arch/arm/cpu/armv7/bcm281xx/clk-eth.c

   1 /*
   2  * Copyright 2014 Broadcom Corporation.
   3  *
   4  * SPDX-License-Identifier:     GPL-2.0+
   5  */
   6
   7 #include <common.h>
   8 #include <asm/io.h>
   9 #include <linux/errno.h>
  10 #include <asm/arch/sysmap.h>
  11 #include <asm/kona-common/clk.h>
  12 #include "clk-core.h"
  13
  14 #define WR_ACCESS_ADDR                  ESUB_CLK_BASE_ADDR
  15 #define WR_ACCESS_PASSWORD                              0xA5A500
  16
  17 #define PLLE_POST_RESETB_ADDR           (ESUB_CLK_BASE_ADDR + 0x00000C00)
  18
  19 #define PLLE_RESETB_ADDR                (ESUB_CLK_BASE_ADDR + 0x00000C58)
  20 #define PLLE_RESETB_I_PLL_RESETB_PLLE_MASK              0x00010000
  21 #define PLLE_POST_RESETB_I_POST_RESETB_PLLE_MASK        0x00000001
  22
  23 #define PLL_LOCK_ADDR                   (ESUB_CLK_BASE_ADDR + 0x00000C38)
  24 #define PLL_LOCK_PLL_LOCK_PLLE_MASK                     0x00000001
  25
  26 #define ESW_SYS_DIV_ADDR                (ESUB_CLK_BASE_ADDR + 0x00000A04)
  27 #define ESW_SYS_DIV_PLL_SELECT_MASK                     0x00000300
  28 #define ESW_SYS_DIV_DIV_MASK                            0x0000001C
  29 #define ESW_SYS_DIV_PLL_VAR_208M_CLK_SELECT             0x00000100
  30 #define ESW_SYS_DIV_DIV_SELECT                          0x4
  31 #define ESW_SYS_DIV_TRIGGER_MASK                        0x00000001
  32
  33 #define ESUB_AXI_DIV_DEBUG_ADDR         (ESUB_CLK_BASE_ADDR + 0x00000E04)
  34 #define ESUB_AXI_DIV_DEBUG_PLL_SELECT_MASK              0x0000001C
  35 #define ESUB_AXI_DIV_DEBUG_PLL_SELECT_OVERRIDE_MASK     0x00000040
  36 #define ESUB_AXI_DIV_DEBUG_PLL_VAR_208M_CLK_SELECT      0x0
  37 #define ESUB_AXI_DIV_DEBUG_TRIGGER_MASK                 0x00000001
  38
  39 #define PLL_MAX_RETRY   100
  40
  41 /* Enable appropriate clocks for Ethernet */
  42 int clk_eth_enable(void)
  43 {
  44         int rc = -1;
  45         int retry_count = 0;
  46         rc = clk_get_and_enable("esub_ccu_clk");
  47
  48         /* Enable Access to CCU registers */
  49         writel((1 | WR_ACCESS_PASSWORD), WR_ACCESS_ADDR);
  50
  51         writel(readl(PLLE_POST_RESETB_ADDR) &
  52                ~PLLE_POST_RESETB_I_POST_RESETB_PLLE_MASK,
  53                PLLE_POST_RESETB_ADDR);
  54
  55         /* Take PLL out of reset and put into normal mode */
  56         writel(readl(PLLE_RESETB_ADDR) | PLLE_RESETB_I_PLL_RESETB_PLLE_MASK,
  57                PLLE_RESETB_ADDR);
  58
  59         /* Wait for PLL lock */
  60         rc = -1;
  61         while (retry_count < PLL_MAX_RETRY) {
  62                 udelay(100);
  63                 if (readl(PLL_LOCK_ADDR) & PLL_LOCK_PLL_LOCK_PLLE_MASK) {
  64                         rc = 0;
  65                         break;
  66                 }
  67                 retry_count++;
  68         }
  69
  70         if (rc == -1) {
  71                 printf("%s: ETH-PLL lock timeout, Ethernet is not enabled!\n",
  72                        __func__);
  73                 return -1;
  74         }
  75
  76         writel(readl(PLLE_POST_RESETB_ADDR) |
  77                PLLE_POST_RESETB_I_POST_RESETB_PLLE_MASK,
  78                PLLE_POST_RESETB_ADDR);
  79
  80         /* Switch esw_sys_clk to use 104MHz(208MHz/2) clock */
  81         writel((readl(ESW_SYS_DIV_ADDR) &
  82                 ~(ESW_SYS_DIV_PLL_SELECT_MASK | ESW_SYS_DIV_DIV_MASK)) |
  83                ESW_SYS_DIV_PLL_VAR_208M_CLK_SELECT | ESW_SYS_DIV_DIV_SELECT,
  84                ESW_SYS_DIV_ADDR);
  85
  86         writel(readl(ESW_SYS_DIV_ADDR) | ESW_SYS_DIV_TRIGGER_MASK,
  87                ESW_SYS_DIV_ADDR);
  88
  89         /* Wait for trigger complete */
  90         rc = -1;
  91         retry_count = 0;
  92         while (retry_count < PLL_MAX_RETRY) {
  93                 udelay(100);
  94                 if (!(readl(ESW_SYS_DIV_ADDR) & ESW_SYS_DIV_TRIGGER_MASK)) {
  95                         rc = 0;
  96                         break;
  97                 }
  98                 retry_count++;
  99         }
 100
 101         if (rc == -1) {
 102                 printf("%s: SYS CLK Trigger timeout, Ethernet is not enabled!\n",
 103                        __func__);
 104                 return -1;
 105         }
 106
 107         /* switch Esub AXI clock to 208MHz */
 108         writel((readl(ESUB_AXI_DIV_DEBUG_ADDR) &
 109                 ~(ESUB_AXI_DIV_DEBUG_PLL_SELECT_MASK |
 110                   ESUB_AXI_DIV_DEBUG_PLL_SELECT_OVERRIDE_MASK |
 111                   ESUB_AXI_DIV_DEBUG_TRIGGER_MASK)) |
 112                ESUB_AXI_DIV_DEBUG_PLL_VAR_208M_CLK_SELECT |
 113                ESUB_AXI_DIV_DEBUG_PLL_SELECT_OVERRIDE_MASK,
 114                ESUB_AXI_DIV_DEBUG_ADDR);
 115
 116         writel(readl(ESUB_AXI_DIV_DEBUG_ADDR) |
 117                ESUB_AXI_DIV_DEBUG_TRIGGER_MASK,
 118                ESUB_AXI_DIV_DEBUG_ADDR);
 119
 120         /* Wait for trigger complete */
 121         rc = -1;
 122         retry_count = 0;
 123         while (retry_count < PLL_MAX_RETRY) {
 124                 udelay(100);
 125                 if (!(readl(ESUB_AXI_DIV_DEBUG_ADDR) &
 126                       ESUB_AXI_DIV_DEBUG_TRIGGER_MASK)) {
 127                         rc = 0;
 128                         break;
 129                 }
 130                 retry_count++;
 131         }
 132
 133         if (rc == -1) {
 134                 printf("%s: AXI CLK Trigger timeout, Ethernet is not enabled!\n",
 135                        __func__);
 136                 return -1;
 137         }
 138
 139         /* Disable Access to CCU registers */
 140         writel(WR_ACCESS_PASSWORD, WR_ACCESS_ADDR);
 141
 142         return rc;
 143 }