1 // SPDX-License-Identifier: BSD-3-Clause
2 /*
3  * Clock drivers for Qualcomm APQ8016, APQ8096
4  *
5  * (C) Copyright 2015 Mateusz Kulikowski <mateusz.kulikowski@gmail.com>
6  *
7  * Based on Little Kernel driver, simplified
8  */
9 
10 #include <common.h>
11 #include <clk-uclass.h>
12 #include <dm.h>
13 #include <errno.h>
14 #include <asm/io.h>
15 #include <linux/bitops.h>
16 #include "clock-snapdragon.h"
17 
18 /* CBCR register fields */
19 #define CBCR_BRANCH_ENABLE_BIT  BIT(0)
20 #define CBCR_BRANCH_OFF_BIT     BIT(31)
21 
22 extern ulong msm_set_rate(struct clk *clk, ulong rate);
23 extern int msm_enable(struct clk *clk);
24 
25 /* Enable clock controlled by CBC soft macro */
clk_enable_cbc(phys_addr_t cbcr)26 void clk_enable_cbc(phys_addr_t cbcr)
27 {
28 	setbits_le32(cbcr, CBCR_BRANCH_ENABLE_BIT);
29 
30 	while (readl(cbcr) & CBCR_BRANCH_OFF_BIT)
31 		;
32 }
33 
clk_enable_gpll0(phys_addr_t base,const struct pll_vote_clk * gpll0)34 void clk_enable_gpll0(phys_addr_t base, const struct pll_vote_clk *gpll0)
35 {
36 	if (readl(base + gpll0->status) & gpll0->status_bit)
37 		return; /* clock already enabled */
38 
39 	setbits_le32(base + gpll0->ena_vote, gpll0->vote_bit);
40 
41 	while ((readl(base + gpll0->status) & gpll0->status_bit) == 0)
42 		;
43 }
44 
45 #define BRANCH_ON_VAL (0)
46 #define BRANCH_NOC_FSM_ON_VAL BIT(29)
47 #define BRANCH_CHECK_MASK GENMASK(31, 28)
48 
clk_enable_vote_clk(phys_addr_t base,const struct vote_clk * vclk)49 void clk_enable_vote_clk(phys_addr_t base, const struct vote_clk *vclk)
50 {
51 	u32 val;
52 
53 	setbits_le32(base + vclk->ena_vote, vclk->vote_bit);
54 	do {
55 		val = readl(base + vclk->cbcr_reg);
56 		val &= BRANCH_CHECK_MASK;
57 	} while ((val != BRANCH_ON_VAL) && (val != BRANCH_NOC_FSM_ON_VAL));
58 }
59 
60 #define APPS_CMD_RCGR_UPDATE BIT(0)
61 
62 /* Update clock command via CMD_RCGR */
clk_bcr_update(phys_addr_t apps_cmd_rcgr)63 void clk_bcr_update(phys_addr_t apps_cmd_rcgr)
64 {
65 	setbits_le32(apps_cmd_rcgr, APPS_CMD_RCGR_UPDATE);
66 
67 	/* Wait for frequency to be updated. */
68 	while (readl(apps_cmd_rcgr) & APPS_CMD_RCGR_UPDATE)
69 		;
70 }
71 
72 #define CFG_MODE_DUAL_EDGE (0x2 << 12) /* Counter mode */
73 
74 #define CFG_MASK 0x3FFF
75 
76 #define CFG_DIVIDER_MASK 0x1F
77 
78 /* root set rate for clocks with half integer and MND divider */
clk_rcg_set_rate_mnd(phys_addr_t base,const struct bcr_regs * regs,int div,int m,int n,int source)79 void clk_rcg_set_rate_mnd(phys_addr_t base, const struct bcr_regs *regs,
80 			  int div, int m, int n, int source)
81 {
82 	u32 cfg;
83 	/* M value for MND divider. */
84 	u32 m_val = m;
85 	/* NOT(N-M) value for MND divider. */
86 	u32 n_val = ~((n) - (m)) * !!(n);
87 	/* NOT 2D value for MND divider. */
88 	u32 d_val = ~(n);
89 
90 	/* Program MND values */
