ARM: OMAP2+: AM335x: Handle OPP50 Bootup

As per Advisory 1.0.15 (ARM Cortex-A8: OPP50 Operation on MPU Domain Not Supported), when the board is booted with OPP50, reliable operation is not guaranteed for OPP greater than OPP100 (OPP120, TURBO, NITRO). So, Check if the board is booted at OPP50 voltage & if yes, disable higher OPP (OPP120, TURBO, NITRO). Signed-off-by: Hebbar Gururaja <gururaja.hebbar@ti.com>

ARM: OMAP2+: AM335x: Handle OPP50 Bootup
As per Advisory 1.0.15 (ARM Cortex-A8: OPP50 Operation on MPU Domain Not Supported), when the board is booted with OPP50, reliable operation is not guaranteed for OPP greater than OPP100 (OPP120, TURBO, NITRO). So, Check if the board is booted at OPP50 voltage & if yes, disable higher OPP (OPP120, TURBO, NITRO). Signed-off-by: Hebbar Gururaja <gururaja.hebbar@ti.com>
Hebbar Gururaja
1 parent ee9dfd8d72
Showing 1 changed file with 92 additions and 0 deletions Side-by-side Diff
arch/arm/mach-omap2/board-am335xevm.c
@@ -2181,6 +2181,96 @@
 	return 0;
 }
  
+#define AM33XX_VDD_MPU_OPP50_UV		1100000
+#define AM33XX_OPP120_FREQ		600000000
+#define AM33XX_OPPTURBO_FREQ		720000000
+
+#define AM33XX_ES2_0_VDD_MPU_OPP50_UV	950000
+#define AM33XX_ES2_0_OPPTURBO_FREQ	800000000
+#define AM33XX_ES2_0_OPPNITRO_FREQ	1000000000
+
+#define AM33XX_ES2_1_VDD_MPU_OPP50_UV	950000
+#define AM33XX_ES2_1_OPPTURBO_FREQ	800000000
+#define AM33XX_ES2_1_OPPNITRO_FREQ	1000000000
+
+static void am335x_opp_update(void)
+{
+	u32 rev;
+	int voltage_uv = 0;
+	struct device *core_dev, *mpu_dev;
+	struct regulator *core_reg;
+
+	core_dev = omap_device_get_by_hwmod_name("l3_main");
+	mpu_dev = omap_device_get_by_hwmod_name("mpu");
+
+	if (!mpu_dev || !core_dev) {
+		pr_err("%s: Aiee.. no mpu/core devices? %p %p\n", __func__,
+		       mpu_dev, core_dev);
+		return;
+	}
+
+	core_reg = regulator_get(core_dev, "vdd_core");
+	if (IS_ERR(core_reg)) {
+		pr_err("%s: unable to get core regulator\n", __func__);
+		return;
+	}
+
+	/*
+	 * Ensure physical regulator is present.
+	 * (e.g. could be dummy regulator.)
+	 */
+	voltage_uv = regulator_get_voltage(core_reg);
+	if (voltage_uv < 0) {
+		pr_err("%s: physical regulator not present for core" \
+		       "(%d)\n", __func__, voltage_uv);
+		regulator_put(core_reg);
+		return;
+	}
+
+	pr_debug("%s: core regulator value %d\n", __func__, voltage_uv);
+	if (voltage_uv > 0) {
+		rev = omap_rev();
+		switch (rev) {
+		case AM335X_REV_ES1_0:
+			if (voltage_uv <= AM33XX_VDD_MPU_OPP50_UV) {
+				/*
+				 * disable the higher freqs - we dont care about
+				 * the results
+				 */
+				opp_disable(mpu_dev, AM33XX_OPP120_FREQ);
+				opp_disable(mpu_dev, AM33XX_OPPTURBO_FREQ);
+			}
+			break;
+		case AM335X_REV_ES2_0:
+			if (voltage_uv <= AM33XX_ES2_0_VDD_MPU_OPP50_UV) {
+				/*
+				 * disable the higher freqs - we dont care about
+				 * the results
+				 */
+				opp_disable(mpu_dev,
+					    AM33XX_ES2_0_OPPTURBO_FREQ);
+				opp_disable(mpu_dev,
+					    AM33XX_ES2_0_OPPNITRO_FREQ);
+			}
+			break;
+		case AM335X_REV_ES2_1:
+		/* FALLTHROUGH */
+		default:
+			if (voltage_uv <= AM33XX_ES2_1_VDD_MPU_OPP50_UV) {
+				/*
+				 * disable the higher freqs - we dont care about
+				 * the results
+				 */
+				opp_disable(mpu_dev,
+					    AM33XX_ES2_1_OPPTURBO_FREQ);
+				opp_disable(mpu_dev,
+					    AM33XX_ES2_1_OPPNITRO_FREQ);
+			}
+			break;
+		}
+	}
+}
+
 static void setup_general_purpose_evm(void)
 {
 	u32 prof_sel = am335x_get_profile_selection();
@@ -2361,6 +2451,8 @@
 		else
 			goto out;
 	}
+
+	am335x_opp_update();
  
