1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright 2014 Broadcom Corporation.
4  */
5 
6 #include <common.h>
7 #include <asm/io.h>
8 #include <linux/delay.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 */
clk_eth_enable(void)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 }
144