Greg Kroah-Hartman | b244131 | 2017-11-01 15:07:57 +0100 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0 |
Martin Fuzzey | 75f83d0 | 2013-04-23 20:16:59 +0800 | [diff] [blame] | 2 | #include <linux/clk.h> |
| 3 | #include <linux/err.h> |
| 4 | #include <linux/of.h> |
| 5 | #include <linux/slab.h> |
Sascha Hauer | 3a84d17 | 2012-09-11 08:50:00 +0200 | [diff] [blame] | 6 | #include <linux/spinlock.h> |
Fabio Estevam | 41921c1 | 2013-03-25 09:20:38 -0300 | [diff] [blame] | 7 | #include "clk.h" |
Sascha Hauer | 3a84d17 | 2012-09-11 08:50:00 +0200 | [diff] [blame] | 8 | |
| 9 | DEFINE_SPINLOCK(imx_ccm_lock); |
Martin Fuzzey | 75f83d0 | 2013-04-23 20:16:59 +0800 | [diff] [blame] | 10 | |
Alexander Shiyan | 229be9c | 2014-06-10 19:40:26 +0400 | [diff] [blame] | 11 | void __init imx_check_clocks(struct clk *clks[], unsigned int count) |
| 12 | { |
| 13 | unsigned i; |
| 14 | |
| 15 | for (i = 0; i < count; i++) |
| 16 | if (IS_ERR(clks[i])) |
| 17 | pr_err("i.MX clk %u: register failed with %ld\n", |
| 18 | i, PTR_ERR(clks[i])); |
| 19 | } |
| 20 | |
Martin Fuzzey | 75f83d0 | 2013-04-23 20:16:59 +0800 | [diff] [blame] | 21 | static struct clk * __init imx_obtain_fixed_clock_from_dt(const char *name) |
| 22 | { |
Fabio Estevam | cc27cce | 2013-05-24 16:55:42 -0300 | [diff] [blame] | 23 | struct of_phandle_args phandle; |
Martin Fuzzey | 75f83d0 | 2013-04-23 20:16:59 +0800 | [diff] [blame] | 24 | struct clk *clk = ERR_PTR(-ENODEV); |
| 25 | char *path; |
| 26 | |
| 27 | path = kasprintf(GFP_KERNEL, "/clocks/%s", name); |
| 28 | if (!path) |
| 29 | return ERR_PTR(-ENOMEM); |
| 30 | |
| 31 | phandle.np = of_find_node_by_path(path); |
| 32 | kfree(path); |
| 33 | |
| 34 | if (phandle.np) { |
| 35 | clk = of_clk_get_from_provider(&phandle); |
| 36 | of_node_put(phandle.np); |
| 37 | } |
| 38 | return clk; |
| 39 | } |
| 40 | |
| 41 | struct clk * __init imx_obtain_fixed_clock( |
| 42 | const char *name, unsigned long rate) |
| 43 | { |
| 44 | struct clk *clk; |
| 45 | |
| 46 | clk = imx_obtain_fixed_clock_from_dt(name); |
| 47 | if (IS_ERR(clk)) |
| 48 | clk = imx_clk_fixed(name, rate); |
| 49 | return clk; |
| 50 | } |
Liu Ying | dfd8714 | 2013-07-04 17:57:17 +0800 | [diff] [blame] | 51 | |
| 52 | /* |
| 53 | * This fixups the register CCM_CSCMR1 write value. |
| 54 | * The write/read/divider values of the aclk_podf field |
| 55 | * of that register have the relationship described by |
| 56 | * the following table: |
| 57 | * |
| 58 | * write value read value divider |
| 59 | * 3b'000 3b'110 7 |
| 60 | * 3b'001 3b'111 8 |
| 61 | * 3b'010 3b'100 5 |
| 62 | * 3b'011 3b'101 6 |
| 63 | * 3b'100 3b'010 3 |
| 64 | * 3b'101 3b'011 4 |
| 65 | * 3b'110 3b'000 1 |
| 66 | * 3b'111 3b'001 2(default) |
| 67 | * |
| 68 | * That's why we do the xor operation below. |
| 69 | */ |
| 70 | #define CSCMR1_FIXUP 0x00600000 |
| 71 | |
| 72 | void imx_cscmr1_fixup(u32 *val) |
| 73 | { |
| 74 | *val ^= CSCMR1_FIXUP; |
| 75 | return; |
| 76 | } |
Lucas Stach | 55adc61 | 2015-09-21 18:53:57 +0200 | [diff] [blame] | 77 | |
| 78 | static int imx_keep_uart_clocks __initdata; |
| 79 | static struct clk ** const *imx_uart_clocks __initdata; |
| 80 | |
| 81 | static int __init imx_keep_uart_clocks_param(char *str) |
| 82 | { |
| 83 | imx_keep_uart_clocks = 1; |
| 84 | |
| 85 | return 0; |
| 86 | } |
| 87 | __setup_param("earlycon", imx_keep_uart_earlycon, |
| 88 | imx_keep_uart_clocks_param, 0); |
| 89 | __setup_param("earlyprintk", imx_keep_uart_earlyprintk, |
| 90 | imx_keep_uart_clocks_param, 0); |
| 91 | |
| 92 | void __init imx_register_uart_clocks(struct clk ** const clks[]) |
| 93 | { |
| 94 | if (imx_keep_uart_clocks) { |
| 95 | int i; |
| 96 | |
| 97 | imx_uart_clocks = clks; |
| 98 | for (i = 0; imx_uart_clocks[i]; i++) |
| 99 | clk_prepare_enable(*imx_uart_clocks[i]); |
| 100 | } |
| 101 | } |
| 102 | |
| 103 | static int __init imx_clk_disable_uart(void) |
| 104 | { |
| 105 | if (imx_keep_uart_clocks && imx_uart_clocks) { |
| 106 | int i; |
| 107 | |
| 108 | for (i = 0; imx_uart_clocks[i]; i++) |
| 109 | clk_disable_unprepare(*imx_uart_clocks[i]); |
| 110 | } |
| 111 | |
| 112 | return 0; |
| 113 | } |
| 114 | late_initcall_sync(imx_clk_disable_uart); |