Add support for Xilinx Zynq UltraScale+ MPSOC

The Xilinx Zynq UltraScale+ MPSOC containes a quad A53 cluster. This
patch adds the platform port for that SoC.

Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com>
diff --git a/plat/xilinx/zynqmp/pm_service/pm_ipi.c b/plat/xilinx/zynqmp/pm_service/pm_ipi.c
new file mode 100644
index 0000000..ef2b4fe
--- /dev/null
+++ b/plat/xilinx/zynqmp/pm_service/pm_ipi.c
@@ -0,0 +1,247 @@
+/*
+ * Copyright (c) 2013-2016, ARM Limited and Contributors. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * Redistributions of source code must retain the above copyright notice, this
+ * list of conditions and the following disclaimer.
+ *
+ * Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ * Neither the name of ARM nor the names of its contributors may be used
+ * to endorse or promote products derived from this software without specific
+ * prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <bakery_lock.h>
+#include <mmio.h>
+#include <platform.h>
+#include <arch_helpers.h>
+#include "pm_ipi.h"
+#include "../zynqmp_private.h"
+
+/* IPI message buffers */
+#define IPI_BUFFER_BASEADDR	0xFF990000U
+
+#define IPI_BUFFER_RPU_0_BASE	(IPI_BUFFER_BASEADDR + 0x0U)
+#define IPI_BUFFER_RPU_1_BASE	(IPI_BUFFER_BASEADDR + 0x200U)
+#define IPI_BUFFER_APU_BASE	(IPI_BUFFER_BASEADDR + 0x400U)
+#define IPI_BUFFER_PL_0_BASE	(IPI_BUFFER_BASEADDR + 0x600U)
+#define IPI_BUFFER_PL_1_BASE	(IPI_BUFFER_BASEADDR + 0x800U)
+#define IPI_BUFFER_PL_2_BASE	(IPI_BUFFER_BASEADDR + 0xA00U)
+#define IPI_BUFFER_PL_3_BASE	(IPI_BUFFER_BASEADDR + 0xC00U)
+#define IPI_BUFFER_PMU_BASE	(IPI_BUFFER_BASEADDR + 0xE00U)
+
+#define IPI_BUFFER_TARGET_RPU_0_OFFSET	0x0U
+#define IPI_BUFFER_TARGET_RPU_1_OFFSET	0x40U
+#define IPI_BUFFER_TARGET_APU_OFFSET	0x80U
+#define IPI_BUFFER_TARGET_PL_0_OFFSET	0xC0U
+#define IPI_BUFFER_TARGET_PL_1_OFFSET	0x100U
+#define IPI_BUFFER_TARGET_PL_2_OFFSET	0x140U
+#define IPI_BUFFER_TARGET_PL_3_OFFSET	0x180U
+#define IPI_BUFFER_TARGET_PMU_OFFSET	0x1C0U
+
+#define IPI_BUFFER_REQ_OFFSET	0x0U
+#define IPI_BUFFER_RESP_OFFSET	0x20U
+
+/* IPI Base Address */
+#define IPI_BASEADDR		0XFF300000
+
+/* APU's IPI registers */
+#define IPI_APU_ISR		(IPI_BASEADDR + 0X00000010)
+#define IPI_APU_IER		(IPI_BASEADDR + 0X00000018)
+#define IPI_APU_IDR		(IPI_BASEADDR + 0X0000001C)
+#define IPI_APU_ISR_PMU_0_MASK		0X00010000
+#define IPI_APU_IER_PMU_0_MASK		0X00010000
+
+#define IPI_TRIG_OFFSET		0
+#define IPI_OBS_OFFSET		4
+
+/* Power Management IPI interrupt number */
+#define PM_INT_NUM		0
+#define IPI_PMU_PM_INT_BASE	(IPI_PMU_0_TRIG + (PM_INT_NUM * 0x1000))
+#define IPI_PMU_PM_INT_MASK	(IPI_APU_ISR_PMU_0_MASK << PM_INT_NUM)
+#if (PM_INT_NUM < 0 || PM_INT_NUM > 3)
+	#error PM_INT_NUM value out of range
+#endif
+
+#define IPI_APU_MASK		1U
+
+static bakery_lock_t pm_secure_lock;
+
+const struct pm_ipi apu_ipi = {
+	.mask = IPI_APU_MASK,
+	.base = IPI_BASEADDR,
+	.buffer_base = IPI_BUFFER_APU_BASE,
+};
+
+/**
+ * pm_ipi_init() - Initialize IPI peripheral for communication with PMU
+ *
+ * @return	On success, the initialization function must return 0.
