[PATCH v2 2/6] soc: Mediatek: Add SCPSYS CPU power domain driver

[Scott Shu <scott.shu@mediatek.com>]

This adds a CPU power domain driver for the Mediatek SCPSYS unit on
MT6580.

Signed-off-by: Scott Shu <scott.shu@mediatek.com>
---
 arch/arm/mach-mediatek/Makefile  |   2 +-
 arch/arm/mach-mediatek/generic.h |  23 ++++
 arch/arm/mach-mediatek/hotplug.c | 267 +++++++++++++++++++++++++++++++++++++++
 3 files changed, 291 insertions(+), 1 deletion(-)
 create mode 100644 arch/arm/mach-mediatek/generic.h
 create mode 100644 arch/arm/mach-mediatek/hotplug.c

diff --git a/arch/arm/mach-mediatek/Makefile b/arch/arm/mach-mediatek/Makefile
index 2116460..b2e4ef5 100644
--- a/arch/arm/mach-mediatek/Makefile
+++ b/arch/arm/mach-mediatek/Makefile
@@ -1,4 +1,4 @@
 ifeq ($(CONFIG_SMP),y)
-obj-$(CONFIG_ARCH_MEDIATEK) += platsmp.o
+obj-$(CONFIG_ARCH_MEDIATEK) += platsmp.o hotplug.o
 endif
 obj-$(CONFIG_ARCH_MEDIATEK) += mediatek.o
diff --git a/arch/arm/mach-mediatek/generic.h b/arch/arm/mach-mediatek/generic.h
new file mode 100644
index 0000000..376f183
--- /dev/null
+++ b/arch/arm/mach-mediatek/generic.h
@@ -0,0 +1,23 @@
+/*
+ * Copyright (c) 2015 Mediatek Inc.
+ * Author: Scott Shu <scott.shu@mediatek.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 in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+#ifndef __MACH_GENERIC_H
+#define __MACH_GENERIC_H
+
+#include <linux/kernel.h>
+
+int spm_cpu_mtcmos_init(void);
+int spm_cpu_mtcmos_on(int cpu);
+int spm_cpu_mtcmos_off(int cpu, bool wfi);
+
+#endif
diff --git a/arch/arm/mach-mediatek/hotplug.c b/arch/arm/mach-mediatek/hotplug.c
new file mode 100644
index 0000000..bd97f2e
--- /dev/null
+++ b/arch/arm/mach-mediatek/hotplug.c
@@ -0,0 +1,267 @@
+/*
+ * Copyright (c) 2015 Mediatek Inc.
+ * Author: Scott Shu <scott.shu@mediatek.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 in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/spinlock.h>
+#include <linux/delay.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/of_address.h>
+
+/* SCPSYS registers */
+#define SPM_POWERON_CONFIG_SET		0x0000
+
+#define SPM_CA7_CPU0_PWR_CON		0x0200
+#define SPM_CA7_CPU1_PWR_CON		0x0218
+#define SPM_CA7_CPU2_PWR_CON		0x021c
+#define SPM_CA7_CPU3_PWR_CON		0x0220
+
+#define SPM_CA7_CPU0_L1_PDN		0x025c
+#define SPM_CA7_CPU1_L1_PDN		0x0264
+#define SPM_CA7_CPU2_L1_PDN		0x026c
+#define SPM_CA7_CPU3_L1_PDN		0x0274
+
+#define SPM_PWR_STATUS			0x060c
+#define SPM_PWR_STATUS_2ND		0x0610
+#define SPM_SLEEP_TIMER_STA		0x0720
+
+/* bit definition in SPM_CA7_CPUx_PWR_CON */
+#define SRAM_ISOINT_B		BIT(6)
+#define SRAM_CKISO		BIT(5)
+#define PWR_CLK_DIS		BIT(4)
+#define PWR_ON_2ND		BIT(3)
+#define PWR_ON			BIT(2)
+#define PWR_ISO			BIT(1)
+#define PWR_RST_B		BIT(0)
+
+/* bit definition in SPM_CA7_CPUx_L1_PDN */
