diff options
Diffstat (limited to 'drivers/clk/mvebu/armada-37xx-tbg.c')
| -rw-r--r-- | drivers/clk/mvebu/armada-37xx-tbg.c | 157 |
1 files changed, 157 insertions, 0 deletions
diff --git a/drivers/clk/mvebu/armada-37xx-tbg.c b/drivers/clk/mvebu/armada-37xx-tbg.c new file mode 100644 index 000000000..585a02e0b --- /dev/null +++ b/drivers/clk/mvebu/armada-37xx-tbg.c @@ -0,0 +1,157 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Marvell Armada 37xx SoC Time Base Generator clocks + * + * Copyright (C) 2016 Marvell + * + * Gregory CLEMENT <gregory.clement@free-electrons.com> + */ + +#include <linux/clk-provider.h> +#include <linux/clk.h> +#include <linux/io.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/platform_device.h> +#include <linux/slab.h> + +#define NUM_TBG 4 + +#define TBG_CTRL0 0x4 +#define TBG_CTRL1 0x8 +#define TBG_CTRL7 0x20 +#define TBG_CTRL8 0x30 + +#define TBG_DIV_MASK 0x1FF + +#define TBG_A_REFDIV 0 +#define TBG_B_REFDIV 16 + +#define TBG_A_FBDIV 2 +#define TBG_B_FBDIV 18 + +#define TBG_A_VCODIV_SE 0 +#define TBG_B_VCODIV_SE 16 + +#define TBG_A_VCODIV_DIFF 1 +#define TBG_B_VCODIV_DIFF 17 + +struct tbg_def { + char *name; + u32 refdiv_offset; + u32 fbdiv_offset; + u32 vcodiv_reg; + u32 vcodiv_offset; +}; + +static const struct tbg_def tbg[NUM_TBG] = { + {"TBG-A-P", TBG_A_REFDIV, TBG_A_FBDIV, TBG_CTRL8, TBG_A_VCODIV_DIFF}, + {"TBG-B-P", TBG_B_REFDIV, TBG_B_FBDIV, TBG_CTRL8, TBG_B_VCODIV_DIFF}, + {"TBG-A-S", TBG_A_REFDIV, TBG_A_FBDIV, TBG_CTRL1, TBG_A_VCODIV_SE}, + {"TBG-B-S", TBG_B_REFDIV, TBG_B_FBDIV, TBG_CTRL1, TBG_B_VCODIV_SE}, +}; + +static unsigned int tbg_get_mult(void __iomem *reg, const struct tbg_def *ptbg) +{ + u32 val; + + val = readl(reg + TBG_CTRL0); + + return ((val >> ptbg->fbdiv_offset) & TBG_DIV_MASK) << 2; +} + +static unsigned int tbg_get_div(void __iomem *reg, const struct tbg_def *ptbg) +{ + u32 val; + unsigned int div; + + val = readl(reg + TBG_CTRL7); + + div = (val >> ptbg->refdiv_offset) & TBG_DIV_MASK; + if (div == 0) + div = 1; + val = readl(reg + ptbg->vcodiv_reg); + + div *= 1 << ((val >> ptbg->vcodiv_offset) & TBG_DIV_MASK); + + return div; +} + + +static int armada_3700_tbg_clock_probe(struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + struct clk_hw_onecell_data *hw_tbg_data; + struct device *dev = &pdev->dev; + const char *parent_name; + struct resource *res; + struct clk *parent; + void __iomem *reg; + int i, ret; + + hw_tbg_data = devm_kzalloc(&pdev->dev, + struct_size(hw_tbg_data, hws, NUM_TBG), + GFP_KERNEL); + if (!hw_tbg_data) + return -ENOMEM; + hw_tbg_data->num = NUM_TBG; + platform_set_drvdata(pdev, hw_tbg_data); + + parent = clk_get(dev, NULL); + if (IS_ERR(parent)) { + dev_err(dev, "Could get the clock parent\n"); + return -EINVAL; + } + parent_name = __clk_get_name(parent); + clk_put(parent); + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + reg = devm_ioremap_resource(dev, res); + if (IS_ERR(reg)) + return PTR_ERR(reg); + + for (i = 0; i < NUM_TBG; i++) { + const char *name; + unsigned int mult, div; + + name = tbg[i].name; + mult = tbg_get_mult(reg, &tbg[i]); + div = tbg_get_div(reg, &tbg[i]); + hw_tbg_data->hws[i] = clk_hw_register_fixed_factor(NULL, name, + parent_name, 0, mult, div); + if (IS_ERR(hw_tbg_data->hws[i])) + dev_err(dev, "Can't register TBG clock %s\n", name); + } + + ret = of_clk_add_hw_provider(np, of_clk_hw_onecell_get, hw_tbg_data); + + return ret; +} + +static int armada_3700_tbg_clock_remove(struct platform_device *pdev) +{ + int i; + struct clk_hw_onecell_data *hw_tbg_data = platform_get_drvdata(pdev); + + of_clk_del_provider(pdev->dev.of_node); + for (i = 0; i < hw_tbg_data->num; i++) + clk_hw_unregister_fixed_factor(hw_tbg_data->hws[i]); + + return 0; +} + +static const struct of_device_id armada_3700_tbg_clock_of_match[] = { + { .compatible = "marvell,armada-3700-tbg-clock", }, + { } +}; + +static struct platform_driver armada_3700_tbg_clock_driver = { + .probe = armada_3700_tbg_clock_probe, + .remove = armada_3700_tbg_clock_remove, + .driver = { + .name = "marvell-armada-3700-tbg-clock", + .of_match_table = armada_3700_tbg_clock_of_match, + }, +}; + +builtin_platform_driver(armada_3700_tbg_clock_driver); |