Add support for the Dove PLL dividers, which are used to generate the clocks for the AXI bus, as well as the GPU and VMeta peripherals. Signed-off-by: Russell King <rmk+kernel@xxxxxxxxxxxxxxxx> --- drivers/clk/mvebu/Makefile | 2 +- drivers/clk/mvebu/dove-divider.c | 262 +++++++++++++++++++++++++++++++++++++++ drivers/clk/mvebu/dove.c | 6 + 3 files changed, 269 insertions(+), 1 deletion(-) create mode 100644 drivers/clk/mvebu/dove-divider.c diff --git a/drivers/clk/mvebu/Makefile b/drivers/clk/mvebu/Makefile index 645ac7ea3565..8866115486f7 100644 --- a/drivers/clk/mvebu/Makefile +++ b/drivers/clk/mvebu/Makefile @@ -7,6 +7,6 @@ obj-$(CONFIG_ARMADA_375_CLK) += armada-375.o obj-$(CONFIG_ARMADA_38X_CLK) += armada-38x.o obj-$(CONFIG_ARMADA_39X_CLK) += armada-39x.o obj-$(CONFIG_ARMADA_XP_CLK) += armada-xp.o -obj-$(CONFIG_DOVE_CLK) += dove.o +obj-$(CONFIG_DOVE_CLK) += dove.o dove-divider.o obj-$(CONFIG_KIRKWOOD_CLK) += kirkwood.o obj-$(CONFIG_ORION_CLK) += orion.o diff --git a/drivers/clk/mvebu/dove-divider.c b/drivers/clk/mvebu/dove-divider.c new file mode 100644 index 000000000000..0478184d7a28 --- /dev/null +++ b/drivers/clk/mvebu/dove-divider.c @@ -0,0 +1,262 @@ +/* + * Marvell Dove PMU Core PLL divider driver + * + * Cleaned up by substantially rewriting, and converted to DT by + * Russell King. Origin is not known. + */ +#include <linux/clk-provider.h> +#include <linux/delay.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/of.h> +#include <linux/of_address.h> + +#include "dove-divider.h" + +struct dove_clk { + const char *name; + struct clk_hw hw; + void __iomem *base; + spinlock_t *lock; + u8 div_bit_start; + u8 div_bit_end; + u8 div_bit_load; + u8 div_bit_size; + u32 *divider_table; +}; + +enum { + DIV_CTRL0 = 0, + DIV_CTRL1 = 4, + DIV_CTRL1_N_RESET_MASK = BIT(10), +}; + +#define to_dove_clk(hw) container_of(hw, struct dove_clk, hw) + +static void dove_load_divider(void __iomem *base, u32 val, u32 mask, u32 load) +{ + u32 v; + + v = readl_relaxed(base + DIV_CTRL1) | DIV_CTRL1_N_RESET_MASK; + writel_relaxed(v, base + DIV_CTRL1); + + v = (readl_relaxed(base + DIV_CTRL0) & ~(mask | load)) | val; + writel_relaxed(v, base + DIV_CTRL0); + writel_relaxed(v | load, base + DIV_CTRL0); + ndelay(250); + writel_relaxed(v, base + DIV_CTRL0); +} + +static unsigned int dove_get_divider(struct dove_clk *dc) +{ + unsigned int divider; + u32 val; + + val = readl_relaxed(dc->base + DIV_CTRL0); + val >>= dc->div_bit_start; + + divider = val & ~(~0 << dc->div_bit_size); + + if (dc->divider_table) + divider = dc->divider_table[divider]; + + return divider; +} + +static int dove_calc_divider(const struct dove_clk *dc, unsigned long rate, + unsigned long parent_rate, bool set) +{ + unsigned int divider, max; + + divider = DIV_ROUND_CLOSEST(parent_rate, rate); + + if (dc->divider_table) { + unsigned int i; + + for (i = 0; dc->divider_table[i]; i++) + if (divider == dc->divider_table[i]) { + divider = i; + break; + } + + if (dc->divider_table[i]) + return -EINVAL; + } else { + max = 1 << dc->div_bit_size; + + if (set && (divider == 0 || divider >= max)) + return -EINVAL; + if (divider >= max) + divider = max - 1; + else if (divider == 0) + divider = 1; + } + + return divider; +} + +static unsigned long dove_recalc_rate(struct clk_hw *hw, unsigned long parent) +{ + struct dove_clk *dc = to_dove_clk(hw); + unsigned int divider = dove_get_divider(dc); + unsigned long rate = DIV_ROUND_CLOSEST(parent, divider); + + pr_debug("%s(): %s divider=%u parent=%lu rate=%lu\n", + __func__, dc->name, divider, parent, rate); + + return rate; +} + +static long dove_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *parent) +{ + struct dove_clk *dc = to_dove_clk(hw); + unsigned long parent_rate = *parent; + int divider; + + divider = dove_calc_divider(dc, rate, parent_rate, false); + if (divider < 0) + return divider; + + rate = DIV_ROUND_CLOSEST(parent_rate, divider); + + pr_debug("%s(): %s divider=%u parent=%lu