + /* Physical address, without mapping to any kernel segment */ + off = CPHYSADDR((unsigned long)prom_init); + + /* Accessing memory after 128 MiB will cause an exception */ + max = 128 << 20; + + for (mem = 1 << 20; mem < max; mem += 1 << 20) { + /* Loop condition may be not enough, off may be over 1 MiB */ + if (off + mem >= max) { + mem = max; + pr_debug("Assume 128MB RAM\n"); + break; + } + if (!memcmp((void *)prom_init, (void *)prom_init + mem, 32)) + break; + } + lowmem = mem; + + /* Ignoring the last page when ddr size is 128M. Cached + * accesses to last page is causing the processor to prefetch + * using address above 128M stepping out of the ddr address + * space. + */ + if (c->cputype == CPU_74K && (mem == (128 << 20))) + mem -= 0x1000; + memblock_add(0, mem); +} + +/* + * This is the first serial on the chip common core, it is at this position + * for sb (ssb) and ai (bcma) bus. + */ +#define BCM47XX_SERIAL_ADDR (SSB_ENUM_BASE + SSB_CHIPCO_UART0_DATA) + +void __init prom_init(void) +{ + prom_init_mem(); + setup_8250_early_printk_port(CKSEG1ADDR(BCM47XX_SERIAL_ADDR), 0, 0); +} + +#if defined(CONFIG_BCM47XX_BCMA) && defined(CONFIG_HIGHMEM) + +#define EXTVBASE 0xc0000000 +#define ENTRYLO(x) ((pte_val(pfn_pte((x) >> PFN_PTE_SHIFT, PAGE_KERNEL_UNCACHED)) >> 6) | 1) + +#include <asm/tlbflush.h> + +/* Stripped version of tlb_init, with the call to build_tlb_refill_handler + * dropped. Calling it at this stage causes a hang. + */ +void early_tlb_init(void) +{ + write_c0_pagemask(PM_DEFAULT_MASK); + write_c0_wired(0); + temp_tlb_entry = current_cpu_data.tlbsize - 1; + local_flush_tlb_all(); +} + +void __init bcm47xx_prom_highmem_init(void) +{ + unsigned long off = (unsigned long)prom_init; + unsigned long extmem = 0; + bool highmem_region = false; + + if (WARN_ON(bcm47xx_bus_type != BCM47XX_BUS_TYPE_BCMA)) + return; + + if (bcm47xx_bus.bcma.bus.chipinfo.id == BCMA_CHIP_ID_BCM4706) + highmem_region = true; + + if (lowmem != 128 << 20 || !highmem_region) + return; + + early_tlb_init(); + + /* Add one temporary TLB entry to map SDRAM Region 2. + * Physical Virtual + * 0x80000000 0xc0000000 (1st: 256MB) + * 0x90000000 0xd0000000 (2nd: 256MB) + */ + add_temporary_entry(ENTRYLO(0x80000000), + ENTRYLO(0x80000000 + (256 << 20)), + EXTVBASE, PM_256M); + + off = EXTVBASE + __pa(off); + for (extmem = 128 << 20; extmem < 512 << 20; extmem <<= 1) { + if (!memcmp((void *)prom_init, (void *)(off + extmem), 16)) + break; + } + extmem -= lowmem; + + early_tlb_init(); + + if (!extmem) + return; + + pr_warn("Found %lu MiB of extra memory, but highmem is unsupported yet!\n", + extmem >> 20); + + /* TODO: Register extra memory */ +} + +#endif /* defined(CONFIG_BCM47XX_BCMA) && defined(CONFIG_HIGHMEM) */ |