diff options
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/clk/axs10x/Makefile | 1 | ||||
-rw-r--r-- | drivers/clk/axs10x/pll_clock.c | 346 |
2 files changed, 347 insertions, 0 deletions
diff --git a/drivers/clk/axs10x/Makefile b/drivers/clk/axs10x/Makefile index 01996b871b06..d747deafbf1e 100644 --- a/drivers/clk/axs10x/Makefile +++ b/drivers/clk/axs10x/Makefile @@ -1 +1,2 @@ obj-y += i2s_pll_clock.o +obj-y += pll_clock.o diff --git a/drivers/clk/axs10x/pll_clock.c b/drivers/clk/axs10x/pll_clock.c new file mode 100644 index 000000000000..25d8c240ddfb --- /dev/null +++ b/drivers/clk/axs10x/pll_clock.c @@ -0,0 +1,346 @@ +/* + * Synopsys AXS10X SDP Generic PLL clock driver + * + * Copyright (C) 2017 Synopsys + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ + +#include <linux/platform_device.h> +#include <linux/module.h> +#include <linux/clk-provider.h> +#include <linux/delay.h> +#include <linux/err.h> +#include <linux/device.h> +#include <linux/of_address.h> +#include <linux/of_device.h> +#include <linux/slab.h> +#include <linux/of.h> + +/* PLL registers addresses */ +#define PLL_REG_IDIV 0x0 +#define PLL_REG_FBDIV 0x4 +#define PLL_REG_ODIV 0x8 + +/* + * Bit fields of the PLL IDIV/FBDIV/ODIV registers: + * ________________________________________________________________________ + * |31 15| 14 | 13 | 12 |11 6|5 0| + * |-------RESRVED------|-NOUPDATE-|-BYPASS-|-EDGE-|--HIGHTIME--|--LOWTIME--| + * |____________________|__________|________|______|____________|___________| + * + * Following macros determine the way of access to these registers + * They should be set up only using the macros. + * reg should be an u32 variable. + */ + +#define PLL_REG_GET_LOW(reg) \ + (((reg) & (0x3F << 0)) >> 0) +#define PLL_REG_GET_HIGH(reg) \ + (((reg) & (0x3F << 6)) >> 6) +#define PLL_REG_GET_EDGE(reg) \ + (((reg) & (BIT(12))) ? 1 : 0) +#define PLL_REG_GET_BYPASS(reg) \ + (((reg) & (BIT(13))) ? 1 : 0) +#define PLL_REG_GET_NOUPD(reg) \ + (((reg) & (BIT(14))) ? 1 : 0) +#define PLL_REG_GET_PAD(reg) \ + (((reg) & (0x1FFFF << 15)) >> 15) + +#define PLL_REG_SET_LOW(reg, value) \ + { reg |= (((value) & 0x3F) << 0); } +#define PLL_REG_SET_HIGH(reg, value) \ + { reg |= (((value) & 0x3F) << 6); } +#define PLL_REG_SET_EDGE(reg, value) \ + { reg |= (((value) & 0x01) << 12); } +#define PLL_REG_SET_BYPASS(reg, value) \ + { reg |= (((value) & 0x01) << 13); } +#define PLL_REG_SET_NOUPD(reg, value) \ + { reg |= (((value) & 0x01) << 14); } +#define PLL_REG_SET_PAD(reg, value) \ + { reg |= (((value) & 0x1FFFF) << 15); } + +#define PLL_LOCK BIT(0) +#define PLL_ERROR BIT(1) +#define PLL_MAX_LOCK_TIME 100 /* 100 us */ + +struct axs10x_pll_cfg { + u32 rate; + u32 idiv; + u32 fbdiv; + u32 odiv; +}; + +static const struct axs10x_pll_cfg arc_pll_cfg[] = { + { 33333333, 1, 1, 1 }, + { 50000000, 1, 30, 20 }, + { 75000000, 2, 45, 10 }, + { 90000000, 2, 54, 10 }, + { 100000000, 1, 30, 10 }, + { 125000000, 2, 45, 6 }, + {} +}; + +static const struct axs10x_pll_cfg pgu_pll_cfg[] = { + { 25200000, 1, 84, 90 }, + { 50000000, 1, 100, 54 }, + { 74250000, 1, 44, 16 }, + {} +}; + +struct axs10x_pll_clk { + struct clk_hw hw; + void __iomem *base; + void __iomem *lock; + const struct axs10x_pll_cfg *pll_cfg; + struct device *dev; +}; + +static inline void axs10x_pll_write(struct axs10x_pll_clk *clk, u32 reg, + u32 val) +{ + iowrite32(val, clk->base + reg); +} + +static inline u32 axs10x_pll_read(struct axs10x_pll_clk *clk, u32 reg) +{ + return ioread32(clk->base + reg); +} + +static inline struct axs10x_pll_clk *to_axs10x_pll_clk(struct clk_hw *hw) +{ + return container_of(hw, struct axs10x_pll_clk, hw); +} + +static inline u32 axs10x_div_get_value(u32 reg) +{ + if (PLL_REG_GET_BYPASS(reg)) + return 1; + + return PLL_REG_GET_HIGH(reg) + PLL_REG_GET_LOW(reg); +} + +static inline u32 axs10x_encode_div(unsigned int id, int upd) +{ + u32 div = 0; + + PLL_REG_SET_LOW(div, (id % 2 == 0) ? id >> 1 : (id >> 1) + 1); + PLL_REG_SET_HIGH(div, id >> 1); + PLL_REG_SET_EDGE(div, id % 2); + PLL_REG_SET_BYPASS(div, id == 1 ? 1 : 0); + PLL_REG_SET_NOUPD(div, upd == 0 ? 1 : 0); + + return div; +} + +static unsigned long axs10x_pll_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + u64 rate; + u32 idiv, fbdiv, odiv; + struct axs10x_pll_clk *clk = to_axs10x_pll_clk(hw); + + idiv = axs10x_div_get_value(axs10x_pll_read(clk, PLL_REG_IDIV)); + fbdiv = axs10x_div_get_value(axs10x_pll_read(clk, PLL_REG_FBDIV)); + odiv = axs10x_div_get_value(axs10x_pll_read(clk, PLL_REG_ODIV)); + + rate = (u64)parent_rate * fbdiv; + do_div(rate, idiv * odiv); + + return rate; +} + +static long axs10x_pll_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *prate) +{ + int i; + long best_rate; + struct axs10x_pll_clk *clk = to_axs10x_pll_clk(hw); + const struct axs10x_pll_cfg *pll_cfg = clk->pll_cfg; + + if (pll_cfg[0].rate == 0) + return -EINVAL; + + best_rate = pll_cfg[0].rate; + + for (i = 1; pll_cfg[i].rate != 0; i++) { + if (abs(rate - pll_cfg[i].rate) < abs(rate - best_rate)) + best_rate = pll_cfg[i].rate; + } + + return best_rate; +} + +static int axs10x_pll_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + int i; + struct axs10x_pll_clk *clk = to_axs10x_pll_clk(hw); + const struct axs10x_pll_cfg *pll_cfg = clk->pll_cfg; + + for (i = 0; pll_cfg[i].rate != 0; i++) { + if (pll_cfg[i].rate == rate) { + axs10x_pll_write(clk, PLL_REG_IDIV, + axs10x_encode_div(pll_cfg[i].idiv, 0)); + axs10x_pll_write(clk, PLL_REG_FBDIV, + axs10x_encode_div(pll_cfg[i].fbdiv, 0)); + axs10x_pll_write(clk, PLL_REG_ODIV, + axs10x_encode_div(pll_cfg[i].odiv, 1)); + + /* + * Wait until CGU relocks and check error status. + * If after timeout CGU is unlocked yet return error + */ + udelay(PLL_MAX_LOCK_TIME); + if (!(ioread32(clk->lock) & PLL_LOCK)) + return -ETIMEDOUT; + + if (ioread32(clk->lock) & PLL_ERROR) + return -EINVAL; + + return 0; + } + } + + dev_err(clk->dev, "invalid rate=%ld, parent_rate=%ld\n", rate, + parent_rate); + return -EINVAL; +} + +static const struct clk_ops axs10x_pll_ops = { + .recalc_rate = axs10x_pll_recalc_rate, + .round_rate = axs10x_pll_round_rate, + .set_rate = axs10x_pll_set_rate, +}; + +static int axs10x_pll_clk_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + const char *parent_name; + struct axs10x_pll_clk *pll_clk; + struct resource *mem; + struct clk_init_data init = { }; + int ret; + + pll_clk = devm_kzalloc(dev, sizeof(*pll_clk), GFP_KERNEL); + if (!pll_clk) + return -ENOMEM; + + mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); + pll_clk->base = devm_ioremap_resource(dev, mem); + if (IS_ERR(pll_clk->base)) + return PTR_ERR(pll_clk->base); + + mem = platform_get_resource(pdev, IORESOURCE_MEM, 1); + pll_clk->lock = devm_ioremap_resource(dev, mem); + if (IS_ERR(pll_clk->lock)) + return PTR_ERR(pll_clk->lock); + + init.name = dev->of_node->name; + init.ops = &axs10x_pll_ops; + parent_name = of_clk_get_parent_name(dev->of_node, 0); + init.parent_names = &parent_name; + init.num_parents = 1; + pll_clk->hw.init = &init; + pll_clk->dev = dev; + pll_clk->pll_cfg = of_device_get_match_data(dev); + + if (!pll_clk->pll_cfg) { + dev_err(dev, "No OF match data provided\n"); + return -EINVAL; + } + + ret = devm_clk_hw_register(dev, &pll_clk->hw); + if (ret) { + dev_err(dev, "failed to register %s clock\n", init.name); + return ret; + } + + return of_clk_add_hw_provider(dev->of_node, of_clk_hw_simple_get, + &pll_clk->hw); +} + +static int axs10x_pll_clk_remove(struct platform_device *pdev) +{ + of_clk_del_provider(pdev->dev.of_node); + return 0; +} + +static void __init of_axs10x_pll_clk_setup(struct device_node *node) +{ + const char *parent_name; + struct axs10x_pll_clk *pll_clk; + struct clk_init_data init = { }; + int ret; + + pll_clk = kzalloc(sizeof(*pll_clk), GFP_KERNEL); + if (!pll_clk) + return; + + pll_clk->base = of_iomap(node, 0); + if (!pll_clk->base) { + pr_err("failed to map pll div registers\n"); + goto err_free_pll_clk; + } + + pll_clk->lock = of_iomap(node, 1); + if (!pll_clk->lock) { + pr_err("failed to map pll lock register\n"); + goto err_unmap_base; + } + + init.name = node->name; + init.ops = &axs10x_pll_ops; + parent_name = of_clk_get_parent_name(node, 0); + init.parent_names = &parent_name; + init.num_parents = parent_name ? 1 : 0; + pll_clk->hw.init = &init; + pll_clk->pll_cfg = arc_pll_cfg; + + ret = clk_hw_register(NULL, &pll_clk->hw); + if (ret) { + pr_err("failed to register %s clock\n", node->name); + goto err_unmap_lock; + } + + ret = of_clk_add_hw_provider(node, of_clk_hw_simple_get, &pll_clk->hw); + if (ret) { + pr_err("failed to add hw provider for %s clock\n", node->name); + goto err_unregister_clk; + } + + return; + +err_unregister_clk: + clk_hw_unregister(&pll_clk->hw); +err_unmap_lock: + iounmap(pll_clk->lock); +err_unmap_base: + iounmap(pll_clk->base); +err_free_pll_clk: + kfree(pll_clk); +} +CLK_OF_DECLARE(axs10x_pll_clock, "snps,axs10x-arc-pll-clock", + of_axs10x_pll_clk_setup); + +static const struct of_device_id axs10x_pll_clk_id[] = { + { .compatible = "snps,axs10x-pgu-pll-clock", .data = &pgu_pll_cfg}, + { } +}; +MODULE_DEVICE_TABLE(of, axs10x_pll_clk_id); + +static struct platform_driver axs10x_pll_clk_driver = { + .driver = { + .name = "axs10x-pll-clock", + .of_match_table = axs10x_pll_clk_id, + }, + .probe = axs10x_pll_clk_probe, + .remove = axs10x_pll_clk_remove, +}; +builtin_platform_driver(axs10x_pll_clk_driver); + +MODULE_AUTHOR("Vlad Zakharov <vzakhar@synopsys.com>"); +MODULE_DESCRIPTION("Synopsys AXS10X SDP Generic PLL Clock Driver"); +MODULE_LICENSE("GPL v2"); |