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Diffstat (limited to 'drivers/clk/ti/clkt_dflt.c')
-rw-r--r--drivers/clk/ti/clkt_dflt.c316
1 files changed, 316 insertions, 0 deletions
diff --git a/drivers/clk/ti/clkt_dflt.c b/drivers/clk/ti/clkt_dflt.c
new file mode 100644
index 000000000000..90d7d8a21c49
--- /dev/null
+++ b/drivers/clk/ti/clkt_dflt.c
@@ -0,0 +1,316 @@
+/*
+ * Default clock type
+ *
+ * Copyright (C) 2005-2008, 2015 Texas Instruments, Inc.
+ * Copyright (C) 2004-2010 Nokia Corporation
+ *
+ * Contacts:
+ * Richard Woodruff <r-woodruff2@ti.com>
+ * Paul Walmsley
+ * Tero Kristo <t-kristo@ti.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any
+ * kind, whether express or implied; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/clk-provider.h>
+#include <linux/io.h>
+#include <linux/clk/ti.h>
+#include <linux/delay.h>
+
+#include "clock.h"
+
+/*
+ * MAX_MODULE_ENABLE_WAIT: maximum of number of microseconds to wait
+ * for a module to indicate that it is no longer in idle
+ */
+#define MAX_MODULE_ENABLE_WAIT 100000
+
+/*
+ * CM module register offsets, used for calculating the companion
+ * register addresses.
+ */
+#define CM_FCLKEN 0x0000
+#define CM_ICLKEN 0x0010
+
+/**
+ * _wait_idlest_generic - wait for a module to leave the idle state
+ * @clk: module clock to wait for (needed for register offsets)
+ * @reg: virtual address of module IDLEST register
+ * @mask: value to mask against to determine if the module is active
+ * @idlest: idle state indicator (0 or 1) for the clock
+ * @name: name of the clock (for printk)
+ *
+ * Wait for a module to leave idle, where its idle-status register is
+ * not inside the CM module. Returns 1 if the module left idle
+ * promptly, or 0 if the module did not leave idle before the timeout
+ * elapsed. XXX Deprecated - should be moved into drivers for the
+ * individual IP block that the IDLEST register exists in.
+ */
+static int _wait_idlest_generic(struct clk_hw_omap *clk, void __iomem *reg,
+ u32 mask, u8 idlest, const char *name)
+{
+ int i = 0, ena = 0;
+
+ ena = (idlest) ? 0 : mask;
+
+ /* Wait until module enters enabled state */
+ for (i = 0; i < MAX_MODULE_ENABLE_WAIT; i++) {
+ if ((ti_clk_ll_ops->clk_readl(reg) & mask) == ena)
+ break;
+ udelay(1);
+ }
+
+ if (i < MAX_MODULE_ENABLE_WAIT)
+ pr_debug("omap clock: module associated with clock %s ready after %d loops\n",
+ name, i);
+ else
+ pr_err("omap clock: module associated with clock %s didn't enable in %d tries\n",
+ name, MAX_MODULE_ENABLE_WAIT);
+
+ return (i < MAX_MODULE_ENABLE_WAIT) ? 1 : 0;
+}
+
+/**
+ * _omap2_module_wait_ready - wait for an OMAP module to leave IDLE
+ * @clk: struct clk * belonging to the module
+ *
+ * If the necessary clocks for the OMAP hardware IP block that
+ * corresponds to clock @clk are enabled, then wait for the module to
+ * indicate readiness (i.e., to leave IDLE). This code does not
+ * belong in the clock code and will be moved in the medium term to
+ * module-dependent code. No return value.
