arch/mips/mach-pic32/cpu.c

   1 /*
   2  * Copyright (C) 2015
   3  * Purna Chandra Mandal <purna.mandal@microchip.com>
   4  *
   5  * SPDX-License-Identifier:     GPL-2.0+
   6  *
   7  */
   8 #include <common.h>
   9 #include <clk.h>
  10 #include <dm.h>
  11 #include <mach/pic32.h>
  12 #include <mach/ddr.h>
  13 #include <dt-bindings/clock/microchip,clock.h>
  14
  15 /* Flash prefetch */
  16 #define PRECON          0x00
  17
  18 /* Flash ECCCON */
  19 #define ECC_MASK        0x03
  20 #define ECC_SHIFT       4
  21
  22 #define CLK_MHZ(x)      ((x) / 1000000)
  23
  24 DECLARE_GLOBAL_DATA_PTR;
  25
  26 static ulong rate(int id)
  27 {
  28         int ret;
  29         struct udevice *dev;
  30         struct clk clk;
  31         ulong rate;
  32
  33         ret = uclass_get_device(UCLASS_CLK, 0, &dev);
  34         if (ret) {
  35                 printf("clk-uclass not found\n");
  36                 return 0;
  37         }
  38
  39         clk.id = id;
  40         ret = clk_request(dev, &clk);
  41         if (ret < 0)
  42                 return ret;
  43
  44         rate = clk_get_rate(&clk);
  45
  46         clk_free(&clk);
  47
  48         return rate;
  49 }
  50
  51 static ulong clk_get_cpu_rate(void)
  52 {
  53         return rate(PB7CLK);
  54 }
  55
  56 /* initialize prefetch module related to cpu_clk */
  57 static void prefetch_init(void)
  58 {
  59         struct pic32_reg_atomic *regs;
  60         const void __iomem *base;
  61         int v, nr_waits;
  62         ulong rate;
  63
  64         /* cpu frequency in MHZ */
  65         rate = clk_get_cpu_rate() / 1000000;
  66
  67         /* get flash ECC type */
  68         base = pic32_get_syscfg_base();
  69         v = (readl(base + CFGCON) >> ECC_SHIFT) & ECC_MASK;
  70
  71         if (v < 2) {
  72                 if (rate < 66)
  73                         nr_waits = 0;
  74                 else if (rate < 133)
  75                         nr_waits = 1;
  76                 else
  77                         nr_waits = 2;
  78         } else {
  79                 if (rate <= 83)
  80                         nr_waits = 0;
  81                 else if (rate <= 166)
  82                         nr_waits = 1;
  83                 else
  84                         nr_waits = 2;
  85         }
  86
  87         regs = ioremap(PREFETCH_BASE + PRECON, sizeof(*regs));
  88         writel(nr_waits, &regs->raw);
  89
  90         /* Enable prefetch for all */
  91         writel(0x30, &regs->set);
  92         iounmap(regs);
  93 }
  94
  95 /* arch specific CPU init after DM */
  96 int arch_cpu_init_dm(void)
  97 {
  98         /* flash prefetch */
  99         prefetch_init();
 100         return 0;
 101 }
 102
 103 /* Un-gate DDR2 modules (gated by default) */
 104 static void ddr2_pmd_ungate(void)
 105 {
 106         void __iomem *regs;
 107
 108         regs = pic32_get_syscfg_base();
 109         writel(0, regs + PMD7);
 110 }
 111
 112 /* initialize the DDR2 Controller and DDR2 PHY */
 113 phys_size_t initdram(void)
 114 {
 115         ddr2_pmd_ungate();
 116         ddr2_phy_init();
 117         ddr2_ctrl_init();
 118         return ddr2_calculate_size();
 119 }
 120
 121 int misc_init_r(void)
 122 {
 123         set_io_port_base(0);
 124         return 0;
 125 }
 126
 127 #ifdef CONFIG_DISPLAY_BOARDINFO
 128 const char *get_core_name(void)
 129 {
 130         u32 proc_id;
 131         const char *str;
 132
 133         proc_id = read_c0_prid();
 134         switch (proc_id) {
 135         case 0x19e28:
 136                 str = "PIC32MZ[DA]";
 137                 break;
 138         default:
 139                 str = "UNKNOWN";
 140         }
 141
 142         return str;
 143 }
 144 #endif
 145 #ifdef CONFIG_CMD_CLK
 146
 147 int soc_clk_dump(void)
 148 {
 149         int i;
 150
 151         printf("PLL Speed: %lu MHz\n",
 152                CLK_MHZ(rate(PLLCLK)));
 153
 154         printf("CPU Speed: %lu MHz\n", CLK_MHZ(rate(PB7CLK)));
 155
 156         printf("MPLL Speed: %lu MHz\n", CLK_MHZ(rate(MPLL)));
 157
 158         for (i = PB1CLK; i <= PB7CLK; i++)
 159                 printf("PB%d Clock Speed: %lu MHz\n", i - PB1CLK + 1,
 160                        CLK_MHZ(rate(i)));
 161
 162         for (i = REF1CLK; i <= REF5CLK; i++)
 163                 printf("REFO%d Clock Speed: %lu MHz\n", i - REF1CLK + 1,
 164                        CLK_MHZ(rate(i)));
 165         return 0;
 166 }
 167 #endif