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authorLinus Torvalds <torvalds@linux-foundation.org>2016-03-23 16:06:45 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2016-03-23 16:06:45 +0300
commit33c1f638a0feda92ffcb507c302482a5e6158a87 (patch)
tree57d70d2e0b56d38bd295fe439294c3c8739f4130 /drivers/clk/sunxi/clk-sun6i-ar100.c
parenta24e3d414e59ac76566dedcad1ed1d319a93ec14 (diff)
parent4d3ac6662452060721599a3392bc2f524af984cb (diff)
downloadlinux-33c1f638a0feda92ffcb507c302482a5e6158a87.tar.xz
Merge tag 'clk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux
Pull clk updates from Stephen Boyd: "The clk changes for this release cycle are mostly dominated by new device support in terms of LoC, but there has been some cleanup in the core as well as the usual minor clk additions to various drivers. Core: - parent tracking has been simplified - CLK_IS_ROOT is now a no-op flag, cleaning up drivers has started - of_clk_init() doesn't consider disabled DT nodes anymore - clk_unregister() had an error path bug squashed - of_clk_get_parent_count() has been fixed to only return unsigned ints - HAVE_MACH_CLKDEV is removed now that the last arch user (ARM) is gone New Drivers: - NXP LPC18xx creg - QCOM IPQ4019 GCC - TI dm814x ADPLL - i.MX6QP Updates: - Cyngus audio clks found on Broadcom iProc devices - Non-critical fixes for BCM2385 PLLs - Samsung exynos5433 updates for clk id errors, HDMI support, suspend/resume simplifications - USB, CAN, LVDS, and FCP clks on shmobile devices - sunxi got support for more clks on new SoCs and went through a minor refactoring/rewrite to use a simpler factor clk construct - rockchip added some more clk ids and added suport for fraction dividers - QCOM GDSCs in msm8996 - A new devm helper to make adding custom actions simpler (acked by Greg)" * tag 'clk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux: (197 commits) clk: bcm2835: fix check of error code returned by devm_ioremap_resource() clk: renesas: div6: use RENESAS for #define clk: renesas: Rename header file renesas.h clk: max77{686,802}: Remove CLK_IS_ROOT clk: versatile: Remove CLK_IS_ROOT clk: sunxi: Remove use of variable length array clk: fixed-rate: Remove CLK_IS_ROOT clk: qcom: Remove CLK_IS_ROOT doc: dt: add documentation for lpc1850-creg-clk driver clk: add lpc18xx creg clk driver clk: lpc32xx: fix compilation warning clk: xgene: Add missing parenthesis when clearing divider value clk: mb86s7x: Remove CLK_IS_ROOT clk: x86: Remove clkdev.h and clk.h includes clk: x86: Remove CLK_IS_ROOT clk: mvebu: Remove CLK_IS_ROOT clk: renesas: move drivers to renesas directory clk: si5{14,351,70}: Remove CLK_IS_ROOT clk: scpi: Remove CLK_IS_ROOT clk: s2mps11: Remove CLK_IS_ROOT ...
Diffstat (limited to 'drivers/clk/sunxi/clk-sun6i-ar100.c')
-rw-r--r--drivers/clk/sunxi/clk-sun6i-ar100.c235
1 files changed, 61 insertions, 174 deletions
diff --git a/drivers/clk/sunxi/clk-sun6i-ar100.c b/drivers/clk/sunxi/clk-sun6i-ar100.c
index 20887686bdbe..84a187e55360 100644
--- a/drivers/clk/sunxi/clk-sun6i-ar100.c
+++ b/drivers/clk/sunxi/clk-sun6i-ar100.c
@@ -8,211 +8,97 @@
*
*/
+#include <linux/bitops.h>
#include <linux/clk-provider.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
+#include <linux/spinlock.h>
-#define SUN6I_AR100_MAX_PARENTS 4
-#define SUN6I_AR100_SHIFT_MASK 0x3