rate=%lu\n", + __func__, dc->name, divider, parent_rate, rate); + + return rate; +} + +static int dove_set_clock(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct dove_clk *dc = to_dove_clk(hw); + u32 mask, load, div; + int divider; + + divider = dove_calc_divider(dc, rate, parent_rate, true); + if (divider < 0) + return divider; + + pr_debug("%s(): %s divider=%u parent=%lu rate=%lu\n", + __func__, dc->name, divider, parent_rate, rate); + + div = (u32)divider << dc->div_bit_start; + mask = ~(~0 << dc->div_bit_size) << dc->div_bit_start; + load = BIT(dc->div_bit_load); + + spin_lock(dc->lock); + dove_load_divider(dc->base, div, mask, load); + spin_unlock(dc->lock); + + return 0; +} + +static const struct clk_ops dove_divider_ops = { + .set_rate = dove_set_clock, + .round_rate = dove_round_rate, + .recalc_rate = dove_recalc_rate, +}; + +static struct clk *clk_register_dove_divider(struct device *dev, + struct dove_clk *dc, const char **parent_names, size_t num_parents, + void __iomem *base) +{ + char name[32]; + struct clk_init_data init = { + .name = name, + .ops = &dove_divider_ops, + .parent_names = parent_names, + .num_parents = num_parents, + }; + + strlcpy(name, dc->name, sizeof(name)); + + dc->hw.init = &init; + dc->base = base; + dc->div_bit_size = dc->div_bit_end - dc->div_bit_start + 1; + + return clk_register(dev, &dc->hw); +} + +static DEFINE_SPINLOCK(dove_divider_lock); + +static u32 axi_divider[] = {-1, 2, 1, 3, 4, 6, 5, 7, 8, 10, 9, 0}; + +static struct dove_clk dove_hw_clocks[4] = { + { + .name = "axi", + .lock = &dove_divider_lock, + .div_bit_start = 1, + .div_bit_end = 6, + .div_bit_load = 7, + .divider_table = axi_divider, + }, { + .name = "gpu", + .lock = &dove_divider_lock, + .div_bit_start = 8, + .div_bit_end = 13, + .div_bit_load = 14, + }, { + .name = "vmeta", + .lock = &dove_divider_lock, + .div_bit_start = 15, + .div_bit_end = 20, + .div_bit_load = 21, + }, { + .name = "lcd", + .lock = &dove_divider_lock, + .div_bit_start = 22, + .div_bit_end = 27, + .div_bit_load = 28, + }, +}; + +static const char *core_pll[] = { + "core-pll", +}; + +static int dove_divider_init(struct device *dev, void __iomem *base, + struct clk **clks) +{ + struct clk *clk; + int i; + + /* + * Create the core PLL clock. We treat this as a fixed rate + * clock as we don't know any better, and documentation is sparse. + */ + clk = clk_register_fixed_rate(dev, core_pll[0], NULL, CLK_IS_ROOT, + 2000000000UL); + if (IS_ERR(clk)) + return PTR_ERR(clk); + + for (i = 0; i < ARRAY_SIZE(dove_hw_clocks); i++) + clks[i] = clk_register_dove_divider(dev, &dove_hw_clocks[i], + core_pll, + ARRAY_SIZE(core_pll), base); + + return 0; +} + +static struct clk *dove_divider_clocks[4]; + +static struct clk_onecell_data dove_divider_data = { + .clks = dove_divider_clocks, + .clk_num = ARRAY_SIZE(dove_divider_clocks), +}; + +void __init dove_divider_clk_init(struct device_node *np) +{ + void *base; + + base = of_iomap(np, 0); + if (WARN_ON(!base)) + return; + + if (WARN_ON(dove_divider_init(NULL, base, dove_divider_clocks))) { + iounmap(base); + return; + } + + of_clk_add_provider(np, of_clk_src_onecell_get, &dove_divider_data); +} diff --git a/drivers/clk/mvebu/dove.c b/drivers/clk/mvebu/dove.c index b8c2424ac926..59fad9546c84 100644 --- a/drivers/clk/mvebu/dove.c +++ b/drivers/clk/mvebu/dove.c @@ -17,6 +17,7 @@ #include <linux/io.h> #include <linux/of.h> #include "common.h" +#include "dove-divider.h" /* * Core Clocks @@ -184,9 +185,14 @@ static void __init dove_clk_init(struct device_node *np) { struct device_node *cgnp = of_find_compatible_node(NULL, NULL, "marvell,dove-gating-clock"); + struct device_node *ddnp = + of_find_compatible_node(NULL, NULL, "marvell,dove-divider-clock"); mvebu_coreclk_setup(np, &dove_coreclks); + if (ddnp) + dove_divider_clk_init(ddnp); + if (cgnp) mvebu_clk_gating_setup(cgnp, dove_gating_desc); } -- 2.1.0 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html