This is the driver for the Power Sleep Controller (PSC) hardware
found on DM SoCs as well Keystone SoCs (c6x). This driver borrowed
code from arch/arm/mach-davinci/psc.c and implemented the driver
as per common clock provider API. The PSC module is responsible for
enabling/disabling the Power Domain and Clock domain for different IPs
present in the SoC. The driver is configured through the platform
data structure struct clk_davinci_psc_data.
Signed-off-by: Murali Karicheri <m-kariche...@ti.com>
diff --git a/drivers/clk/davinci/clk-davinci-psc.c
b/drivers/clk/davinci/clk-davinci-psc.c
new file mode 100644
index 0000000..b7aa332
--- /dev/null
+++ b/drivers/clk/davinci/clk-davinci-psc.c
@@ -0,0 +1,197 @@
+/*
+ * PSC clk driver for DaVinci devices
+ *
+ * Copyright (C) 2006-2012 Texas Instruments.
+ * Copyright (C) 2008-2009 Deep Root Systems, LLC
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/platform_data/clk-davinci-psc.h>
+
+/* PSC register offsets */
+#define EPCPR 0x070
+#define PTCMD 0x120
+#define PTSTAT 0x128
+#define PDSTAT 0x200
+#define PDCTL 0x300
+#define MDSTAT 0x800
+#define MDCTL 0xA00
+
+/* PSC module states */
+#define PSC_STATE_SWRSTDISABLE 0
+#define PSC_STATE_SYNCRST 1
+#define PSC_STATE_DISABLE 2
+#define PSC_STATE_ENABLE 3
+
+#define MDSTAT_STATE_MASK 0x3f
+#define PDSTAT_STATE_MASK 0x1f
+#define MDCTL_FORCE BIT(31)
+#define PDCTL_NEXT BIT(0)
+#define PDCTL_EPCGOOD BIT(8)
+
+/* PSC flags */
+#define PSC_SWRSTDISABLE BIT(0) /* Disable state is SwRstDisable */
+#define PSC_FORCE BIT(1) /* Force module state transtition */
+#define PSC_HAS_EXT_POWER_CNTL BIT(2) /* PSC has external power control
+ * available (for DM6446 SoC) */
+/**
+ * struct clk_psc - DaVinci PSC clock
+ * @hw: clk_hw for the psc
+ * @psc_data: PSC driver specific data
+ * @lock: Spinlock used by the driver
+ */
+struct clk_psc {
+ struct clk_hw hw;
+ struct clk_davinci_psc_data *psc_data;
+ spinlock_t *lock;
+};
+
+#define to_clk_psc(_hw) container_of(_hw, struct clk_psc, hw)
+
+/* Enable or disable a PSC domain */
+static void clk_psc_config(void __iomem *base, unsigned int domain,
+ unsigned int id, bool enable, u32 flags)
+{
+ u32 epcpr, ptcmd, ptstat, pdstat, pdctl, mdstat, mdctl;
+ u32 next_state = PSC_STATE_ENABLE;
+ void __iomem *psc_base = base;
+
+ if (!enable) {
+ if (flags & PSC_SWRSTDISABLE)
+ next_state = PSC_STATE_SWRSTDISABLE;
+ else
+ next_state = PSC_STATE_DISABLE;
+ }
+
+ mdctl = __raw_readl(psc_base + MDCTL + 4 * id);
+ mdctl &= ~MDSTAT_STATE_MASK;
+ mdctl |= next_state;
+ if (flags & PSC_FORCE)
+ mdctl |= MDCTL_FORCE;
+ __raw_writel(mdctl, psc_base + MDCTL + 4 * id);
+
+ pdstat = __raw_readl(psc_base + PDSTAT + 4 * domain);
+ if ((pdstat & PDSTAT_STATE_MASK) == 0) {
+ pdctl = __raw_readl(psc_base + PDCTL + 4 * domain);
+ pdctl |= PDCTL_NEXT;
+ __raw_writel(pdctl, psc_base + PDCTL + 4 * domain);
+
+ ptcmd = 1 << domain;
+ __raw_writel(ptcmd, psc_base + PTCMD);
+
+ if (flags & PSC_HAS_EXT_POWER_CNTL) {
+ do {
+ epcpr = __raw_readl(psc_base + EPCPR);
+ } while ((((epcpr >> domain) & 1) == 0));
+ }
+
+ pdctl = __raw_readl(psc_base + PDCTL + 4 * domain);
+ pdctl |= 0x100;
+ __raw_writel(pdctl, psc_base + PDCTL + 4 * domain);
+
+ pdctl = __raw_readl(psc_base + PDCTL + 4 * domain);
+ pdctl |= PDCTL_EPCGOOD;
+ __raw_writel(pdctl, psc_base + PDCTL + 4 * domain);
+ } else {
+ ptcmd = 1 << domain;
+ __raw_writel(ptcmd, psc_base + PTCMD);
+ }
+
+ do {
+ ptstat = __raw_readl(psc_base + PTSTAT);