+#define L1_PDN_ACK		BIT(8)
+#define L1_PDN			BIT(0)
+
+#define MT6580_MAX_CPUS		4
+
+static DEFINE_SPINLOCK(spm_cpu_lock);
+
+void __iomem *spm_cpu_base;
+
+u32 spm_cpu_pwr_con[MT6580_MAX_CPUS] = {
+	SPM_CA7_CPU0_PWR_CON,
+	SPM_CA7_CPU1_PWR_CON,
+	SPM_CA7_CPU2_PWR_CON,
+	SPM_CA7_CPU3_PWR_CON,
+};
+
+u32 spm_cpu_l1_pdn[MT6580_MAX_CPUS] = {
+	SPM_CA7_CPU0_L1_PDN,
+	SPM_CA7_CPU1_L1_PDN,
+	SPM_CA7_CPU2_L1_PDN,
+	SPM_CA7_CPU3_L1_PDN,
+};
+
+#define SPM_REGWR_EN		BIT(0)
+#define SPM_PROJECT_CODE	0x0B16
+
+int spm_cpu_mtcmos_on(int cpu)
+{
+	unsigned long flags;
+	static u32 spmcpu_pwr_con, spmcpu_l1_pdn;
+	unsigned int temp;
+	int timeout = 10;
+	int ret = -ENOSYS;
+
+	temp = (SPM_PROJECT_CODE << 16) | SPM_REGWR_EN;
+	writel_relaxed(temp, spm_cpu_base + SPM_POWERON_CONFIG_SET);
+
+	spmcpu_pwr_con = spm_cpu_pwr_con[cpu];
+	spmcpu_l1_pdn = spm_cpu_l1_pdn[cpu];
+
+	spin_lock_irqsave(&spm_cpu_lock, flags);
+
+	/* Set PWR_ON */
+	temp = readl_relaxed(spm_cpu_base + spmcpu_pwr_con);
+	temp |= PWR_ON;
+	writel_relaxed(temp, spm_cpu_base + spmcpu_pwr_con);
+
+	/* Wait for charging core power */
+	udelay(1);
+
+	/* Set PWR_ON_2ND */
+	temp = readl_relaxed(spm_cpu_base + spmcpu_pwr_con);
+	temp |= PWR_ON_2ND;
+	writel_relaxed(temp, spm_cpu_base + spmcpu_pwr_con);
+
+	/* Wait for the power-ack */
+	while (((readl_relaxed(spm_cpu_base + SPM_PWR_STATUS) &
+		(1U << (13 - cpu))) != (1U << (13 - cpu))) ||
+		((readl_relaxed(spm_cpu_base + SPM_PWR_STATUS_2ND) &
+		(1U << (13 - cpu))) != (1U << (13 - cpu)))) {
+		if (--timeout == 0)
+			goto fail;
+		udelay(1);
+	}
+
+	temp = readl_relaxed(spm_cpu_base + spmcpu_pwr_con);
+	temp &= ~PWR_ISO;
+	writel_relaxed(temp, spm_cpu_base + spmcpu_pwr_con);
+
+	/* L1 power on */
+	temp = readl_relaxed(spm_cpu_base + spmcpu_l1_pdn);
+	temp &= ~L1_PDN;
+	writel_relaxed(temp, spm_cpu_base + spmcpu_l1_pdn);
+	timeout = 10;
+	while ((readl_relaxed(spm_cpu_base + spmcpu_l1_pdn) &
+		L1_PDN_ACK) != 0) {
+		if (--timeout == 0)
+			goto fail;
+		udelay(1);
+	}
+
+	/* Wait for memory power ready */
+	udelay(1);
+
+	/* Set SRAM_ISOINT_B */
+	temp = readl_relaxed(spm_cpu_base + spmcpu_pwr_con);
+	temp |= SRAM_ISOINT_B;
+	writel_relaxed(temp, spm_cpu_base + spmcpu_pwr_con);
+
+	/* Clear SRAM_CKISO */
+	temp = readl_relaxed(spm_cpu_base + spmcpu_pwr_con);
+	temp &= ~SRAM_CKISO;
+	writel_relaxed(temp, spm_cpu_base + spmcpu_pwr_con);
+
+	/* Clear PWR_CLK_DIS */
+	temp = readl_relaxed(spm_cpu_base + spmcpu_pwr_con);
+	temp &= ~PWR_CLK_DIS;
+	writel_relaxed(temp, spm_cpu_base + spmcpu_pwr_con);
+
+	/* Set PWR_RST_B to finish power on and reset sequences */
+	temp = readl_relaxed(spm_cpu_base + spmcpu_pwr_con);
+	temp |= PWR_RST_B;
+	writel_relaxed(temp, spm_cpu_base + spmcpu_pwr_con);
+
+	ret = 0;
+fail:
+	spin_unlock_irqrestore(&spm_cpu_lock, flags);
