1*ba7c8d27SÁlvaro Fernández Rojas // SPDX-License-Identifier: GPL-2.0
2*ba7c8d27SÁlvaro Fernández Rojas /*
3*ba7c8d27SÁlvaro Fernández Rojas * BCM63268 Timer Clock and Reset Controller Driver
4*ba7c8d27SÁlvaro Fernández Rojas *
5*ba7c8d27SÁlvaro Fernández Rojas * Copyright (C) 2023 Álvaro Fernández Rojas <noltari@gmail.com>
6*ba7c8d27SÁlvaro Fernández Rojas */
7*ba7c8d27SÁlvaro Fernández Rojas
8*ba7c8d27SÁlvaro Fernández Rojas #include <linux/clk-provider.h>
9*ba7c8d27SÁlvaro Fernández Rojas #include <linux/container_of.h>
10*ba7c8d27SÁlvaro Fernández Rojas #include <linux/delay.h>
11*ba7c8d27SÁlvaro Fernández Rojas #include <linux/device.h>
12*ba7c8d27SÁlvaro Fernández Rojas #include <linux/io.h>
13*ba7c8d27SÁlvaro Fernández Rojas #include <linux/platform_device.h>
14*ba7c8d27SÁlvaro Fernández Rojas #include <linux/reset-controller.h>
15*ba7c8d27SÁlvaro Fernández Rojas #include <linux/spinlock.h>
16*ba7c8d27SÁlvaro Fernández Rojas
17*ba7c8d27SÁlvaro Fernández Rojas #include <dt-bindings/clock/bcm63268-clock.h>
18*ba7c8d27SÁlvaro Fernández Rojas
19*ba7c8d27SÁlvaro Fernández Rojas #define BCM63268_TIMER_RESET_SLEEP_MIN_US 10000
20*ba7c8d27SÁlvaro Fernández Rojas #define BCM63268_TIMER_RESET_SLEEP_MAX_US 20000
21*ba7c8d27SÁlvaro Fernández Rojas
22*ba7c8d27SÁlvaro Fernández Rojas struct bcm63268_tclkrst_hw {
23*ba7c8d27SÁlvaro Fernández Rojas void __iomem *regs;
24*ba7c8d27SÁlvaro Fernández Rojas spinlock_t lock;
25*ba7c8d27SÁlvaro Fernández Rojas
26*ba7c8d27SÁlvaro Fernández Rojas struct reset_controller_dev rcdev;
27*ba7c8d27SÁlvaro Fernández Rojas struct clk_hw_onecell_data data;
28*ba7c8d27SÁlvaro Fernández Rojas };
29*ba7c8d27SÁlvaro Fernández Rojas
30*ba7c8d27SÁlvaro Fernández Rojas struct bcm63268_tclk_table_entry {
31*ba7c8d27SÁlvaro Fernández Rojas const char * const name;
32*ba7c8d27SÁlvaro Fernández Rojas u8 bit;
33*ba7c8d27SÁlvaro Fernández Rojas };
34*ba7c8d27SÁlvaro Fernández Rojas
35*ba7c8d27SÁlvaro Fernández Rojas static const struct bcm63268_tclk_table_entry bcm63268_timer_clocks[] = {
36*ba7c8d27SÁlvaro Fernández Rojas {
37*ba7c8d27SÁlvaro Fernández Rojas .name = "ephy1",
38*ba7c8d27SÁlvaro Fernández Rojas .bit = BCM63268_TCLK_EPHY1,
39*ba7c8d27SÁlvaro Fernández Rojas }, {
40*ba7c8d27SÁlvaro Fernández Rojas .name = "ephy2",
41*ba7c8d27SÁlvaro Fernández Rojas .bit = BCM63268_TCLK_EPHY2,
42*ba7c8d27SÁlvaro Fernández Rojas }, {
43*ba7c8d27SÁlvaro Fernández Rojas .name = "ephy3",
44*ba7c8d27SÁlvaro Fernández Rojas .bit = BCM63268_TCLK_EPHY3,
45*ba7c8d27SÁlvaro Fernández Rojas }, {
