[PATCHv5] omap3: Add basic support for 720MHz part

[Sanjeev Premi <premi@ti.com>]

This patch adds support for speed enhanced variant of OMAP35x
processors. These parts allow ARM and IVA running at 720MHz
and 520MHz respectively.

These parts can be detected at runtime by reading contents of
PRODID.SKUID[3:0] at 0x4830A20C [1].

This patch specifically does following:
 * Add new OPP to omap34xx_opp_def_list[] - disabled by default.
 * Detect devices capable of running at new OPP.
 * Enable new OPP only if device supports it.
 * Check for presence of IVA before attempting to enable the
   corresponding OPP.

  [1] http://focus.ti.com/lit/ug/spruff1d/spruff1d.pdf

It appears from discussions (on this patch) that a variant of
OMAP3430 supports this OPP but lacks runtime detection. This
OPP can be enabled for these device by either:
 1) Setting the bit corresponding to OMAP3_HAS_720MHZ
    in 'omap3_features'. (Refer changes to id.c)
 2) Removing check for omap3_has_720mhz() before enabling
    the OPP. (Refer changes to opp3xxx_data.c)
 3) Calling opp_enable() for 720MHz/VDD1 and 520MHz/VDD2 in
    the board file. (Refer changes to opp3xxx_data.c).
    This should, ideally, be done before omap3_opp_init() is
    called during device_initcall().

CAUTION: This should be done for identified parts only.
         Else, the device could be damaged permanently.

Signed-off-by: Sanjeev Premi <premi@ti.com>
Reviewed-by: G, Manjunath Kondaiah <manjugk@ti.com>
---

Since v4:
  Updated the commit text addressing comments from
  Kevin Hilman (khilman@ti.com).

Since v3:
1) Minor changes to comments and braces.
   
Since v2:
1) pr_xxx() -> dev_xxx() functions - suggested by 
   Manjunath (manjugk@ti.com)
2) Add check for presense of IVA - earlier planned to
   be in a separate patch; but we multiple discussions
   on optimizations.
3) Do look-up for hwmod corresponding for iva only if
   iva is present. Should save multiple strcmp()s in
   _lookup().

Since v1:
1) Using opp_enable() to enable the OPP after the OPP
   table has been initialized.
2) Starting at 3 levels of indent, the statements had
   be broken into multiple lines for most of the code.
   So, opted to create a new static that enables the
   OPPs corresponding to 720MHz.
3) I have only build tested this patch - will be able
   to confirm working tomorrow. With any further change,
   if needed. (However, functionally nothing has changed.)


 arch/arm/mach-omap2/control.h         |    6 +++
 arch/arm/mach-omap2/id.c              |    5 +++
 arch/arm/mach-omap2/opp3xxx_data.c    |   63 ++++++++++++++++++++++++++++++++-
 arch/arm/plat-omap/include/plat/cpu.h |    2 +
 4 files changed, 75 insertions(+), 1 deletions(-)

diff --git a/arch/arm/mach-omap2/control.h b/arch/arm/mach-omap2/control.h
index f0629ae..c338466 100644
--- a/arch/arm/mach-omap2/control.h
+++ b/arch/arm/mach-omap2/control.h
@@ -365,6 +365,12 @@
 #define		FEAT_NEON		0
 #define		FEAT_NEON_NONE		1
 
+/* Product ID register */
+#define OMAP3_PRODID			0x020C
+
+/* Mask to extract SKU ID from Product ID */
+#define OMAP3_SKUID_MASK		0x0f
+#define		OMAP3_SKUID_720MHZ	0x08
 
 #ifndef __ASSEMBLY__
 #ifdef CONFIG_ARCH_OMAP2PLUS
diff --git a/arch/arm/mach-omap2/id.c b/arch/arm/mach-omap2/id.c
index 5f9086c..8c4500f 100644
--- a/arch/arm/mach-omap2/id.c
+++ b/arch/arm/mach-omap2/id.c
@@ -191,6 +191,10 @@ static void __init omap3_check_features(void)
 	if (!cpu_is_omap3505() && !cpu_is_omap3517())
 		omap3_features |= OMAP3_HAS_IO_WAKEUP;
 
+	status = (OMAP3_SKUID_MASK & read_tap_reg(OMAP3_PRODID));
+	if (status & OMAP3_SKUID_720MHZ)
+		omap3_features |= OMAP3_HAS_720MHZ;
+
 	/*
 	 * TODO: Get additional info (where applicable)
 	 *       e.g. Size of L2 cache.
@@ -445,6 +449,7 @@ static void __init omap3_cpuinfo(void)
 	OMAP3_SHOW_FEATURE(neon);
 	OMAP3_SHOW_FEATURE(isp);
 	OMAP3_SHOW_FEATURE(192mhz_clk);
+	OMAP3_SHOW_FEATURE(720mhz);
 
 	printk(")\n");
 }
diff --git a/arch/arm/mach-omap2/opp3xxx_data.c b/arch/arm/mach-omap2/opp3xxx_data.c
index 0486fce..cba17f7 100644
--- a/arch/arm/mach-omap2/opp3xxx_data.c
+++ b/arch/arm/mach-omap2/opp3xxx_data.c
@@ -17,8 +17,10 @@
  * GNU General Public License for more details.
  */
 #include <linux/module.h>
+#include <linux/opp.h>
 