 	return;
...	...	@@ -2181,6 +2181,96 @@
2181	2181	return 0;
2182	2182	}
2183	2183
	2184	+#define AM33XX_VDD_MPU_OPP50_UV 1100000
	2185	+#define AM33XX_OPP120_FREQ 600000000
	2186	+#define AM33XX_OPPTURBO_FREQ 720000000
	2187	+
	2188	+#define AM33XX_ES2_0_VDD_MPU_OPP50_UV 950000
	2189	+#define AM33XX_ES2_0_OPPTURBO_FREQ 800000000
	2190	+#define AM33XX_ES2_0_OPPNITRO_FREQ 1000000000
	2191	+
	2192	+#define AM33XX_ES2_1_VDD_MPU_OPP50_UV 950000
	2193	+#define AM33XX_ES2_1_OPPTURBO_FREQ 800000000
	2194	+#define AM33XX_ES2_1_OPPNITRO_FREQ 1000000000
	2195	+
	2196	+static void am335x_opp_update(void)
	2197	+{
	2198	+ u32 rev;
	2199	+ int voltage_uv = 0;
	2200	+ struct device core_dev, mpu_dev;
	2201	+ struct regulator *core_reg;
	2202	+
	2203	+ core_dev = omap_device_get_by_hwmod_name("l3_main");
	2204	+ mpu_dev = omap_device_get_by_hwmod_name("mpu");
	2205	+
	2206	+ if (!mpu_dev \|\| !core_dev) {
	2207	+ pr_err("%s: Aiee.. no mpu/core devices? %p %p\n", __func__,
	2208	+ mpu_dev, core_dev);
	2209	+ return;
	2210	+ }
	2211	+
	2212	+ core_reg = regulator_get(core_dev, "vdd_core");
	2213	+ if (IS_ERR(core_reg)) {
	2214	+ pr_err("%s: unable to get core regulator\n", __func__);
	2215	+ return;
	2216	+ }
	2217	+
	2218	+ /*
	2219	+ * Ensure physical regulator is present.
	2220	+ * (e.g. could be dummy regulator.)
	2221	+ */
	2222	+ voltage_uv = regulator_get_voltage(core_reg);
	2223	+ if (voltage_uv < 0) {
	2224	+ pr_err("%s: physical regulator not present for core" \
	2225	+ "(%d)\n", __func__, voltage_uv);
	2226	+ regulator_put(core_reg);
	2227	+ return;
	2228	+ }
	2229	+
	2230	+ pr_debug("%s: core regulator value %d\n", __func__, voltage_uv);
	2231	+ if (voltage_uv > 0) {
	2232	+ rev = omap_rev();
	2233	+ switch (rev) {
	2234	+ case AM335X_REV_ES1_0:
	2235	+ if (voltage_uv <= AM33XX_VDD_MPU_OPP50_UV) {
	2236	+ /*
	2237	+ * disable the higher freqs - we dont care about
	2238	+ * the results
	2239	+ */
	2240	+ opp_disable(mpu_dev, AM33XX_OPP120_FREQ);
	2241	+ opp_disable(mpu_dev, AM33XX_OPPTURBO_FREQ);
	2242	+ }
	2243	+ break;
	2244	+ case AM335X_REV_ES2_0:
	2245	+ if (voltage_uv <= AM33XX_ES2_0_VDD_MPU_OPP50_UV) {
	2246	+ /*
	2247	+ * disable the higher freqs - we dont care about
	2248	+ * the results
	2249	+ */
	2250	+ opp_disable(mpu_dev,
	2251	+ AM33XX_ES2_0_OPPTURBO_FREQ);
	2252	+ opp_disable(mpu_dev,
	2253	+ AM33XX_ES2_0_OPPNITRO_FREQ);
	2254	+ }
	2255	+ break;
	2256	+ case AM335X_REV_ES2_1:
	2257	+ /* FALLTHROUGH */
	2258	+ default:
	2259	+ if (voltage_uv <= AM33XX_ES2_1_VDD_MPU_OPP50_UV) {
	2260	+ /*
	2261	+ * disable the higher freqs - we dont care about
	2262	+ * the results
	2263	+ */
	2264	+ opp_disable(mpu_dev,
	2265	+ AM33XX_ES2_1_OPPTURBO_FREQ);
	2266	+ opp_disable(mpu_dev,
	2267	+ AM33XX_ES2_1_OPPNITRO_FREQ);
	2268	+ }
	2269	+ break;
	2270	+ }
	2271	+ }
	2272	+}
	2273	+
2184	2274	static void setup_general_purpose_evm(void)
2185	2275	{
2186	2276	u32 prof_sel = am335x_get_profile_selection();
...	...	@@ -2361,6 +2451,8 @@
2361	2451	else
2362	2452	goto out;
2363	2453	}
	2454	+
	2455	+ am335x_opp_update();
2364	2456
2365	2457	return;
2366	2458