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Diffstat (limited to 'arch/arm/mach-omap2/dpll3xxx.c')
-rw-r--r--arch/arm/mach-omap2/dpll3xxx.c179
1 files changed, 119 insertions, 60 deletions
diff --git a/arch/arm/mach-omap2/dpll3xxx.c b/arch/arm/mach-omap2/dpll3xxx.c
index ac3d789ac3c..20e120d071d 100644
--- a/arch/arm/mach-omap2/dpll3xxx.c
+++ b/arch/arm/mach-omap2/dpll3xxx.c
@@ -460,25 +460,24 @@ void omap3_noncore_dpll_disable(struct clk_hw *hw)
/* Non-CORE DPLL rate set code */
/**
- * omap3_noncore_dpll_set_rate - set non-core DPLL rate
- * @clk: struct clk * of DPLL to set
- * @rate: rounded target rate
+ * omap3_noncore_dpll_determine_rate - determine rate for a DPLL
+ * @hw: pointer to the clock to determine rate for
+ * @rate: target rate for the DPLL
+ * @best_parent_rate: pointer for returning best parent rate
+ * @best_parent_clk: pointer for returning best parent clock
*
- * Set the DPLL CLKOUT to the target rate. If the DPLL can enter
- * low-power bypass, and the target rate is the bypass source clock
- * rate, then configure the DPLL for bypass. Otherwise, round the
- * target rate if it hasn't been done already, then program and lock
- * the DPLL. Returns -EINVAL upon error, or 0 upon success.
+ * Determines which DPLL mode to use for reaching a desired target rate.
+ * Checks whether the DPLL shall be in bypass or locked mode, and if
+ * locked, calculates the M,N values for the DPLL via round-rate.
+ * Returns a positive clock rate with success, negative error value
+ * in failure.
*/
-int omap3_noncore_dpll_set_rate(struct clk_hw *hw, unsigned long rate,
- unsigned long parent_rate)
+long omap3_noncore_dpll_determine_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *best_parent_rate,
+ struct clk **best_parent_clk)
{
struct clk_hw_omap *clk = to_clk_hw_omap(hw);
- struct clk *new_parent = NULL;
- unsigned long rrate;
- u16 freqsel = 0;
struct dpll_data *dd;
- int ret;
if (!hw || !rate)
return -EINVAL;
@@ -489,61 +488,121 @@ int omap3_noncore_dpll_set_rate(struct clk_hw *hw, unsigned long rate,
if (__clk_get_rate(dd->clk_bypass) == rate &&
(dd->modes & (1 << DPLL_LOW_POWER_BYPASS))) {
- pr_debug("%s: %s: set rate: entering bypass.\n",
- __func__, __clk_get_name(hw->clk));
+ *best_parent_clk = dd->clk_bypass;
+ } else {
+ rate = omap2_dpll_round_rate(hw, rate, best_parent_rate);
+ *best_parent_clk = dd->clk_ref;
+ }
+
+ *best_parent_rate = rate;
+
+ return rate;
+}
+
+/**
+ * omap3_noncore_dpll_set_parent - set parent for a DPLL clock
+ * @hw: pointer to the clock to set parent for
+ * @index: parent index to select
+ *
+ * Sets parent for a DPLL clock. This sets the DPLL into bypass or
+ * locked mode. Returns 0 with success, negative error value otherwise.