 #include <plat/cpu.h>
+#include <plat/omap_device.h>
 
 #include "omap_opp_data.h"
 
@@ -33,6 +35,8 @@ static struct omap_opp_def __initdata omap34xx_opp_def_list[] = {
 	OPP_INITIALIZER("mpu", true, 550000000, 1270000),
 	/* MPU OPP5 */
 	OPP_INITIALIZER("mpu", true, 600000000, 1350000),
+	/* MPU OPP6 */
+	OPP_INITIALIZER("mpu", false, 720000000, 1350000),
 
 	/*
 	 * L3 OPP1 - 41.5 MHz is disabled because: The voltage for that OPP is
@@ -58,6 +62,8 @@ static struct omap_opp_def __initdata omap34xx_opp_def_list[] = {
 	OPP_INITIALIZER("iva", true, 400000000, 1270000),
 	/* DSP OPP5 */
 	OPP_INITIALIZER("iva", true, 430000000, 1350000),
+	/* DSP OPP6 */
+	OPP_INITIALIZER("iva", false, 520000000, 1350000),
 };
 
 static struct omap_opp_def __initdata omap36xx_opp_def_list[] = {
@@ -85,6 +91,57 @@ static struct omap_opp_def __initdata omap36xx_opp_def_list[] = {
 	OPP_INITIALIZER("iva", false, 800000000, 1375000),
 };
 
+
+/**
+ * omap3_opp_enable_720Mhz() - Enable the OPP corresponding to 720MHz
+ *
+ * This function would be executed only if the silicon is capable of
+ * running at the 720MHz.
+ */
+static int __init omap3_opp_enable_720Mhz(void)
+{
+	int r = -ENODEV;
+	struct omap_hwmod *oh_mpu = omap_hwmod_lookup("mpu");
+	struct omap_hwmod *oh_iva;
+	struct platform_device *pdev;
+
+	if (!oh_mpu || !oh_mpu->od) {
+		goto err;
+	} else {
+		pdev = &oh_mpu->od->pdev;
+
+		r = opp_enable(&pdev->dev, 720000000);
+		if (r < 0) {
+			dev_err(&pdev->dev,
+				"opp_enable() failed for mpu@720MHz");
+			goto err;
+		}
+	}
+
+	if (omap3_has_iva()) {
+		oh_iva = omap_hwmod_lookup("iva");
+
+		if (!oh_iva || !oh_iva->od) {
+			r = -ENODEV;
+			goto err;
+		} else {
+			pdev = &oh_iva->od->pdev;
+
+			r = opp_enable(&pdev->dev, 520000000);
+			if (r < 0) {
+				dev_err(&pdev->dev,
+					"opp_enable() failed for iva@520MHz");
+				goto err;
+			}
+		}
+	}
+
+	dev_info(&pdev->dev, "Enabled OPP corresponding to 720MHz\n");
+
+err:
+	return r;
+}
+
 /**
  * omap3_opp_init() - initialize omap3 opp table
  */
@@ -98,10 +155,14 @@ static int __init omap3_opp_init(void)
 	if (cpu_is_omap3630())
 		r = omap_init_opp_table(omap36xx_opp_def_list,
 			ARRAY_SIZE(omap36xx_opp_def_list));
-	else
+	else {
 		r = omap_init_opp_table(omap34xx_opp_def_list,
 			ARRAY_SIZE(omap34xx_opp_def_list));
 
+		if (omap3_has_720mhz())
+			r = omap3_opp_enable_720Mhz();
+	}
+
 	return r;
 }
 device_initcall(omap3_opp_init);
diff --git a/arch/arm/plat-omap/include/plat/cpu.h b/arch/arm/plat-omap/include/plat/cpu.h
index 73d91ee..e624ee1 100644
--- a/arch/arm/plat-omap/include/plat/cpu.h
+++ b/arch/arm/plat-omap/include/plat/cpu.h
@@ -455,6 +455,7 @@ extern u32 omap3_features;
 #define OMAP3_HAS_ISP			BIT(4)
 #define OMAP3_HAS_192MHZ_CLK		BIT(5)
 #define OMAP3_HAS_IO_WAKEUP		BIT(6)
+#define OMAP3_HAS_720MHZ		BIT(7)
 
 #define OMAP3_HAS_FEATURE(feat,flag)			\
 static inline unsigned int omap3_has_ ##feat(void)	\
@@ -469,5 +470,6 @@ OMAP3_HAS_FEATURE(neon, NEON)
 OMAP3_HAS_FEATURE(isp, ISP)
 OMAP3_HAS_FEATURE(192mhz_clk, 192MHZ_CLK)
 OMAP3_HAS_FEATURE(io_wakeup, IO_WAKEUP)
+OMAP3_HAS_FEATURE(720mhz, 720MHZ)
 
 #endif
-- 
1.7.2.2