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Diffstat (limited to 'arch/arm/cpu/armv7/u8500/prcmu.c')
-rw-r--r--arch/arm/cpu/armv7/u8500/prcmu.c229
1 files changed, 229 insertions, 0 deletions
diff --git a/arch/arm/cpu/armv7/u8500/prcmu.c b/arch/arm/cpu/armv7/u8500/prcmu.c
new file mode 100644
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+++ b/arch/arm/cpu/armv7/u8500/prcmu.c
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+/*
+ * Copyright (C) 2009 ST-Ericsson SA
+ *
+ * Adapted from the Linux version:
+ * Author: Kumar Sanghvi <kumar.sanghvi@stericsson.com>
+ *
+ * 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 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.
+ *
+ * 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.
+ * 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.
+ */
+
+/*
+ * NOTE: This currently does not support the I2C workaround access method.
+ */
+
+#include <common.h>
+#include <config.h>
+#include <asm/io.h>
+#include <asm/arch/hardware.h>
+#include <asm/types.h>
+#include <asm/io.h>
+#include <asm/errno.h>
+#include <asm/arch/prcmu.h>
+
+/* CPU mailbox registers */
+#define PRCMU_I2C_WRITE(slave) \
+ (((slave) << 1) | I2CWRITE | (1 << 6))
+#define PRCMU_I2C_READ(slave) \
+ (((slave) << 1) | I2CREAD | (1 << 6))
+
+#define I2C_MBOX_BIT (1 << 5)
+
+static int prcmu_is_ready(void)
+{
+ int ready = readb(PRCM_XP70_CUR_PWR_STATE) == AP_EXECUTE;
+ if (!ready)
+ printf("PRCMU firmware not ready\n");
+ return ready;
+}
+
+static int wait_for_i2c_mbx_rdy(void)
+{
+ int timeout = 10000;
+
+ if (readl(PRCM_ARM_IT1_VAL) & I2C_MBOX_BIT) {
+ printf("prcmu: warning i2c mailbox was not acked\n");
+ /* clear mailbox 5 ack irq */
+ writel(I2C_MBOX_BIT, PRCM_ARM_IT1_CLEAR);
+ }
+
+ /* check any already on-going transaction */
+ while ((readl(PRCM_MBOX_CPU_VAL) & I2C_MBOX_BIT) && timeout)
+ timeout--;
+
+ if (timeout == 0)
+ return -1;
+
+ return 0;
+}
+
+static int wait_for_i2c_req_done(void)
+{
+ int timeout = 10000;
+
+ /* Set an interrupt to XP70 */
+ writel(I2C_MBOX_BIT, PRCM_MBOX_CPU_SET);
+
+ /* wait for mailbox 5 (i2c) ack */
+ while (!(readl(PRCM_ARM_IT1_VAL) & I2C_MBOX_BIT) && timeout)
+ timeout--;
+
+ if (timeout == 0)
+ return -1;
+
+ return 0;
+}
+
+/**
+ * prcmu_i2c_read - PRCMU - 4500 communication using PRCMU I2C
+ * @reg: - db8500 register bank to be accessed
+ * @slave: - db8500 register to be accessed
+ * Returns: ACK_MB5 value containing the status
+ */
+int prcmu_i2c_read(u8 reg, u16 slave)
+{
+ uint8_t i2c_status;
+ uint8_t i2c_val;
+ int ret;
+
+ if (!prcmu_is_ready())
+ return -1;
+
+ debug("\nprcmu_4500_i2c_read:bank=%x;reg=%x;\n",
+ reg, slave);
+
+ ret = wait_for_i2c_mbx_rdy();
+ if (ret) {
+ printf("prcmu_i2c_read: mailbox became not ready\n");
+ return ret;
+ }
+
+ /* prepare the data for mailbox 5 */
+ writeb(PRCMU_I2C_READ(reg), PRCM_REQ_MB5_I2COPTYPE_REG);
+ writeb((1 << 3) | 0x0, PRCM_REQ_MB5_BIT_FIELDS);
+ writeb(slave, PRCM_REQ_MB5_I2CSLAVE);
+ writeb(0, PRCM_REQ_MB5_I2CVAL);
+
+ ret = wait_for_i2c_req_done();
+ if (ret) {