+ */
+static void _omap2_module_wait_ready(struct clk_hw_omap *clk)
+{
+ void __iomem *companion_reg, *idlest_reg;
+ u8 other_bit, idlest_bit, idlest_val, idlest_reg_id;
+ s16 prcm_mod;
+ int r;
+
+ /* Not all modules have multiple clocks that their IDLEST depends on */
+ if (clk->ops->find_companion) {
+ clk->ops->find_companion(clk, &companion_reg, &other_bit);
+ if (!(ti_clk_ll_ops->clk_readl(companion_reg) &
+ (1 << other_bit)))
+ return;
+ }
+
+ clk->ops->find_idlest(clk, &idlest_reg, &idlest_bit, &idlest_val);
+ r = ti_clk_ll_ops->cm_split_idlest_reg(idlest_reg, &prcm_mod,
+ &idlest_reg_id);
+ if (r) {
+ /* IDLEST register not in the CM module */
+ _wait_idlest_generic(clk, idlest_reg, (1 << idlest_bit),
+ idlest_val, clk_hw_get_name(&clk->hw));
+ } else {
+ ti_clk_ll_ops->cm_wait_module_ready(0, prcm_mod, idlest_reg_id,
+ idlest_bit);
+ }
+}
+
+/**
+ * omap2_clk_dflt_find_companion - find companion clock to @clk
+ * @clk: struct clk * to find the companion clock of
+ * @other_reg: void __iomem ** to return the companion clock CM_*CLKEN va in
+ * @other_bit: u8 ** to return the companion clock bit shift in
+ *
+ * Note: We don't need special code here for INVERT_ENABLE for the
+ * time being since INVERT_ENABLE only applies to clocks enabled by
+ * CM_CLKEN_PLL
+ *
+ * Convert CM_ICLKEN* <-> CM_FCLKEN*. This conversion assumes it's
+ * just a matter of XORing the bits.
+ *
+ * Some clocks don't have companion clocks. For example, modules with
+ * only an interface clock (such as MAILBOXES) don't have a companion
+ * clock. Right now, this code relies on the hardware exporting a bit
+ * in the correct companion register that indicates that the
+ * nonexistent 'companion clock' is active. Future patches will
+ * associate this type of code with per-module data structures to
+ * avoid this issue, and remove the casts. No return value.
+ */
+void omap2_clk_dflt_find_companion(struct clk_hw_omap *clk,
+ void __iomem **other_reg, u8 *other_bit)
+{
+ u32 r;
+
+ /*
+ * Convert CM_ICLKEN* <-> CM_FCLKEN*. This conversion assumes
+ * it's just a matter of XORing the bits.
+ */
+ r = ((__force u32)clk->enable_reg ^ (CM_FCLKEN ^ CM_ICLKEN));
+
+ *other_reg = (__force void __iomem *)r;
+ *other_bit = clk->enable_bit;
+}
+
+/**
+ * omap2_clk_dflt_find_idlest - find CM_IDLEST reg va, bit shift for @clk
+ * @clk: struct clk * to find IDLEST info for
+ * @idlest_reg: void __iomem ** to return the CM_IDLEST va in
+ * @idlest_bit: u8 * to return the CM_IDLEST bit shift in
+ * @idlest_val: u8 * to return the idle status indicator
+ *
+ * Return the CM_IDLEST register address and bit shift corresponding
+ * to the module that "owns" this clock. This default code assumes
+ * that the CM_IDLEST bit shift is the CM_*CLKEN bit shift, and that
+ * the IDLEST register address ID corresponds to the CM_*CLKEN
+ * register address ID (e.g., that CM_FCLKEN2 corresponds to
+ * CM_IDLEST2). This is not true for all modules. No return value.
+ */
+void omap2_clk_dflt_find_idlest(struct clk_hw_omap *clk,
+ void __iomem **idlest_reg, u8 *idlest_bit,
+ u8 *idlest_val)
+{
+ u32 r;
+
+ r = (((__force u32)clk->enable_reg & ~0xf0) | 0x20);
+ *idlest_reg = (__force void __iomem *)r;
+ *idlest_bit = clk->enable_bit;
+
+ /*
+ * 24xx uses 0 to indicate not ready, and 1 to indicate ready.
+ * 34xx reverses this, just to keep us on our toes
+ * AM35xx uses both, depending on the module.
+ */
+ *idlest_val = ti_clk_get_features()->cm_idlest_val;
+}
+
+/**
+ * omap2_dflt_clk_enable - enable a clock in the hardware
+ * @hw: struct clk_hw * of the clock to enable
+ *
+ * Enable the clock @hw in the hardware. We first call into the OMAP
+ * clockdomain code to "enable" the corresponding clockdomain if this
+ * is the first enabled user of the clockdomain. Then program the
+ * hardware to enable the clock. Then wait for the IP block that uses
+ * this clock to leave idle (if applicable). Returns the error value
+ * from clkdm_clk_enable() if it terminated with an error, or -EINVAL
+ * if @hw has a null clock enable_reg, or zero upon success.
