OMAP2/3 PM: create the OMAP PM interface and add a default OMAP PM no-op layer

The interface provides device drivers, CPUFreq, and DSPBridge with a
means of controlling OMAP power management parameters that are not yet
supported by the Linux PM PMQoS interface.  Copious documentation is
in the patch in Documentation/arm/OMAP/omap_pm and the interface
header file, arch/arm/plat-omap/include/mach/omap-pm.h.

Thanks to Rajendra Nayak <rnayak@ti.com> for adding CORE (VDD2) OPP
support and moving the OPP table initialization earlier in the event
that the clock code needs them.  Thanks to Tero Kristo
<tero.kristo@nokia.com> for fixing the parameter check in
omap_pm_set_min_bus_tput().  Jouni signed off on Tero's patch.

Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: Rajendra Nayak <rnayak@ti.com>
Signed-off-by: Tero Kristo <tero.kristo@nokia.com>
Signed-off-by: Jouni Högander <jouni.hogander@nokia.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Igor Stoppa <igor.stoppa@nokia.com>
Cc: Richard Woodruff <r-woodruff2@ti.com>
Cc: Anand Sawant <sawant@ti.com>
Cc: Sakari Poussa <sakari.poussa@nokia.com>
Cc: Veeramanikandan Raju <veera@ti.com>
Cc: Karthik Dasu <karthik-dp@ti.com>

