xref: /openbmc/u-boot/arch/mips/mach-pic32/cpu.c (revision b24a8ec1)
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 int dram_init(void)
114 {
115 	ddr2_pmd_ungate();
116 	ddr2_phy_init();
117 	ddr2_ctrl_init();
118 	gd->ram_size = ddr2_calculate_size();
119 
120 	return 0;
121 }
122 
123 int misc_init_r(void)
124 {
125 	set_io_port_base(0);
126 	return 0;
127 }
128 
129 #ifdef CONFIG_DISPLAY_BOARDINFO
130 const char *get_core_name(void)
131 {
132 	u32 proc_id;
133 	const char *str;
134 
135 	proc_id = read_c0_prid();
136 	switch (proc_id) {
137 	case 0x19e28:
138 		str = "PIC32MZ[DA]";
139 		break;
140 	default:
141 		str = "UNKNOWN";
142 	}
143 
144 	return str;
145 }
146 #endif
147 #ifdef CONFIG_CMD_CLK
148 
149 int soc_clk_dump(void)
150 {
151 	int i;
152 
153 	printf("PLL Speed: %lu MHz\n",
154 	       CLK_MHZ(rate(PLLCLK)));
155 
156 	printf("CPU Speed: %lu MHz\n", CLK_MHZ(rate(PB7CLK)));
157 
158 	printf("MPLL Speed: %lu MHz\n", CLK_MHZ(rate(MPLL)));
159 
160 	for (i = PB1CLK; i <= PB7CLK; i++)
161 		printf("PB%d Clock Speed: %lu MHz\n", i - PB1CLK + 1,
162 		       CLK_MHZ(rate(i)));
163 
164 	for (i = REF1CLK; i <= REF5CLK; i++)
165 		printf("REFO%d Clock Speed: %lu MHz\n", i - REF1CLK + 1,
166 		       CLK_MHZ(rate(i)));
167 	return 0;
168 }
169 #endif
170