+ */
+int omap2_dflt_clk_enable(struct clk_hw *hw)
+{
+ struct clk_hw_omap *clk;
+ u32 v;
+ int ret = 0;
+ bool clkdm_control;
+
+ if (ti_clk_get_features()->flags & TI_CLK_DISABLE_CLKDM_CONTROL)
+ clkdm_control = false;
+ else
+ clkdm_control = true;
+
+ clk = to_clk_hw_omap(hw);
+
+ if (clkdm_control && clk->clkdm) {
+ ret = ti_clk_ll_ops->clkdm_clk_enable(clk->clkdm, hw->clk);
+ if (ret) {
+ WARN(1,
+ "%s: could not enable %s's clockdomain %s: %d\n",
+ __func__, clk_hw_get_name(hw),
+ clk->clkdm_name, ret);
+ return ret;
+ }
+ }
+
+ if (unlikely(!clk->enable_reg)) {
+ pr_err("%s: %s missing enable_reg\n", __func__,
+ clk_hw_get_name(hw));
+ ret = -EINVAL;
+ goto err;
+ }
+
+ /* FIXME should not have INVERT_ENABLE bit here */
+ v = ti_clk_ll_ops->clk_readl(clk->enable_reg);
+ if (clk->flags & INVERT_ENABLE)
+ v &= ~(1 << clk->enable_bit);
+ else
+ v |= (1 << clk->enable_bit);
+ ti_clk_ll_ops->clk_writel(v, clk->enable_reg);
+ v = ti_clk_ll_ops->clk_readl(clk->enable_reg); /* OCP barrier */
+
+ if (clk->ops && clk->ops->find_idlest)
+ _omap2_module_wait_ready(clk);
+
+ return 0;
+
+err:
+ if (clkdm_control && clk->clkdm)
+ ti_clk_ll_ops->clkdm_clk_disable(clk->clkdm, hw->clk);
+ return ret;
+}
+
+/**
+ * omap2_dflt_clk_disable - disable a clock in the hardware
+ * @hw: struct clk_hw * of the clock to disable
+ *
+ * Disable the clock @hw in the hardware, and call into the OMAP
+ * clockdomain code to "disable" the corresponding clockdomain if all
+ * clocks/hwmods in that clockdomain are now disabled. No return
+ * value.
+ */
+void omap2_dflt_clk_disable(struct clk_hw *hw)
+{
+ struct clk_hw_omap *clk;
+ u32 v;
+
+ clk = to_clk_hw_omap(hw);
+ if (!clk->enable_reg) {
+ /*
+ * 'independent' here refers to a clock which is not
+ * controlled by its parent.
+ */
+ pr_err("%s: independent clock %s has no enable_reg\n",
+ __func__, clk_hw_get_name(hw));
+ return;
+ }
+
+ v = ti_clk_ll_ops->clk_readl(clk->enable_reg);
+ if (clk->flags & INVERT_ENABLE)
+ v |= (1 << clk->enable_bit);
+ else
+ v &= ~(1 << clk->enable_bit);
+ ti_clk_ll_ops->clk_writel(v, clk->enable_reg);
+ /* No OCP barrier needed here since it is a disable operation */
+
+ if (!(ti_clk_get_features()->flags & TI_CLK_DISABLE_CLKDM_CONTROL) &&
+ clk->clkdm)
+ ti_clk_ll_ops->clkdm_clk_disable(clk->clkdm, hw->clk);
+}
+
+/**
+ * omap2_dflt_clk_is_enabled - is clock enabled in the hardware?
+ * @hw: struct clk_hw * to check
+ *
+ * Return 1 if the clock represented by @hw is enabled in the
+ * hardware, or 0 otherwise. Intended for use in the struct
+ * clk_ops.is_enabled function pointer.
+ */
+int omap2_dflt_clk_is_enabled(struct clk_hw *hw)
+{
+ struct clk_hw_omap *clk = to_clk_hw_omap(hw);
+ u32 v;
+
+ v = ti_clk_ll_ops->clk_readl(clk->enable_reg);
+
+ if (clk->flags & INVERT_ENABLE)
+ v ^= BIT(clk->enable_bit);
+
+ v &= BIT(clk->enable_bit);
+
+ return v ? 1 : 0;
+}
+
+const struct clk_hw_omap_ops clkhwops_wait = {
+ .find_idlest = omap2_clk_dflt_find_idlest,
+ .find_companion = omap2_clk_dflt_find_companion,
+};