+ */
+int omap3_noncore_dpll_set_parent(struct clk_hw *hw, u8 index)
+{
+ struct clk_hw_omap *clk = to_clk_hw_omap(hw);
+ int ret;
- __clk_prepare(dd->clk_bypass);
- clk_enable(dd->clk_bypass);
+ if (!hw)
+ return -EINVAL;
+
+ if (index)
ret = _omap3_noncore_dpll_bypass(clk);
- if (!ret)
- new_parent = dd->clk_bypass;
- clk_disable(dd->clk_bypass);
- __clk_unprepare(dd->clk_bypass);
- } else {
- __clk_prepare(dd->clk_ref);
- clk_enable(dd->clk_ref);
-
- /* XXX this check is probably pointless in the CCF context */
- if (dd->last_rounded_rate != rate) {
- rrate = __clk_round_rate(hw->clk, rate);
- if (rrate != rate) {
- pr_warn("%s: %s: final rate %lu does not match desired rate %lu\n",
- __func__, __clk_get_name(hw->clk),
- rrate, rate);
- rate = rrate;
- }
- }
+ else
+ ret = _omap3_noncore_dpll_lock(clk);
- if (dd->last_rounded_rate == 0)
- return -EINVAL;
+ return ret;
+}
- /* Freqsel is available only on OMAP343X devices */
- if (ti_clk_features.flags & TI_CLK_DPLL_HAS_FREQSEL) {
- freqsel = _omap3_dpll_compute_freqsel(clk,
- dd->last_rounded_n);
- WARN_ON(!freqsel);
- }
+/**
+ * omap3_noncore_dpll_set_rate - set rate for a DPLL clock
+ * @hw: pointer to the clock to set parent for
+ * @rate: target rate for the clock
+ * @parent_rate: rate of the parent clock
+ *
+ * Sets rate for a DPLL clock. First checks if the clock parent is
+ * reference clock (in bypass mode, the rate of the clock can't be
+ * changed) and proceeds with the rate change operation. Returns 0
+ * with success, negative error value otherwise.
+ */
+int omap3_noncore_dpll_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct clk_hw_omap *clk = to_clk_hw_omap(hw);
+ struct dpll_data *dd;
+ u16 freqsel = 0;
+ int ret;
+
+ if (!hw || !rate)
+ return -EINVAL;
+
+ dd = clk->dpll_data;
+ if (!dd)
+ return -EINVAL;
- pr_debug("%s: %s: set rate: locking rate to %lu.\n",
- __func__, __clk_get_name(hw->clk), rate);
+ if (__clk_get_parent(hw->clk) != dd->clk_ref)
+ return -EINVAL;
+
+ if (dd->last_rounded_rate == 0)
+ return -EINVAL;
- ret = omap3_noncore_dpll_program(clk, freqsel);
- if (!ret)
- new_parent = dd->clk_ref;
- clk_disable(dd->clk_ref);
- __clk_unprepare(dd->clk_ref);
+ /* Freqsel is available only on OMAP343X devices */
+ if (ti_clk_features.flags & TI_CLK_DPLL_HAS_FREQSEL) {
+ freqsel = _omap3_dpll_compute_freqsel(clk, dd->last_rounded_n);
+ WARN_ON(!freqsel);
}
- /*
- * FIXME - this is all wrong. common code handles reparenting and
- * migrating prepare/enable counts. dplls should be a multiplexer
- * clock and this should be a set_parent operation so that all of that
- * stuff is inherited for free
- */
- if (!ret && clk_get_parent(hw->clk) != new_parent)
- __clk_reparent(hw->clk, new_parent);
+ pr_debug("%s: %s: set rate: locking rate to %lu.\n", __func__,
+ __clk_get_name(hw->clk), rate);
- return 0;
+ ret = omap3_noncore_dpll_program(clk, freqsel);
+
+ return ret;
+}
+
+/**
+ * omap3_noncore_dpll_set_rate_and_parent - set rate and parent for a DPLL clock
+ * @hw: pointer to the clock to set rate and parent for
+ * @rate: target rate for the DPLL
+ * @parent_rate: clock rate of the DPLL parent
+ * @index: new parent index for the DPLL, 0 - reference, 1 - bypass
+ *
+ * Sets rate and parent for a DPLL clock. If new parent is the bypass
+ * clock, only selects the parent. Otherwise proceeds with a rate
+ * change, as this will effectively also change the parent as the
+ * DPLL is put into locked mode. Returns 0 with success, negative error
+ * value otherwise.
+ */
+int omap3_noncore_dpll_set_rate_and_parent(struct clk_hw *hw,
+ unsigned long rate,
+ unsigned long parent_rate,
+ u8 index)
+{
+ int ret;
+
+ if (!hw || !rate)
+ return -EINVAL;
+
+ /*
+ * clk-ref at index[0], in which case we only need to set rate,
+ * the parent will be changed automatically with the lock sequence.
+ * With clk-bypass case we only need to change parent.
+ */
+ if (index)
+ ret = omap3_noncore_dpll_set_parent(hw, index);
+ else
+ ret = omap3_noncore_dpll_set_rate(hw, rate, parent_rate);
+
+ return ret;
}
/* DPLL autoidle read/set code */