Liviu Dudau | ba024e6 | 2018-09-17 17:50:00 +0100 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0+ |
| 2 | /* |
| 3 | * Copyright (C) 2018 Arm Ltd |
| 4 | * Author: Liviu Dudau <liviu.dudau@foss.arm.com> |
| 5 | * |
| 6 | */ |
| 7 | #define DEBUG |
Tom Rini | abb9a04 | 2024-05-18 20:20:43 -0600 | [diff] [blame] | 8 | #include <common.h> |
Liviu Dudau | ba024e6 | 2018-09-17 17:50:00 +0100 | [diff] [blame] | 9 | #include <clk-uclass.h> |
| 10 | #include <dm.h> |
Simon Glass | 0f2af88 | 2020-05-10 11:40:05 -0600 | [diff] [blame] | 11 | #include <log.h> |
Simon Glass | 9bc1564 | 2020-02-03 07:36:16 -0700 | [diff] [blame] | 12 | #include <dm/device_compat.h> |
Liviu Dudau | ba024e6 | 2018-09-17 17:50:00 +0100 | [diff] [blame] | 13 | #include <dm/lists.h> |
| 14 | #include <errno.h> |
| 15 | #include <misc.h> |
Simon Glass | 4dcacfc | 2020-05-10 11:40:13 -0600 | [diff] [blame] | 16 | #include <linux/bitops.h> |
Liviu Dudau | ba024e6 | 2018-09-17 17:50:00 +0100 | [diff] [blame] | 17 | |
| 18 | #define CLK_FUNCTION BIT(20) |
| 19 | |
| 20 | struct vexpress_osc_clk_priv { |
| 21 | u8 osc; |
| 22 | ulong rate_min; |
| 23 | ulong rate_max; |
| 24 | }; |
| 25 | |
| 26 | static ulong vexpress_osc_clk_get_rate(struct clk *clk) |
| 27 | { |
| 28 | int err; |
| 29 | u32 data; |
| 30 | struct udevice *vexpress_cfg = dev_get_parent(clk->dev); |
| 31 | struct vexpress_osc_clk_priv *priv = dev_get_priv(clk->dev); |
| 32 | |
| 33 | data = CLK_FUNCTION | priv->osc; |
| 34 | err = misc_read(vexpress_cfg, 0, &data, sizeof(data)); |
Simon Glass | 587dc40 | 2018-11-06 15:21:39 -0700 | [diff] [blame] | 35 | if (err < 0) |
Liviu Dudau | ba024e6 | 2018-09-17 17:50:00 +0100 | [diff] [blame] | 36 | return err; |
| 37 | |
| 38 | return data; |
| 39 | } |
| 40 | |
| 41 | #ifndef CONFIG_SPL_BUILD |
| 42 | static ulong vexpress_osc_clk_set_rate(struct clk *clk, ulong rate) |
| 43 | { |
| 44 | int err; |
| 45 | u32 buffer[2]; |
| 46 | struct udevice *vexpress_cfg = dev_get_parent(clk->dev); |
| 47 | struct vexpress_osc_clk_priv *priv = dev_get_priv(clk->dev); |
| 48 | |
| 49 | if (rate < priv->rate_min || rate > priv->rate_max) |
| 50 | return -EINVAL; |
| 51 | |
| 52 | /* |
| 53 | * we are sending the parent the info about the oscillator |
| 54 | * and the value we want to set |
| 55 | */ |
| 56 | buffer[0] = CLK_FUNCTION | priv->osc; |
| 57 | buffer[1] = rate; |
| 58 | err = misc_write(vexpress_cfg, 0, buffer, 2 * sizeof(u32)); |
Simon Glass | 587dc40 | 2018-11-06 15:21:39 -0700 | [diff] [blame] | 59 | if (err < 0) |
Liviu Dudau | ba024e6 | 2018-09-17 17:50:00 +0100 | [diff] [blame] | 60 | return err; |
| 61 | |
| 62 | return rate; |
| 63 | } |
| 64 | #endif |
| 65 | |
| 66 | static struct clk_ops vexpress_osc_clk_ops = { |
| 67 | .get_rate = vexpress_osc_clk_get_rate, |
| 68 | #ifndef CONFIG_SPL_BUILD |
| 69 | .set_rate = vexpress_osc_clk_set_rate, |
| 70 | #endif |
| 71 | }; |
| 72 | |
| 73 | static int vexpress_osc_clk_probe(struct udevice *dev) |
| 74 | { |
| 75 | struct vexpress_osc_clk_priv *priv = dev_get_priv(dev); |
| 76 | u32 values[2]; |
| 77 | int err; |
| 78 | |
| 79 | err = dev_read_u32_array(dev, "freq-range", values, 2); |
| 80 | if (err) |
| 81 | return err; |
| 82 | priv->rate_min = values[0]; |
| 83 | priv->rate_max = values[1]; |
| 84 | |
| 85 | err = dev_read_u32_array(dev, "arm,vexpress-sysreg,func", values, 2); |
| 86 | if (err) |
| 87 | return err; |
| 88 | |
| 89 | if (values[0] != 1) { |
| 90 | dev_err(dev, "Invalid VExpress function for clock, must be '1'"); |
| 91 | return -EINVAL; |
| 92 | } |
| 93 | priv->osc = values[1]; |
| 94 | debug("clk \"%s%d\", min freq %luHz, max freq %luHz\n", dev->name, |
| 95 | priv->osc, priv->rate_min, priv->rate_max); |
| 96 | |
| 97 | return 0; |
| 98 | } |
| 99 | |
| 100 | static const struct udevice_id vexpress_osc_clk_ids[] = { |
| 101 | { .compatible = "arm,vexpress-osc", }, |
| 102 | {} |
| 103 | }; |
| 104 | |
| 105 | U_BOOT_DRIVER(vexpress_osc_clk) = { |
| 106 | .name = "vexpress_osc_clk", |
| 107 | .id = UCLASS_CLK, |
| 108 | .of_match = vexpress_osc_clk_ids, |
| 109 | .ops = &vexpress_osc_clk_ops, |
Simon Glass | 8a2b47f | 2020-12-03 16:55:17 -0700 | [diff] [blame] | 110 | .priv_auto = sizeof(struct vexpress_osc_clk_priv), |
Liviu Dudau | ba024e6 | 2018-09-17 17:50:00 +0100 | [diff] [blame] | 111 | .probe = vexpress_osc_clk_probe, |
| 112 | }; |