xref: /openbmc/u-boot/arch/mips/mach-pic32/cpu.c (revision e11ef3d2)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2015
4  * Purna Chandra Mandal <purna.mandal@microchip.com>
5  *
6  */
7 #include <common.h>
8 #include <clk.h>
9 #include <dm.h>
10 #include <mach/pic32.h>
11 #include <mach/ddr.h>
12 #include <dt-bindings/clock/microchip,clock.h>
13 
14 /* Flash prefetch */
15 #define PRECON          0x00
16 
17 /* Flash ECCCON */
18 #define ECC_MASK	0x03
19 #define ECC_SHIFT	4
20 
21 #define CLK_MHZ(x)	((x) / 1000000)
22 
23 DECLARE_GLOBAL_DATA_PTR;
24 
25 static ulong rate(int id)
26 {
27 	int ret;
28 	struct udevice *dev;
29 	struct clk clk;
30 	ulong rate;
31 
32 	ret = uclass_get_device(UCLASS_CLK, 0, &dev);
33 	if (ret) {
34 		printf("clk-uclass not found\n");
35 		return 0;
36 	}
37 
38 	clk.id = id;
39 	ret = clk_request(dev, &clk);
40 	if (ret < 0)
41 		return ret;
42 
43 	rate = clk_get_rate(&clk);
44 
45 	clk_free(&clk);
46 
47 	return rate;
48 }
49 
50 static ulong clk_get_cpu_rate(void)
51 {
52 	return rate(PB7CLK);
53 }
54 
55 /* initialize prefetch module related to cpu_clk */
56 static void prefetch_init(void)
57 {
58 	struct pic32_reg_atomic *regs;
59 	const void __iomem *base;
60 	int v, nr_waits;
61 	ulong rate;
62 
63 	/* cpu frequency in MHZ */
64 	rate = clk_get_cpu_rate() / 1000000;
65 
66 	/* get flash ECC type */
67 	base = pic32_get_syscfg_base();
68 	v = (readl(base + CFGCON) >> ECC_SHIFT) & ECC_MASK;
69 
70 	if (v < 2) {
71 		if (rate < 66)
72 			nr_waits = 0;
73 		else if (rate < 133)
74 			nr_waits = 1;
75 		else
76 			nr_waits = 2;
77 	} else {
78 		if (rate <= 83)
79 			nr_waits = 0;
80 		else if (rate <= 166)
81 			nr_waits = 1;
82 		else
83 			nr_waits = 2;
84 	}
85 
86 	regs = ioremap(PREFETCH_BASE + PRECON, sizeof(*regs));
87 	writel(nr_waits, &regs->raw);
88 
89 	/* Enable prefetch for all */
90 	writel(0x30, &regs->set);
91 	iounmap(regs);
92 }
93 
94 /* arch specific CPU init after DM */
95 int arch_cpu_init_dm(void)
96 {
97 	/* flash prefetch */
98 	prefetch_init();
99 	return 0;
100 }
101 
102 /* Un-gate DDR2 modules (gated by default) */
103 static void ddr2_pmd_ungate(void)
104 {
105 	void __iomem *regs;
106 
107 	regs = pic32_get_syscfg_base();
108 	writel(0, regs + PMD7);
109 }
110 
111 /* initialize the DDR2 Controller and DDR2 PHY */
112 int dram_init(void)
113 {
114 	ddr2_pmd_ungate();
115 	ddr2_phy_init();
116 	ddr2_ctrl_init();
117 	gd->ram_size = ddr2_calculate_size();
118 
119 	return 0;
120 }
121 
122 int misc_init_r(void)
123 {
124 	set_io_port_base(0);
125 	return 0;
126 }
127 
128 #ifdef CONFIG_DISPLAY_BOARDINFO
129 const char *get_core_name(void)
130 {
131 	u32 proc_id;
132 	const char *str;
133 
134 	proc_id = read_c0_prid();
135 	switch (proc_id) {
136 	case 0x19e28:
137 		str = "PIC32MZ[DA]";
138 		break;
139 	default:
140 		str = "UNKNOWN";
141 	}
142 
143 	return str;
144 }
145 #endif
146 #ifdef CONFIG_CMD_CLK
147 
148 int soc_clk_dump(void)
149 {
150 	int i;
151 
152 	printf("PLL Speed: %lu MHz\n",
153 	       CLK_MHZ(rate(PLLCLK)));
154 
155 	printf("CPU Speed: %lu MHz\n", CLK_MHZ(rate(PB7CLK)));
156 
157 	printf("MPLL Speed: %lu MHz\n", CLK_MHZ(rate(MPLL)));
158 
159 	for (i = PB1CLK; i <= PB7CLK; i++)
160 		printf("PB%d Clock Speed: %lu MHz\n", i - PB1CLK + 1,
161 		       CLK_MHZ(rate(i)));
162 
163 	for (i = REF1CLK; i <= REF5CLK; i++)
164 		printf("REFO%d Clock Speed: %lu MHz\n", i - REF1CLK + 1,
165 		       CLK_MHZ(rate(i)));
166 	return 0;
167 }
168 #endif
169