/*
   * This file is subject to the terms and conditions of the GNU General Public
   * License.  See the file "COPYING" in the main directory of this archive
   * for more details.
   *
   * Copyright (C) 2008 Maxime Bizon <mbizon@freebox.fr>
   * Copyright (C) 2009 Florian Fainelli <florian@openwrt.org>
   */
  
  #include <linux/kernel.h>
  #include <linux/module.h>
  #include <linux/cpu.h>

  #include <asm/cpu.h>

  #include <asm/cpu-info.h>

  #include <asm/mipsregs.h>

  #include <bcm63xx_cpu.h>
  #include <bcm63xx_regs.h>
  #include <bcm63xx_io.h>
  #include <bcm63xx_irq.h>
  
  const unsigned long *bcm63xx_regs_base;
  EXPORT_SYMBOL(bcm63xx_regs_base);
  
  const int *bcm63xx_irqs;
  EXPORT_SYMBOL(bcm63xx_irqs);
  
  static u16 bcm63xx_cpu_id;
  static u16 bcm63xx_cpu_rev;
  static unsigned int bcm63xx_cpu_freq;
  static unsigned int bcm63xx_memory_size;

  static const unsigned long bcm6338_regs_base[] = {
  	__GEN_CPU_REGS_TABLE(6338)

  };

  static const int bcm6338_irqs[] = {
  	__GEN_CPU_IRQ_TABLE(6338)

  };

  static const unsigned long bcm6345_regs_base[] = {
  	__GEN_CPU_REGS_TABLE(6345)

  };

  static const int bcm6345_irqs[] = {
  	__GEN_CPU_IRQ_TABLE(6345)

  };

  static const unsigned long bcm6348_regs_base[] = {
  	__GEN_CPU_REGS_TABLE(6348)

  };

  static const int bcm6348_irqs[] = {
  	__GEN_CPU_IRQ_TABLE(6348)

  };

  static const unsigned long bcm6358_regs_base[] = {
  	__GEN_CPU_REGS_TABLE(6358)

  };

  static const int bcm6358_irqs[] = {
  	__GEN_CPU_IRQ_TABLE(6358)

  };

  static const unsigned long bcm6368_regs_base[] = {
  	__GEN_CPU_REGS_TABLE(6368)
  };
  
  static const int bcm6368_irqs[] = {
  	__GEN_CPU_IRQ_TABLE(6368)
  
  };

  u16 __bcm63xx_get_cpu_id(void)
  {
  	return bcm63xx_cpu_id;
  }
  
  EXPORT_SYMBOL(__bcm63xx_get_cpu_id);
  
  u16 bcm63xx_get_cpu_rev(void)
  {
  	return bcm63xx_cpu_rev;
  }
  
  EXPORT_SYMBOL(bcm63xx_get_cpu_rev);
  
  unsigned int bcm63xx_get_cpu_freq(void)
  {
  	return bcm63xx_cpu_freq;
  }
  
  unsigned int bcm63xx_get_memory_size(void)
  {
  	return bcm63xx_memory_size;
  }
  
  static unsigned int detect_cpu_clock(void)
  {

  	switch (bcm63xx_get_cpu_id()) {
  	case BCM6338_CPU_ID:
  		/* BCM6338 has a fixed 240 Mhz frequency */

  		return 240000000;

  	case BCM6345_CPU_ID:
  		/* BCM6345 has a fixed 140Mhz frequency */

  		return 140000000;

  	case BCM6348_CPU_ID:
  	{
  		unsigned int tmp, n1, n2, m1;

  		/* 16MHz * (N1 + 1) * (N2 + 2) / (M1_CPU + 1) */
  		tmp = bcm_perf_readl(PERF_MIPSPLLCTL_REG);
  		n1 = (tmp & MIPSPLLCTL_N1_MASK) >> MIPSPLLCTL_N1_SHIFT;
  		n2 = (tmp & MIPSPLLCTL_N2_MASK) >> MIPSPLLCTL_N2_SHIFT;
  		m1 = (tmp & MIPSPLLCTL_M1CPU_MASK) >> MIPSPLLCTL_M1CPU_SHIFT;
  		n1 += 1;
  		n2 += 2;
  		m1 += 1;

  		return (16 * 1000000 * n1 * n2) / m1;

  	}

  	case BCM6358_CPU_ID:
  	{
  		unsigned int tmp, n1, n2, m1;

  		/* 16MHz * N1 * N2 / M1_CPU */
  		tmp = bcm_ddr_readl(DDR_DMIPSPLLCFG_REG);
  		n1 = (tmp & DMIPSPLLCFG_N1_MASK) >> DMIPSPLLCFG_N1_SHIFT;
  		n2 = (tmp & DMIPSPLLCFG_N2_MASK) >> DMIPSPLLCFG_N2_SHIFT;
  		m1 = (tmp & DMIPSPLLCFG_M1_MASK) >> DMIPSPLLCFG_M1_SHIFT;

  		return (16 * 1000000 * n1 * n2) / m1;

  	}

  	case BCM6368_CPU_ID:
  	{
  		unsigned int tmp, p1, p2, ndiv, m1;
  