-#define SUN6I_AR100_SHIFT_MAX SUN6I_AR100_SHIFT_MASK
-#define SUN6I_AR100_SHIFT_SHIFT 4
-#define SUN6I_AR100_DIV_MASK 0x1f
-#define SUN6I_AR100_DIV_MAX (SUN6I_AR100_DIV_MASK + 1)
-#define SUN6I_AR100_DIV_SHIFT 8
-#define SUN6I_AR100_MUX_MASK 0x3
-#define SUN6I_AR100_MUX_SHIFT 16
-
-struct ar100_clk {
- struct clk_hw hw;
- void __iomem *reg;
-};
-
-static inline struct ar100_clk *to_ar100_clk(struct clk_hw *hw)
-{
- return container_of(hw, struct ar100_clk, hw);
-}
-
-static unsigned long ar100_recalc_rate(struct clk_hw *hw,
- unsigned long parent_rate)
-{
- struct ar100_clk *clk = to_ar100_clk(hw);
- u32 val = readl(clk->reg);
- int shift = (val >> SUN6I_AR100_SHIFT_SHIFT) & SUN6I_AR100_SHIFT_MASK;
- int div = (val >> SUN6I_AR100_DIV_SHIFT) & SUN6I_AR100_DIV_MASK;
-
- return (parent_rate >> shift) / (div + 1);
-}
-
-static int ar100_determine_rate(struct clk_hw *hw,
- struct clk_rate_request *req)
-{
- int nparents = clk_hw_get_num_parents(hw);
- long best_rate = -EINVAL;
- int i;
-
- req->best_parent_hw = NULL;
-
- for (i = 0; i < nparents; i++) {
- unsigned long parent_rate;
- unsigned long tmp_rate;
- struct clk_hw *parent;
- unsigned long div;
- int shift;
-
- parent = clk_hw_get_parent_by_index(hw, i);
- parent_rate = clk_hw_get_rate(parent);
- div = DIV_ROUND_UP(parent_rate, req->rate);
-
- /*
- * The AR100 clk contains 2 divisors:
- * - one power of 2 divisor
- * - one regular divisor
- *
- * First check if we can safely shift (or divide by a power
- * of 2) without losing precision on the requested rate.
- */
- shift = ffs(div) - 1;
- if (shift > SUN6I_AR100_SHIFT_MAX)
- shift = SUN6I_AR100_SHIFT_MAX;
-
- div >>= shift;
-
- /*
- * Then if the divisor is still bigger than what the HW
- * actually supports, use a bigger shift (or power of 2
- * divider) value and accept to lose some precision.
- */
- while (div > SUN6I_AR100_DIV_MAX) {
- shift++;
- div >>= 1;
- if (shift > SUN6I_AR100_SHIFT_MAX)
- break;
- }
-
- /*
- * If the shift value (or power of 2 divider) is bigger
- * than what the HW actually support, skip this parent.
- */
- if (shift > SUN6I_AR100_SHIFT_MAX)
- continue;
-
- tmp_rate = (parent_rate >> shift) / div;
- if (!req->best_parent_hw || tmp_rate > best_rate) {
- req->best_parent_hw = parent;
- req->best_parent_rate = parent_rate;
- best_rate = tmp_rate;
- }
- }
-
- if (best_rate < 0)
- return best_rate;
-
- req->rate = best_rate;
-
- return 0;
-}
-
-static int ar100_set_parent(struct clk_hw *hw, u8 index)
-{
- struct ar100_clk *clk = to_ar100_clk(hw);
- u32 val = readl(clk->reg);
-
- if (index >= SUN6I_AR100_MAX_PARENTS)
- return -EINVAL;
-
- val &= ~(SUN6I_AR100_MUX_MASK << SUN6I_AR100_MUX_SHIFT);
- val |= (index << SUN6I_AR100_MUX_SHIFT);
- writel(val, clk->reg);
-
- return 0;
-}
+#include "clk-factors.h"
-static u8 ar100_get_parent(struct clk_hw *hw)
-{
- struct ar100_clk *clk = to_ar100_clk(hw);
- return (readl(clk->reg) >> SUN6I_AR100_MUX_SHIFT) &
- SUN6I_AR100_MUX_MASK;
-}
-
-static int ar100_set_rate(struct clk_hw *hw, unsigned long rate,
- unsigned long parent_rate)
+/**
+ * sun6i_get_ar100_factors - Calculates factors p, m for AR100
+ *
+ * AR100 rate is calculated as follows
+ * rate = (parent_rate >> p) / (m + 1);
+ */
+static void sun6i_get_ar100_factors(struct factors_request *req)
{
- unsigned long div = parent_rate / rate;
- struct ar100_clk *clk = to_ar100_clk(hw);