+ *		Any other return value will cause the framework to ignore
+ *		the service
+ *
+ * Enable interrupts at registered entrance in IPI peripheral
+ * Called from pm_setup initialization function
+ */
+int pm_ipi_init(void)
+{
+	bakery_lock_init(&pm_secure_lock);
+
+	/* IPI Interrupts Clear & Disable */
+	mmio_write_32(IPI_APU_ISR, 0xffffffff);
+	mmio_write_32(IPI_APU_IDR, 0xffffffff);
+
+	return 0;
+}
+
+/**
+ * pm_ipi_wait() - wait for pmu to handle request
+ * @proc	proc which is waiting for PMU to handle request
+ */
+static enum pm_ret_status pm_ipi_wait(const struct pm_proc *proc)
+{
+	int status;
+
+	/* Wait until previous interrupt is handled by PMU */
+	do {
+		status = mmio_read_32(proc->ipi->base + IPI_OBS_OFFSET) &
+					IPI_PMU_PM_INT_MASK;
+		/* TODO: 1) Use timer to add delay between read attempts */
+		/* TODO: 2) Return PM_RET_ERR_TIMEOUT if this times out */
+	} while (status);
+
+	return PM_RET_SUCCESS;
+}
+
+/**
+ * pm_ipi_send_common() - Sends IPI request to the PMU
+ * @proc	Pointer to the processor who is initiating request
+ * @payload	API id and call arguments to be written in IPI buffer
+ *
+ * Send an IPI request to the power controller. Caller needs to hold
+ * the 'pm_secure_lock' lock.
+ *
+ * @return	Returns status, either success or error+reason
+ */
+static enum pm_ret_status pm_ipi_send_common(const struct pm_proc *proc,
+					     uint32_t payload[PAYLOAD_ARG_CNT])
+{
+	unsigned int offset = 0;
+	uintptr_t buffer_base = proc->ipi->buffer_base +
+					IPI_BUFFER_TARGET_PMU_OFFSET +
+					IPI_BUFFER_REQ_OFFSET;
+
+	/* Wait until previous interrupt is handled by PMU */
+	pm_ipi_wait(proc);
+
+	/* Write payload into IPI buffer */
+	for (size_t i = 0; i < PAYLOAD_ARG_CNT; i++) {
+		mmio_write_32(buffer_base + offset, payload[i]);
+		offset += PAYLOAD_ARG_SIZE;
+	}
+	/* Generate IPI to PMU */
+	mmio_write_32(proc->ipi->base + IPI_TRIG_OFFSET, IPI_PMU_PM_INT_MASK);
+
+	return PM_RET_SUCCESS;
+}
+
+/**
+ * pm_ipi_send() - Sends IPI request to the PMU
+ * @proc	Pointer to the processor who is initiating request
+ * @payload	API id and call arguments to be written in IPI buffer
+ *
+ * Send an IPI request to the power controller.
+ *
+ * @return	Returns status, either success or error+reason
+ */
+enum pm_ret_status pm_ipi_send(const struct pm_proc *proc,
+			       uint32_t payload[PAYLOAD_ARG_CNT])
+{
+	enum pm_ret_status ret;
+
+	bakery_lock_get(&pm_secure_lock);
+
+	ret = pm_ipi_send_common(proc, payload);
+
+	bakery_lock_release(&pm_secure_lock);
+
+	return ret;
+}
+
+
+/**
+ * pm_ipi_buff_read() - Reads IPI response after PMU has handled interrupt
+ * @proc	Pointer to the processor who is waiting and reading response
+ * @value	Used to return value from 2nd IPI buffer element (optional)
+ *
+ * @return	Returns status, either success or error+reason
+ */
+static enum pm_ret_status pm_ipi_buff_read(const struct pm_proc *proc,
+					   unsigned int *value)
+{
+	uintptr_t buffer_base = proc->ipi->buffer_base +
+				IPI_BUFFER_TARGET_PMU_OFFSET +
+				IPI_BUFFER_RESP_OFFSET;
+
+	pm_ipi_wait(proc);
+
+	/*
+	 * Read response from IPI buffer
+	 * buf-0: success or error+reason
+	 * buf-1: value
+	 * buf-2: unused
+	 * buf-3: unused
+	 */
+	if (value != NULL)
+		*value = mmio_read_32(buffer_base + PAYLOAD_ARG_SIZE);
+
+	return mmio_read_32(buffer_base);
+}
+
+/**
+ * pm_ipi_send_sync() - Sends IPI request to the PMU
+ * @proc	Pointer to the processor who is initiating request
+ * @payload	API id and call arguments to be written in IPI buffer
+ * @value	Used to return value from 2nd IPI buffer element (optional)
+ *
+ * Send an IPI request to the power controller and wait for it to be handled.
+ *
+ * @return	Returns status, either success or error+reason and, optionally,
+ *		@value
+ */
+enum pm_ret_status pm_ipi_send_sync(const struct pm_proc *proc,
+				    uint32_t payload[PAYLOAD_ARG_CNT],
+				    unsigned int *value)
+{
+	enum pm_ret_status ret;
+
+	bakery_lock_get(&pm_secure_lock);
+
+	ret = pm_ipi_send_common(proc, payload);
+	if (ret != PM_RET_SUCCESS)
+		goto unlock;
+
+	ret = pm_ipi_buff_read(proc, value);
+
+unlock:
+	bakery_lock_release(&pm_secure_lock);
+
+	return ret;
+}