46*ba7c8d27SÁlvaro Fernández Rojas .name = "gphy1",
47*ba7c8d27SÁlvaro Fernández Rojas .bit = BCM63268_TCLK_GPHY1,
48*ba7c8d27SÁlvaro Fernández Rojas }, {
49*ba7c8d27SÁlvaro Fernández Rojas .name = "dsl",
50*ba7c8d27SÁlvaro Fernández Rojas .bit = BCM63268_TCLK_DSL,
51*ba7c8d27SÁlvaro Fernández Rojas }, {
52*ba7c8d27SÁlvaro Fernández Rojas .name = "wakeon_ephy",
53*ba7c8d27SÁlvaro Fernández Rojas .bit = BCM63268_TCLK_WAKEON_EPHY,
54*ba7c8d27SÁlvaro Fernández Rojas }, {
55*ba7c8d27SÁlvaro Fernández Rojas .name = "wakeon_dsl",
56*ba7c8d27SÁlvaro Fernández Rojas .bit = BCM63268_TCLK_WAKEON_DSL,
57*ba7c8d27SÁlvaro Fernández Rojas }, {
58*ba7c8d27SÁlvaro Fernández Rojas .name = "fap1_pll",
59*ba7c8d27SÁlvaro Fernández Rojas .bit = BCM63268_TCLK_FAP1,
60*ba7c8d27SÁlvaro Fernández Rojas }, {
61*ba7c8d27SÁlvaro Fernández Rojas .name = "fap2_pll",
62*ba7c8d27SÁlvaro Fernández Rojas .bit = BCM63268_TCLK_FAP2,
63*ba7c8d27SÁlvaro Fernández Rojas }, {
64*ba7c8d27SÁlvaro Fernández Rojas .name = "uto_50",
65*ba7c8d27SÁlvaro Fernández Rojas .bit = BCM63268_TCLK_UTO_50,
66*ba7c8d27SÁlvaro Fernández Rojas }, {
67*ba7c8d27SÁlvaro Fernández Rojas .name = "uto_extin",
68*ba7c8d27SÁlvaro Fernández Rojas .bit = BCM63268_TCLK_UTO_EXTIN,
69*ba7c8d27SÁlvaro Fernández Rojas }, {
70*ba7c8d27SÁlvaro Fernández Rojas .name = "usb_ref",
71*ba7c8d27SÁlvaro Fernández Rojas .bit = BCM63268_TCLK_USB_REF,
72*ba7c8d27SÁlvaro Fernández Rojas }, {
73*ba7c8d27SÁlvaro Fernández Rojas /* sentinel */
74*ba7c8d27SÁlvaro Fernández Rojas }
75*ba7c8d27SÁlvaro Fernández Rojas };
76*ba7c8d27SÁlvaro Fernández Rojas
77*ba7c8d27SÁlvaro Fernández Rojas static inline struct bcm63268_tclkrst_hw *
to_bcm63268_timer_reset(struct reset_controller_dev * rcdev)78*ba7c8d27SÁlvaro Fernández Rojas to_bcm63268_timer_reset(struct reset_controller_dev *rcdev)
79*ba7c8d27SÁlvaro Fernández Rojas {
80*ba7c8d27SÁlvaro Fernández Rojas return container_of(rcdev, struct bcm63268_tclkrst_hw, rcdev);
81*ba7c8d27SÁlvaro Fernández Rojas }
82*ba7c8d27SÁlvaro Fernández Rojas
bcm63268_timer_reset_update(struct reset_controller_dev * rcdev,unsigned long id,bool assert)83*ba7c8d27SÁlvaro Fernández Rojas static int bcm63268_timer_reset_update(struct reset_controller_dev *rcdev,
84*ba7c8d27SÁlvaro Fernández Rojas unsigned long id, bool assert)
85*ba7c8d27SÁlvaro Fernández Rojas {
86*ba7c8d27SÁlvaro Fernández Rojas struct bcm63268_tclkrst_hw *reset = to_bcm63268_timer_reset(rcdev);
87*ba7c8d27SÁlvaro Fernández Rojas unsigned long flags;