- u32 val = readl(clk->reg);
+ unsigned long div;
int shift;
- if (parent_rate % rate)
- return -EINVAL;
+ /* clock only divides */
+ if (req->rate > req->parent_rate)
+ req->rate = req->parent_rate;
- shift = ffs(div) - 1;
- if (shift > SUN6I_AR100_SHIFT_MAX)
- shift = SUN6I_AR100_SHIFT_MAX;
+ div = DIV_ROUND_UP(req->parent_rate, req->rate);
- div >>= shift;
+ if (div < 32)
+ shift = 0;
+ else if (div >> 1 < 32)
+ shift = 1;
+ else if (div >> 2 < 32)
+ shift = 2;
+ else
+ shift = 3;
- if (div > SUN6I_AR100_DIV_MAX)
- return -EINVAL;
+ div >>= shift;
- val &= ~((SUN6I_AR100_SHIFT_MASK << SUN6I_AR100_SHIFT_SHIFT) |
- (SUN6I_AR100_DIV_MASK << SUN6I_AR100_DIV_SHIFT));
- val |= (shift << SUN6I_AR100_SHIFT_SHIFT) |
- (div << SUN6I_AR100_DIV_SHIFT);
- writel(val, clk->reg);
+ if (div > 32)
+ div = 32;
- return 0;
+ req->rate = (req->parent_rate >> shift) / div;
+ req->m = div - 1;
+ req->p = shift;
}
-static struct clk_ops ar100_ops = {
- .recalc_rate = ar100_recalc_rate,
- .determine_rate = ar100_determine_rate,
- .set_parent = ar100_set_parent,
- .get_parent = ar100_get_parent,
- .set_rate = ar100_set_rate,
+static const struct clk_factors_config sun6i_ar100_config = {
+ .mwidth = 5,
+ .mshift = 8,
+ .pwidth = 2,
+ .pshift = 4,
};
+static const struct factors_data sun6i_ar100_data = {
+ .mux = 16,
+ .muxmask = GENMASK(1, 0),
+ .table = &sun6i_ar100_config,
+ .getter = sun6i_get_ar100_factors,
+};
+
+static DEFINE_SPINLOCK(sun6i_ar100_lock);
+
static int sun6i_a31_ar100_clk_probe(struct platform_device *pdev)
{
- const char *parents[SUN6I_AR100_MAX_PARENTS];
struct device_node *np = pdev->dev.of_node;
- const char *clk_name = np->name;
- struct clk_init_data init;
- struct ar100_clk *ar100;
struct resource *r;
+ void __iomem *reg;
struct clk *clk;
- int nparents;
-
- ar100 = devm_kzalloc(&pdev->dev, sizeof(*ar100), GFP_KERNEL);
- if (!ar100)
- return -ENOMEM;
r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- ar100->reg = devm_ioremap_resource(&pdev->dev, r);
- if (IS_ERR(ar100->reg))
- return PTR_ERR(ar100->reg);
+ reg = devm_ioremap_resource(&pdev->dev, r);
+ if (IS_ERR(reg))
+ return PTR_ERR(reg);
- nparents = of_clk_get_parent_count(np);
- if (nparents > SUN6I_AR100_MAX_PARENTS)
- nparents = SUN6I_AR100_MAX_PARENTS;
-
- of_clk_parent_fill(np, parents, nparents);
+ clk = sunxi_factors_register(np, &sun6i_ar100_data, &sun6i_ar100_lock,
+ reg);
+ if (!clk)
+ return -ENOMEM;
- of_property_read_string(np, "clock-output-names", &clk_name);
+ platform_set_drvdata(pdev, clk);
- init.name = clk_name;
- init.ops = &ar100_ops;
- init.parent_names = parents;
- init.num_parents = nparents;
- init.flags = 0;
+ return 0;
+}
- ar100->hw.init = &init;
+static int sun6i_a31_ar100_clk_remove(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ struct clk *clk = platform_get_drvdata(pdev);
- clk = clk_register(&pdev->dev, &ar100->hw);
- if (IS_ERR(clk))
- return PTR_ERR(clk);
+ sunxi_factors_unregister(np, clk);
- return of_clk_add_provider(np, of_clk_src_simple_get, clk);
+ return 0;
}
static const struct of_device_id sun6i_a31_ar100_clk_dt_ids[] = {
@@ -227,6 +113,7 @@ static struct platform_driver sun6i_a31_ar100_clk_driver = {
.of_match_table = sun6i_a31_ar100_clk_dt_ids,
},
.probe = sun6i_a31_ar100_clk_probe,
+ .remove = sun6i_a31_ar100_clk_remove,
};
module_platform_driver(sun6i_a31_ar100_clk_driver);