91 	writel(m_val, base + regs->M);
92 	writel(n_val, base + regs->N);
93 	writel(d_val, base + regs->D);
94 
95 	/* setup src select and divider */
96 	cfg  = readl(base + regs->cfg_rcgr);
97 	cfg &= ~CFG_MASK;
98 	cfg |= source & CFG_CLK_SRC_MASK; /* Select clock source */
99 
100 	/* Set the divider; HW permits fraction dividers (+0.5), but
101 	   for simplicity, we will support integers only */
102 	if (div)
103 		cfg |= (2 * div - 1) & CFG_DIVIDER_MASK;
104 
105 	if (n_val)
106 		cfg |= CFG_MODE_DUAL_EDGE;
107 
108 	writel(cfg, base + regs->cfg_rcgr); /* Write new clock configuration */
109 
110 	/* Inform h/w to start using the new config. */
111 	clk_bcr_update(base + regs->cmd_rcgr);
112 }
113 
114 /* root set rate for clocks with half integer and mnd_width=0 */
clk_rcg_set_rate(phys_addr_t base,const struct bcr_regs * regs,int div,int source)115 void clk_rcg_set_rate(phys_addr_t base, const struct bcr_regs *regs, int div,
116 		      int source)
117 {
118 	u32 cfg;
119 
120 	/* setup src select and divider */
121 	cfg  = readl(base + regs->cfg_rcgr);
122 	cfg &= ~CFG_MASK;
123 	cfg |= source & CFG_CLK_SRC_MASK; /* Select clock source */
124 
125 	/*
126 	 * Set the divider; HW permits fraction dividers (+0.5), but
127 	 * for simplicity, we will support integers only
128 	 */
129 	if (div)
130 		cfg |= (2 * div - 1) & CFG_DIVIDER_MASK;
131 
132 	writel(cfg, base + regs->cfg_rcgr); /* Write new clock configuration */
133 
134 	/* Inform h/w to start using the new config. */
135 	clk_bcr_update(base + regs->cmd_rcgr);
136 }
137 
msm_clk_probe(struct udevice * dev)138 static int msm_clk_probe(struct udevice *dev)
139 {
140 	struct msm_clk_priv *priv = dev_get_priv(dev);
141 
142 	priv->base = dev_read_addr(dev);
143 	if (priv->base == FDT_ADDR_T_NONE)
144 		return -EINVAL;
145 
146 	return 0;
147 }
148 
msm_clk_set_rate(struct clk * clk,ulong rate)149 static ulong msm_clk_set_rate(struct clk *clk, ulong rate)
150 {
151 	return msm_set_rate(clk, rate);
152 }
153 
msm_clk_enable(struct clk * clk)154 static int msm_clk_enable(struct clk *clk)
155 {
156 	return msm_enable(clk);
157 }
158 
159 static struct clk_ops msm_clk_ops = {
160 	.set_rate = msm_clk_set_rate,
161 	.enable = msm_clk_enable,
162 };
163 
164 static const struct udevice_id msm_clk_ids[] = {
165 	{ .compatible = "qcom,gcc-msm8916" },
166 	{ .compatible = "qcom,gcc-apq8016" },
167 	{ .compatible = "qcom,gcc-msm8996" },
168 	{ .compatible = "qcom,gcc-apq8096" },
169 	{ .compatible = "qcom,gcc-sdm845" },
170 	{ .compatible = "qcom,gcc-qcs404" },
171 	{ }
172 };
173 
174 U_BOOT_DRIVER(clk_msm) = {
175 	.name		= "clk_msm",
176 	.id		= UCLASS_CLK,
177 	.of_match	= msm_clk_ids,
178 	.ops		= &msm_clk_ops,
179 	.priv_auto	= sizeof(struct msm_clk_priv),
180 	.probe		= msm_clk_probe,
181 };
182