1 files changed, 296 insertions, 0 deletions

diff --git a/arch/arm/plat-omap/omap-pm-noop.c b/arch/arm/plat-omap/omap-pm-noop.c
new file mode 100644
index 0000000..e98f0a2
--- /dev/null
+++ b/arch/arm/plat-omap/omap-pm-noop.c
@@ -0,0 +1,296 @@
+/*
+ * omap-pm-noop.c - OMAP power management interface - dummy version
+ *
+ * This code implements the OMAP power management interface to
+ * drivers, CPUIdle, CPUFreq, and DSP Bridge.  It is strictly for
+ * debug/demonstration use, as it does nothing but printk() whenever a
+ * function is called (when DEBUG is defined, below)
+ *
+ * Copyright (C) 2008-2009 Texas Instruments, Inc.
+ * Copyright (C) 2008-2009 Nokia Corporation
+ * Paul Walmsley
+ *
+ * Interface developed by (in alphabetical order):
+ * Karthik Dasu, Tony Lindgren, Rajendra Nayak, Sakari Poussa, Veeramanikandan
+ * Raju, Anand Sawant, Igor Stoppa, Paul Walmsley, Richard Woodruff
+ */
+
+#undef DEBUG
+
+#include <linux/init.h>
+#include <linux/cpufreq.h>
+#include <linux/device.h>
+
+/* Interface documentation is in mach/omap-pm.h */
+#include <mach/omap-pm.h>
+
+#include <mach/powerdomain.h>
+
+struct omap_opp *dsp_opps;
+struct omap_opp *mpu_opps;
+struct omap_opp *l3_opps;
+
+/*
+ * Device-driver-originated constraints (via board-*.c files)
+ */
+
+void omap_pm_set_max_mpu_wakeup_lat(struct device *dev, long t)
+{
+	if (!dev || t < -1) {
+		WARN_ON(1);
+		return;
+	};
+
+	if (t == -1)
+		pr_debug("OMAP PM: remove max MPU wakeup latency constraint: "
+			 "dev %s\n", dev_name(dev));
+	else
+		pr_debug("OMAP PM: add max MPU wakeup latency constraint: "
+			 "dev %s, t = %ld usec\n", dev_name(dev), t);
+
+	/*
+	 * For current Linux, this needs to map the MPU to a
+	 * powerdomain, then go through the list of current max lat
+	 * constraints on the MPU and find the smallest.  If
+	 * the latency constraint has changed, the code should
+	 * recompute the state to enter for the next powerdomain
+	 * state.
+	 *
+	 * TI CDP code can call constraint_set here.
+	 */
+}
+
+void omap_pm_set_min_bus_tput(struct device *dev, u8 agent_id, unsigned long r)
+{
+	if (!dev || (agent_id != OCP_INITIATOR_AGENT &&
+	    agent_id != OCP_TARGET_AGENT)) {
+		WARN_ON(1);
+		return;
+	};
+
+	if (r == 0)
+		pr_debug("OMAP PM: remove min bus tput constraint: "
+			 "dev %s for agent_id %d\n", dev_name(dev), agent_id);
+	else
+		pr_debug("OMAP PM: add min bus tput constraint: "
+			 "dev %s for agent_id %d: rate %ld KiB\n",
+			 dev_name(dev), agent_id, r);
+
+	/*
+	 * This code should model the interconnect and compute the
+	 * required clock frequency, convert that to a VDD2 OPP ID, then
+	 * set the VDD2 OPP appropriately.
+	 *
+	 * TI CDP code can call constraint_set here on the VDD2 OPP.
+	 */
+}
+
+void omap_pm_set_max_dev_wakeup_lat(struct device *dev, long t)
+{
+	if (!dev || t < -1) {
+		WARN_ON(1);
+		return;
+	};
+
+	if (t == -1)
+		pr_debug("OMAP PM: remove max device latency constraint: "
+			 "dev %s\n", dev_name(dev));
+	else
+		pr_debug("OMAP PM: add max device latency constraint: "
+			 "dev %s, t = %ld usec\n", dev_name(dev), t);
+
+	/*
+	 * For current Linux, this needs to map the device to a
+	 * powerdomain, then go through the list of current max lat
+	 * constraints on that powerdomain and find the smallest.  If
+	 * the latency constraint has changed, the code should
+	 * recompute the state to enter for the next powerdomain
+	 * state.  Conceivably, this code should also determine
+	 * whether to actually disable the device clocks or not,
+	 * depending on how long it takes to re-enable the clocks.
+	 *
+	 * TI CDP code can call constraint_set here.
+	 */
+}
+
+void omap_pm_set_max_sdma_lat(struct device *dev, long t)
+{
+	if (!dev || t < -1) {
+		WARN_ON(1);
+		return;
+	};
+
+	if (t == -1)
+		pr_debug("OMAP PM: remove max DMA latency constraint: "
+			 "dev %s\n", dev_name(dev));
+	else
+		pr_debug("OMAP PM: add max DMA latency constraint: "
+			 "dev %s, t = %ld usec\n", dev_name(dev), t);
+
+	/*
+	 * For current Linux PM QOS params, this code should scan the
+	 * list of maximum CPU and DMA latencies and select the
+	 * smallest, then set cpu_dma_latency pm_qos_param
+	 * accordingly.
+	 *
+	 * For future Linux PM QOS params, with separate CPU and DMA
+	 * latency params, this code should just set the dma_latency param.
+	 *
+	 * TI CDP code can call constraint_set here.
+	 */
+
+}
+
+
+/*
+ * DSP Bridge-specific constraints
+ */
+
+const struct omap_opp *omap_pm_dsp_get_opp_table(void)
+{
+	pr_debug("OMAP PM: DSP request for OPP table\n");
+
+	/*
+	 * Return DSP frequency table here:  The final item in the
+	 * array should have .rate = .opp_id = 0.
+	 */
+
+	return NULL;
+}
+
+void omap_pm_dsp_set_min_opp(u8 opp_id)
+{
+	if (opp_id == 0) {
+		WARN_ON(1);
+		return;
+	}
+
+	pr_debug("OMAP PM: DSP requests minimum VDD1 OPP to be %d\n", opp_id);
+
+	/*
+	 *
+	 * For l-o dev tree, our VDD1 clk is keyed on OPP ID, so we
+	 * can just test to see which is higher, the CPU's desired OPP
+	 * ID or the DSP's desired OPP ID, and use whichever is
+	 * highest.
+	 *
+	 * In CDP12.14+, the VDD1 OPP custom clock that controls the DSP
+	 * rate is keyed on MPU speed, not the OPP ID.  So we need to
+	 * map the OPP ID to the MPU speed for use with clk_set_rate()
+	 * if it is higher than the current OPP clock rate.
+	 *
+	 */
+}
+
+
+u8 omap_pm_dsp_get_opp(void)
+{
+	pr_debug("OMAP PM: DSP requests current DSP OPP ID\n");
+
+	/*
+	 * For l-o dev tree, call clk_get_rate() on VDD1 OPP clock
+	 *
+	 * CDP12.14+:
+	 * Call clk_get_rate() on the OPP custom clock, map that to an
+	 * OPP ID using the tables defined in board-*.c/chip-*.c files.
+	 */
+
+	return 0;
+}
+
+/*
+ * CPUFreq-originated constraint
+ *
+ * In the future, this should be handled by custom OPP clocktype
+ * functions.
+ */
+
+struct cpufreq_frequency_table **omap_pm_cpu_get_freq_table(void)
+{
+	pr_debug("OMAP PM: CPUFreq request for frequency table\n");
+
+	/*
+	 * Return CPUFreq frequency table here: loop over
+	 * all VDD1 clkrates, pull out the mpu_ck frequencies, build
+	 * table
+	 */
+
+	return NULL;
+}
+
+void omap_pm_cpu_set_freq(unsigned long f)
+{
+	if (f == 0) {
+		WARN_ON(1);
+		return;
+	}
+
+	pr_debug("OMAP PM: CPUFreq requests CPU frequency to be set to %lu\n",
+		 f);
+
+	/*
+	 * For l-o dev tree, determine whether MPU freq or DSP OPP id
+	 * freq is higher.  Find the OPP ID corresponding to the
+	 * higher frequency.  Call clk_round_rate() and clk_set_rate()
+	 * on the OPP custom clock.
+	 *
+	 * CDP should just be able to set the VDD1 OPP clock rate here.
+	 */
+}
+
+unsigned long omap_pm_cpu_get_freq(void)
+{
+	pr_debug("OMAP PM: CPUFreq requests current CPU frequency\n");
+
+	/*
+	 * Call clk_get_rate() on the mpu_ck.
+	 */
+
+	return 0;
+}
+
+/*
+ * Device context loss tracking
+ */
+
+int omap_pm_get_dev_context_loss_count(struct device *dev)
+{
+	if (!dev) {
+		WARN_ON(1);
+		return -EINVAL;
+	};
+
+	pr_debug("OMAP PM: returning context loss count for dev %s\n",
+		 dev_name(dev));
+
+	/*
+	 * Map the device to the powerdomain.  Return the powerdomain
+	 * off counter.
+	 */
+
+	return 0;
+}
+
+
+/* Should be called before clk framework init */
+int __init omap_pm_if_early_init(struct omap_opp *mpu_opp_table,
+				 struct omap_opp *dsp_opp_table,
+				 struct omap_opp *l3_opp_table)
+{
+	mpu_opps = mpu_opp_table;
+	dsp_opps = dsp_opp_table;
+	l3_opps = l3_opp_table;
+	return 0;
+}
+
+/* Must be called after clock framework is initialized */
+int __init omap_pm_if_init(void)
+{
+	return 0;
+}
+
+void omap_pm_if_exit(void)
+{
+	/* Deallocate CPUFreq frequency table here */
+}
+