88*ba7c8d27SÁlvaro Fernández Rojas uint32_t val;
89*ba7c8d27SÁlvaro Fernández Rojas
90*ba7c8d27SÁlvaro Fernández Rojas spin_lock_irqsave(&reset->lock, flags);
91*ba7c8d27SÁlvaro Fernández Rojas val = __raw_readl(reset->regs);
92*ba7c8d27SÁlvaro Fernández Rojas if (assert)
93*ba7c8d27SÁlvaro Fernández Rojas val &= ~BIT(id);
94*ba7c8d27SÁlvaro Fernández Rojas else
95*ba7c8d27SÁlvaro Fernández Rojas val |= BIT(id);
96*ba7c8d27SÁlvaro Fernández Rojas __raw_writel(val, reset->regs);
97*ba7c8d27SÁlvaro Fernández Rojas spin_unlock_irqrestore(&reset->lock, flags);
98*ba7c8d27SÁlvaro Fernández Rojas
99*ba7c8d27SÁlvaro Fernández Rojas return 0;
100*ba7c8d27SÁlvaro Fernández Rojas }
101*ba7c8d27SÁlvaro Fernández Rojas
bcm63268_timer_reset_assert(struct reset_controller_dev * rcdev,unsigned long id)102*ba7c8d27SÁlvaro Fernández Rojas static int bcm63268_timer_reset_assert(struct reset_controller_dev *rcdev,
103*ba7c8d27SÁlvaro Fernández Rojas unsigned long id)
104*ba7c8d27SÁlvaro Fernández Rojas {
105*ba7c8d27SÁlvaro Fernández Rojas return bcm63268_timer_reset_update(rcdev, id, true);
106*ba7c8d27SÁlvaro Fernández Rojas }
107*ba7c8d27SÁlvaro Fernández Rojas
bcm63268_timer_reset_deassert(struct reset_controller_dev * rcdev,unsigned long id)108*ba7c8d27SÁlvaro Fernández Rojas static int bcm63268_timer_reset_deassert(struct reset_controller_dev *rcdev,
109*ba7c8d27SÁlvaro Fernández Rojas unsigned long id)
110*ba7c8d27SÁlvaro Fernández Rojas {
111*ba7c8d27SÁlvaro Fernández Rojas return bcm63268_timer_reset_update(rcdev, id, false);
112*ba7c8d27SÁlvaro Fernández Rojas }
113*ba7c8d27SÁlvaro Fernández Rojas
bcm63268_timer_reset_reset(struct reset_controller_dev * rcdev,unsigned long id)114*ba7c8d27SÁlvaro Fernández Rojas static int bcm63268_timer_reset_reset(struct reset_controller_dev *rcdev,
115*ba7c8d27SÁlvaro Fernández Rojas unsigned long id)
116*ba7c8d27SÁlvaro Fernández Rojas {
117*ba7c8d27SÁlvaro Fernández Rojas bcm63268_timer_reset_update(rcdev, id, true);
118*ba7c8d27SÁlvaro Fernández Rojas usleep_range(BCM63268_TIMER_RESET_SLEEP_MIN_US,
119*ba7c8d27SÁlvaro Fernández Rojas BCM63268_TIMER_RESET_SLEEP_MAX_US);
120*ba7c8d27SÁlvaro Fernández Rojas
121*ba7c8d27SÁlvaro Fernández Rojas bcm63268_timer_reset_update(rcdev, id, false);
122*ba7c8d27SÁlvaro Fernández Rojas /*
123*ba7c8d27SÁlvaro Fernández Rojas * Ensure component is taken out reset state by sleeping also after
124*ba7c8d27SÁlvaro Fernández Rojas * deasserting the reset. Otherwise, the component may not be ready
125*ba7c8d27SÁlvaro Fernández Rojas * for operation.