+ printf("prcmu_i2c_read: mailbox request timed out\n");
+ return ret;
+ }
+
+ /* retrieve values */
+ debug("ack-mb5:transfer status = %x\n",
+ readb(PRCM_ACK_MB5_STATUS));
+ debug("ack-mb5:reg bank = %x\n", readb(PRCM_ACK_MB5) >> 1);
+ debug("ack-mb5:slave_add = %x\n",
+ readb(PRCM_ACK_MB5_SLAVE));
+ debug("ack-mb5:reg_val = %d\n", readb(PRCM_ACK_MB5_VAL));
+
+ i2c_status = readb(PRCM_ACK_MB5_STATUS);
+ i2c_val = readb(PRCM_ACK_MB5_VAL);
+ /* clear mailbox 5 ack irq */
+ writel(I2C_MBOX_BIT, PRCM_ARM_IT1_CLEAR);
+
+ if (i2c_status == I2C_RD_OK)
+ return i2c_val;
+
+ printf("prcmu_i2c_read:read return status= %d\n", i2c_status);
+ return -1;
+}
+
+/**
+ * prcmu_i2c_write - PRCMU-db8500 communication using PRCMU I2C
+ * @reg: - db8500 register bank to be accessed
+ * @slave: - db800 register to be written to
+ * @reg_data: - the data to write
+ * Returns: ACK_MB5 value containing the status
+ */
+int prcmu_i2c_write(u8 reg, u16 slave, u8 reg_data)
+{
+ uint8_t i2c_status;
+ int ret;
+
+ if (!prcmu_is_ready())
+ return -1;
+
+ debug("\nprcmu_4500_i2c_write:bank=%x;reg=%x;\n",
+ reg, slave);
+
+ ret = wait_for_i2c_mbx_rdy();
+ if (ret) {
+ printf("prcmu_i2c_write: mailbox became not ready\n");
+ return ret;
+ }
+
+ /* prepare the data for mailbox 5 */
+ writeb(PRCMU_I2C_WRITE(reg), PRCM_REQ_MB5_I2COPTYPE_REG);
+ writeb((1 << 3) | 0x0, PRCM_REQ_MB5_BIT_FIELDS);
+ writeb(slave, PRCM_REQ_MB5_I2CSLAVE);
+ writeb(reg_data, PRCM_REQ_MB5_I2CVAL);
+
+ ret = wait_for_i2c_req_done();
+ if (ret) {
+ printf("prcmu_i2c_write: mailbox request timed out\n");
+ return ret;
+ }
+
+ /* retrieve values */
+ debug("ack-mb5:transfer status = %x\n",
+ readb(PRCM_ACK_MB5_STATUS));
+ debug("ack-mb5:reg bank = %x\n", readb(PRCM_ACK_MB5) >> 1);
+ debug("ack-mb5:slave_add = %x\n",
+ readb(PRCM_ACK_MB5_SLAVE));
+ debug("ack-mb5:reg_val = %d\n", readb(PRCM_ACK_MB5_VAL));
+
+ i2c_status = readb(PRCM_ACK_MB5_STATUS);
+ debug("\ni2c_status = %x\n", i2c_status);
+ /* clear mailbox 5 ack irq */
+ writel(I2C_MBOX_BIT, PRCM_ARM_IT1_CLEAR);
+
+ if (i2c_status == I2C_WR_OK)
+ return 0;
+
+ printf("%s: i2c_status : 0x%x\n", __func__, i2c_status);
+ return -1;
+}
+
+void u8500_prcmu_enable(u32 *reg)
+{
+ writel(readl(reg) | (1 << 8), reg);
+}
+
+void db8500_prcmu_init(void)
+{
+ /* Enable timers */
+ writel(1 << 17, PRCM_TCR);
+
+ u8500_prcmu_enable((u32 *)PRCM_PER1CLK_MGT_REG);
+ u8500_prcmu_enable((u32 *)PRCM_PER2CLK_MGT_REG);
+ u8500_prcmu_enable((u32 *)PRCM_PER3CLK_MGT_REG);
+ /* PER4CLK does not exist */
+ u8500_prcmu_enable((u32 *)PRCM_PER5CLK_MGT_REG);
+ u8500_prcmu_enable((u32 *)PRCM_PER6CLK_MGT_REG);
+ /* Only exists in ED but is always ok to write to */
+ u8500_prcmu_enable((u32 *)PRCM_PER7CLK_MGT_REG);
+
+ u8500_prcmu_enable((u32 *)PRCM_UARTCLK_MGT_REG);
+ u8500_prcmu_enable((u32 *)PRCM_I2CCLK_MGT_REG);
+
+ u8500_prcmu_enable((u32 *)PRCM_SDMMCCLK_MGT_REG);
+
+ /* Clean up the mailbox interrupts after pre-u-boot code. */
+ writel(I2C_MBOX_BIT, PRCM_ARM_IT1_CLEAR);
+}
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