+
+	return ret;
+}
+
+int spm_cpu_mtcmos_off(int cpu, bool wfi)
+{
+	unsigned long flags;
+	static u32 spmcpu_pwr_con, spmcpu_l1_pdn;
+	unsigned int temp;
+	int timeout = 10;
+	int ret = -ENOSYS;
+
+	temp = (SPM_PROJECT_CODE << 16) | SPM_REGWR_EN;
+	writel_relaxed(temp, spm_cpu_base + SPM_POWERON_CONFIG_SET);
+
+	spmcpu_pwr_con = spm_cpu_pwr_con[cpu];
+	spmcpu_l1_pdn = spm_cpu_l1_pdn[cpu];
+
+	if (wfi) {
+		while ((readl_relaxed(spm_cpu_base + SPM_SLEEP_TIMER_STA) &
+			(1U << (16 + cpu))) == 0) {
+			if (--timeout == 0)
+				return ret;
+			udelay(1);
+		}
+	}
+
+	spin_lock_irqsave(&spm_cpu_lock, flags);
+
+	/* Set PWR_ISO */
+	temp = readl_relaxed(spm_cpu_base + spmcpu_pwr_con);
+	temp |= PWR_ISO;
+	writel_relaxed(temp, spm_cpu_base + spmcpu_pwr_con);
+
+	/* Set SRAM_CKISO */
+	temp = readl_relaxed(spm_cpu_base + spmcpu_pwr_con);
+	temp |= SRAM_CKISO;
+	writel_relaxed(temp, spm_cpu_base + spmcpu_pwr_con);
+
+	/* Clear SRAM_ISOINT_B */
+	temp = readl_relaxed(spm_cpu_base + spmcpu_pwr_con);
+	temp &= ~SRAM_ISOINT_B;
+	writel_relaxed(temp, spm_cpu_base + spmcpu_pwr_con);
+
+	/* L1 power off */
+	temp = readl_relaxed(spm_cpu_base + spmcpu_l1_pdn);
+	temp |= L1_PDN;
+	writel_relaxed(temp, spm_cpu_base + spmcpu_l1_pdn);
+	timeout = 10;
+	while ((readl_relaxed(spm_cpu_base + spmcpu_l1_pdn) &
+		L1_PDN_ACK) != L1_PDN_ACK) {
+		if (--timeout == 0)
+			goto fail;
+		udelay(1);
+	}
+
+	/* Clear PWR_RST_B */
+	temp = readl_relaxed(spm_cpu_base + spmcpu_pwr_con);
+	temp &= ~PWR_RST_B;
+	writel_relaxed(temp, spm_cpu_base + spmcpu_pwr_con);
+
+	/* Set PWR_CLK_DIS */
+	temp = readl_relaxed(spm_cpu_base + spmcpu_pwr_con);
+	temp |= PWR_CLK_DIS;
+	writel_relaxed(temp, spm_cpu_base + spmcpu_pwr_con);
+
+	/* Clear PWR_ON */
+	temp = readl_relaxed(spm_cpu_base + spmcpu_pwr_con);
+	temp &= ~PWR_ON;
+	writel_relaxed(temp, spm_cpu_base + spmcpu_pwr_con);
+
+	/* Clear PWR_ON_2ND */
+	temp = readl_relaxed(spm_cpu_base + spmcpu_pwr_con);
+	temp &= ~PWR_ON_2ND;
+	writel_relaxed(temp, spm_cpu_base + spmcpu_pwr_con);
+
+	timeout = 10;
+	while (((readl_relaxed(spm_cpu_base + SPM_PWR_STATUS) &
+		(1U << (13 - cpu))) != 0) ||
+	       ((readl_relaxed(spm_cpu_base + SPM_PWR_STATUS_2ND) &
+		(1U << (13 - cpu))) != 0)) {
+		if (--timeout == 0)
+			goto fail;
+		udelay(1);
+	}
+
+	ret = 0;
+fail:
+	spin_unlock_irqrestore(&spm_cpu_lock, flags);
+
+	return ret;
+}
+
+int spm_cpu_mtcmos_init(void)
+{
+	struct device_node *node;
+
+	node = of_find_compatible_node(NULL, NULL, "mediatek,mt6580-scpsys");
+	if (!node) {
+		pr_err("Missing mt6580-scpsys node in the device tree\n");
+		return -ENODEV;
+	}
+
+	spm_cpu_base = of_iomap(node, 0);
+	if (!spm_cpu_base) {
+		pr_err("%s: Unable to map I/O memory\n", __func__);
+		return -ENODEV;
+	}
+
+	return 0;
+}
-- 
1.8.1.1.dirty