126*ba7c8d27SÁlvaro Fernández Rojas */
127*ba7c8d27SÁlvaro Fernández Rojas usleep_range(BCM63268_TIMER_RESET_SLEEP_MIN_US,
128*ba7c8d27SÁlvaro Fernández Rojas BCM63268_TIMER_RESET_SLEEP_MAX_US);
129*ba7c8d27SÁlvaro Fernández Rojas
130*ba7c8d27SÁlvaro Fernández Rojas return 0;
131*ba7c8d27SÁlvaro Fernández Rojas }
132*ba7c8d27SÁlvaro Fernández Rojas
bcm63268_timer_reset_status(struct reset_controller_dev * rcdev,unsigned long id)133*ba7c8d27SÁlvaro Fernández Rojas static int bcm63268_timer_reset_status(struct reset_controller_dev *rcdev,
134*ba7c8d27SÁlvaro Fernández Rojas unsigned long id)
135*ba7c8d27SÁlvaro Fernández Rojas {
136*ba7c8d27SÁlvaro Fernández Rojas struct bcm63268_tclkrst_hw *reset = to_bcm63268_timer_reset(rcdev);
137*ba7c8d27SÁlvaro Fernández Rojas
138*ba7c8d27SÁlvaro Fernández Rojas return !(__raw_readl(reset->regs) & BIT(id));
139*ba7c8d27SÁlvaro Fernández Rojas }
140*ba7c8d27SÁlvaro Fernández Rojas
141*ba7c8d27SÁlvaro Fernández Rojas static const struct reset_control_ops bcm63268_timer_reset_ops = {
142*ba7c8d27SÁlvaro Fernández Rojas .assert = bcm63268_timer_reset_assert,
143*ba7c8d27SÁlvaro Fernández Rojas .deassert = bcm63268_timer_reset_deassert,
144*ba7c8d27SÁlvaro Fernández Rojas .reset = bcm63268_timer_reset_reset,
145*ba7c8d27SÁlvaro Fernández Rojas .status = bcm63268_timer_reset_status,
146*ba7c8d27SÁlvaro Fernández Rojas };
147*ba7c8d27SÁlvaro Fernández Rojas
bcm63268_tclk_probe(struct platform_device * pdev)148*ba7c8d27SÁlvaro Fernández Rojas static int bcm63268_tclk_probe(struct platform_device *pdev)
149*ba7c8d27SÁlvaro Fernández Rojas {
150*ba7c8d27SÁlvaro Fernández Rojas struct device *dev = &pdev->dev;
151*ba7c8d27SÁlvaro Fernández Rojas const struct bcm63268_tclk_table_entry *entry;
152*ba7c8d27SÁlvaro Fernández Rojas struct bcm63268_tclkrst_hw *hw;
153*ba7c8d27SÁlvaro Fernández Rojas struct clk_hw *clk;
154*ba7c8d27SÁlvaro Fernández Rojas u8 maxbit = 0;
155*ba7c8d27SÁlvaro Fernández Rojas int i, ret;
156*ba7c8d27SÁlvaro Fernández Rojas
157*ba7c8d27SÁlvaro Fernández Rojas for (entry = bcm63268_timer_clocks; entry->name; entry++)
158*ba7c8d27SÁlvaro Fernández Rojas maxbit = max(maxbit, entry->bit);
159*ba7c8d27SÁlvaro Fernández Rojas maxbit++;
160*ba7c8d27SÁlvaro Fernández Rojas
161*ba7c8d27SÁlvaro Fernández Rojas hw = devm_kzalloc(&pdev->dev, struct_size(hw, data.hws, maxbit),
162*ba7c8d27SÁlvaro Fernández Rojas GFP_KERNEL);
163*ba7c8d27SÁlvaro Fernández Rojas if (!hw)
164*ba7c8d27SÁlvaro Fernández Rojas return -ENOMEM;
165*ba7c8d27SÁlvaro Fernández Rojas
166*ba7c8d27SÁlvaro Fernández Rojas platform_set_drvdata(pdev, hw);
167*ba7c8d27SÁlvaro Fernández Rojas
168*ba7c8d27SÁlvaro Fernández Rojas spin_lock_init(&hw->lock);
169*ba7c8d27SÁlvaro Fernández Rojas