+ } while (!(((ptstat >> domain) & 1) == 0));
+
+ do {
+ mdstat = __raw_readl(psc_base + MDSTAT + 4 * id);
+ } while (!((mdstat & MDSTAT_STATE_MASK) == next_state));
+}
+
+static int clk_psc_is_enabled(struct clk_hw *hw)
+{
+ struct clk_psc *psc = to_clk_psc(hw);
+ struct clk_davinci_psc_data *psc_data = psc->psc_data;
+ u32 mdstat;
+
+ mdstat = __raw_readl(psc_data->base + MDSTAT + 4 * psc_data->lpsc);
+ /* if clocked, state can be "Enable" or "SyncReset" */
+ return (mdstat & BIT(12)) ? 1 : 0;
+}
+
+static int clk_psc_enable(struct clk_hw *hw)
+{
+ struct clk_psc *psc = to_clk_psc(hw);
+ struct clk_davinci_psc_data *psc_data = psc->psc_data;
+ unsigned long flags = 0;
+
+ if (psc->lock)
+ spin_lock_irqsave(psc->lock, flags);
+
+ clk_psc_config(psc_data->base, psc_data->domain, psc_data->lpsc,
+ 1, psc_data->psc_flags);
+
+ if (psc->lock)
+ spin_unlock_irqrestore(psc->lock, flags);
+
+ return 0;
+}
+
+static void clk_psc_disable(struct clk_hw *hw)
+{
+ struct clk_psc *psc = to_clk_psc(hw);
+ struct clk_davinci_psc_data *psc_data = psc->psc_data;
+ unsigned long flags = 0;
+
+ if (psc->lock)
+ spin_lock_irqsave(psc->lock, flags);
+
+ clk_psc_config(psc_data->base, psc_data->domain, psc_data->lpsc,
+ 0, psc_data->psc_flags);
+
+ if (psc->lock)
+ spin_unlock_irqrestore(psc->lock, flags);
+}
+
+static const struct clk_ops clk_psc_ops = {
+ .enable = clk_psc_enable,
+ .disable = clk_psc_disable,
+ .is_enabled = clk_psc_is_enabled,
+};
+
+struct clk *clk_register_davinci_psc(struct device *dev, const char *name,
+ const char *parent_name,
+ struct clk_davinci_psc_data *psc_data,
+ spinlock_t *lock)
+{
+ struct clk_init_data init;
+ struct clk_psc *psc;
+ struct clk *clk;
+
+ psc = kzalloc(sizeof(*psc), GFP_KERNEL);
+ if (!psc)
+ return ERR_PTR(-ENOMEM);
+
+ init.name = name;
+ init.ops = &clk_psc_ops;
+ init.flags = psc_data->flags;
+ init.parent_names = (parent_name ? &parent_name : NULL);
+ init.num_parents = (parent_name ? 1 : 0);
+
+ psc->psc_data = psc_data;
+ psc->lock = lock;
+ psc->hw.init = &init;
+
+ clk = clk_register(NULL, &psc->hw);
+ if (IS_ERR(clk))
+ kfree(psc);
+
+ return clk;
+}
diff --git a/include/linux/platform_data/clk-davinci-psc.h
b/include/linux/platform_data/clk-davinci-psc.h
new file mode 100644
index 0000000..b805f72
--- /dev/null
+++ b/include/linux/platform_data/clk-davinci-psc.h
@@ -0,0 +1,53 @@
+/*
+ * DaVinci Power & Sleep Controller (PSC) clk driver platform data
+ *
+ * Copyright (C) 2006-2012 Texas Instruments.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
+ * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ */
+#ifndef __CLK_DAVINCI_PSC_H
+#define __CLK_DAVINCI_PSC_H
+
+/* PSC flags */
+/* Disable state is SwRstDisable */
+#define CLK_DAVINCI_PSC_SWRSTDISABLE BIT(0)
+/* Force module state transtition */
+#define CLK_DAVINCI_PSC_FORCE BIT(1)
+/* PSC has external power control available (for DM6446 SoC) */
+#define CLK_DAVINCI_PSC_HAS_EXT_POWER_CNTL BIT(2)
+struct clk_davinci_psc_data {
+ /* base address of the PSC */
+ void __iomem *base;
+ /* framework flags */
+ u32 flags;
+ /* psc specific flags */
+ u32 psc_flags;
+ u8 lpsc;
+ u8 gpsc;
+ u8 domain;
+};
+
+extern struct clk *clk_register_davinci_psc(struct device *dev,
+ const char *name, const char *parent_name,
+ struct clk_davinci_psc_data *psc_data,
+ spinlock_t *lock);
+#endif /* __CLK_DAVINCI_PSC_H */
--
1.7.9.5
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