  		/* (64MHz / P1) * P2 * NDIV / M1_CPU */
  		tmp = bcm_ddr_readl(DDR_DMIPSPLLCFG_6368_REG);
  
  		p1 = (tmp & DMIPSPLLCFG_6368_P1_MASK) >>
  			DMIPSPLLCFG_6368_P1_SHIFT;
  
  		p2 = (tmp & DMIPSPLLCFG_6368_P2_MASK) >>
  			DMIPSPLLCFG_6368_P2_SHIFT;
  
  		ndiv = (tmp & DMIPSPLLCFG_6368_NDIV_MASK) >>
  			DMIPSPLLCFG_6368_NDIV_SHIFT;
  
  		tmp = bcm_ddr_readl(DDR_DMIPSPLLDIV_6368_REG);
  		m1 = (tmp & DMIPSPLLDIV_6368_MDIV_MASK) >>
  			DMIPSPLLDIV_6368_MDIV_SHIFT;
  
  		return (((64 * 1000000) / p1) * p2 * ndiv) / m1;
  	}
  
  	default:
  		BUG();
  	}

  }
  
  /*
   * attempt to detect the amount of memory installed
   */
  static unsigned int detect_memory_size(void)
  {
  	unsigned int cols = 0, rows = 0, is_32bits = 0, banks = 0;
  	u32 val;

  	if (BCMCPU_IS_6345()) {
  		val = bcm_sdram_readl(SDRAM_MBASE_REG);
  		return (val * 8 * 1024 * 1024);
  	}

  
  	if (BCMCPU_IS_6338() || BCMCPU_IS_6348()) {
  		val = bcm_sdram_readl(SDRAM_CFG_REG);
  		rows = (val & SDRAM_CFG_ROW_MASK) >> SDRAM_CFG_ROW_SHIFT;
  		cols = (val & SDRAM_CFG_COL_MASK) >> SDRAM_CFG_COL_SHIFT;
  		is_32bits = (val & SDRAM_CFG_32B_MASK) ? 1 : 0;
  		banks = (val & SDRAM_CFG_BANK_MASK) ? 2 : 1;
  	}

  	if (BCMCPU_IS_6358() || BCMCPU_IS_6368()) {

  		val = bcm_memc_readl(MEMC_CFG_REG);
  		rows = (val & MEMC_CFG_ROW_MASK) >> MEMC_CFG_ROW_SHIFT;
  		cols = (val & MEMC_CFG_COL_MASK) >> MEMC_CFG_COL_SHIFT;
  		is_32bits = (val & MEMC_CFG_32B_MASK) ? 0 : 1;
  		banks = 2;
  	}
  
  	/* 0 => 11 address bits ... 2 => 13 address bits */
  	rows += 11;
  
  	/* 0 => 8 address bits ... 2 => 10 address bits */
  	cols += 8;
  
  	return 1 << (cols + rows + (is_32bits + 1) + banks);
  }
  
  void __init bcm63xx_cpu_init(void)
  {
  	unsigned int tmp, expected_cpu_id;
  	struct cpuinfo_mips *c = &current_cpu_data;

  	unsigned int cpu = smp_processor_id();

  
  	/* soc registers location depends on cpu type */
  	expected_cpu_id = 0;
  
  	switch (c->cputype) {

  	case CPU_BMIPS3300:
  		if ((read_c0_prid() & 0xff00) == PRID_IMP_BMIPS3300_ALT) {
  			expected_cpu_id = BCM6348_CPU_ID;

  			bcm63xx_regs_base = bcm6348_regs_base;
  			bcm63xx_irqs = bcm6348_irqs;

  		} else {
  			__cpu_name[cpu] = "Broadcom BCM6338";
  			expected_cpu_id = BCM6338_CPU_ID;

  			bcm63xx_regs_base = bcm6338_regs_base;
  			bcm63xx_irqs = bcm6338_irqs;

  		}

  		break;

  	case CPU_BMIPS32:

  		expected_cpu_id = BCM6345_CPU_ID;

  		bcm63xx_regs_base = bcm6345_regs_base;
  		bcm63xx_irqs = bcm6345_irqs;

  		break;

  	case CPU_BMIPS4350:

  		switch (read_c0_prid() & 0xf0) {
  		case 0x10:
  			expected_cpu_id = BCM6358_CPU_ID;
  			bcm63xx_regs_base = bcm6358_regs_base;
  			bcm63xx_irqs = bcm6358_irqs;
  			break;
  		case 0x30:
  			expected_cpu_id = BCM6368_CPU_ID;
  			bcm63xx_regs_base = bcm6368_regs_base;
  			bcm63xx_irqs = bcm6368_irqs;
  			break;
  		}

  		break;
  	}
  
  	/*
  	 * really early to panic, but delaying panic would not help since we
  	 * will never get any working console
  	 */
  	if (!expected_cpu_id)
  		panic("unsupported Broadcom CPU");
  
  	/*
  	 * bcm63xx_regs_base is set, we can access soc registers
  	 */
  
  	/* double check CPU type */
  	tmp = bcm_perf_readl(PERF_REV_REG);
  	bcm63xx_cpu_id = (tmp & REV_CHIPID_MASK) >> REV_CHIPID_SHIFT;
  	bcm63xx_cpu_rev = (tmp & REV_REVID_MASK) >> REV_REVID_SHIFT;
  
  	if (bcm63xx_cpu_id != expected_cpu_id)
  		panic("bcm63xx CPU id mismatch");
  
  	bcm63xx_cpu_freq = detect_cpu_clock();
  	bcm63xx_memory_size = detect_memory_size();
  
  	printk(KERN_INFO "Detected Broadcom 0x%04x CPU revision %02x
  ",
  	       bcm63xx_cpu_id, bcm63xx_cpu_rev);
  	printk(KERN_INFO "CPU frequency is %u MHz
  ",
  	       bcm63xx_cpu_freq / 1000000);
  	printk(KERN_INFO "%uMB of RAM installed
  ",
  	       bcm63xx_memory_size >> 20);
  }