170*ba7c8d27SÁlvaro Fernández Rojas hw->data.num = maxbit;
171*ba7c8d27SÁlvaro Fernández Rojas for (i = 0; i < maxbit; i++)
172*ba7c8d27SÁlvaro Fernández Rojas hw->data.hws[i] = ERR_PTR(-ENODEV);
173*ba7c8d27SÁlvaro Fernández Rojas
174*ba7c8d27SÁlvaro Fernández Rojas hw->regs = devm_platform_ioremap_resource(pdev, 0);
175*ba7c8d27SÁlvaro Fernández Rojas if (IS_ERR(hw->regs))
176*ba7c8d27SÁlvaro Fernández Rojas return PTR_ERR(hw->regs);
177*ba7c8d27SÁlvaro Fernández Rojas
178*ba7c8d27SÁlvaro Fernández Rojas for (entry = bcm63268_timer_clocks; entry->name; entry++) {
179*ba7c8d27SÁlvaro Fernández Rojas clk = devm_clk_hw_register_gate(dev, entry->name, NULL, 0,
180*ba7c8d27SÁlvaro Fernández Rojas hw->regs, entry->bit,
181*ba7c8d27SÁlvaro Fernández Rojas CLK_GATE_BIG_ENDIAN,
182*ba7c8d27SÁlvaro Fernández Rojas &hw->lock);
183*ba7c8d27SÁlvaro Fernández Rojas if (IS_ERR(clk))
184*ba7c8d27SÁlvaro Fernández Rojas return PTR_ERR(clk);
185*ba7c8d27SÁlvaro Fernández Rojas
186*ba7c8d27SÁlvaro Fernández Rojas hw->data.hws[entry->bit] = clk;
187*ba7c8d27SÁlvaro Fernández Rojas }
188*ba7c8d27SÁlvaro Fernández Rojas
189*ba7c8d27SÁlvaro Fernández Rojas ret = devm_of_clk_add_hw_provider(dev, of_clk_hw_onecell_get,
190*ba7c8d27SÁlvaro Fernández Rojas &hw->data);
191*ba7c8d27SÁlvaro Fernández Rojas if (ret)
192*ba7c8d27SÁlvaro Fernández Rojas return ret;
193*ba7c8d27SÁlvaro Fernández Rojas
194*ba7c8d27SÁlvaro Fernández Rojas hw->rcdev.of_node = dev->of_node;
195*ba7c8d27SÁlvaro Fernández Rojas hw->rcdev.ops = &bcm63268_timer_reset_ops;
196*ba7c8d27SÁlvaro Fernández Rojas
197*ba7c8d27SÁlvaro Fernández Rojas ret = devm_reset_controller_register(dev, &hw->rcdev);
198*ba7c8d27SÁlvaro Fernández Rojas if (ret)
199*ba7c8d27SÁlvaro Fernández Rojas dev_err(dev, "Failed to register reset controller\n");
200*ba7c8d27SÁlvaro Fernández Rojas
201*ba7c8d27SÁlvaro Fernández Rojas return 0;
202*ba7c8d27SÁlvaro Fernández Rojas }
203*ba7c8d27SÁlvaro Fernández Rojas
204*ba7c8d27SÁlvaro Fernández Rojas static const struct of_device_id bcm63268_tclk_dt_ids[] = {
205*ba7c8d27SÁlvaro Fernández Rojas { .compatible = "brcm,bcm63268-timer-clocks" },
206*ba7c8d27SÁlvaro Fernández Rojas { /* sentinel */ }
207*ba7c8d27SÁlvaro Fernández Rojas };
208*ba7c8d27SÁlvaro Fernández Rojas
209*ba7c8d27SÁlvaro Fernández Rojas static struct platform_driver bcm63268_tclk = {
210*ba7c8d27SÁlvaro Fernández Rojas .probe = bcm63268_tclk_probe,
211*ba7c8d27SÁlvaro Fernández Rojas .driver = {
212*ba7c8d27SÁlvaro Fernández Rojas .name = "bcm63268-timer-clock",
213*ba7c8d27SÁlvaro Fernández Rojas .of_match_table = bcm63268_tclk_dt_ids,
214*ba7c8d27SÁlvaro Fernández Rojas },
215*ba7c8d27SÁlvaro Fernández Rojas };
216*ba7c8d27SÁlvaro Fernández Rojas builtin_platform_driver(bcm63268_tclk);
217