Merge "soc: qcom: Add sysfs node to communicate with AOP using QMP protocol"

drivers/soc/qcom/Kconfig

@@ -1247,5 +1247,13 @@ config MSM_SLATECOM_INTERFACE
 		from hardware. Hardware will provide access to read
 		registers and read/write AHB memory in the device.
 
+config QCOM_AOP_SET_DDR
+	tristate "Sysfs to communicate with AOP using QMP protocol"
+	help
+	  This options enables a driver which allows clients to send messages
+	  to Alway On processor using QMP transport. Users can echo a frequency
+	  into an exposed sysfs node to send to AOP. The driver expects the Cap
+	  frequency of DDR based on SKU.
+
 source "drivers/soc/qcom/icnss2/Kconfig"
 endmenu

drivers/soc/qcom/Makefile

@@ -112,3 +112,4 @@ obj-$(CONFIG_RENAME_BLOCK_DEVICE) += rename_block_device.o
 obj-$(CONFIG_QCOM_ADSP_MANUAL_VOTE) += adsp_vote_qmi.o adsp_lpm_voting_v01.o
 obj-$(CONFIG_MSM_SLATECOM) += slatecom_spi.o
 obj-$(CONFIG_MSM_SLATECOM_INTERFACE) += slatecom_interface.o
+obj-$(CONFIG_QCOM_AOP_SET_DDR) += aop-set-ddr.o

drivers/soc/qcom/aop-set-ddr.c

@@ -0,0 +1,87 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright (c) 2021, The Linux Foundation. All rights reserved. */
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mailbox_client.h>
+#include <linux/mailbox/qmp.h>
+#include <linux/platform_device.h>
+
+#define MAX_MSG_SIZE 96 /* Imposed by the remote */
+
+struct set_ddr_freq_data {
+	struct qmp_pkt pkt;
+	char buf[MAX_MSG_SIZE + 1];
+};
+
+static struct set_ddr_freq_data data_pkt;
+static struct mbox_chan *chan;
+static struct mbox_client *cl;
+
+static ssize_t set_ddr_capped_freq_store(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t len)
+{
+	unsigned int freq = 0;
+
+	if (kstrtou32(buf, 0, &freq)) {
+		pr_err("%s: failed to read boot info from string\n", __func__);
+		return -EINVAL;
+	}
+
+	memset(&data_pkt, 0, sizeof(data_pkt));
+	snprintf(data_pkt.buf, MAX_MSG_SIZE,
+			"{class:ddr, res:capped, val: %d}", freq);
+	pr_debug("%s : data: %s\n", __func__, data_pkt.buf);
+
+	/* Controller expects a 4 byte aligned buffer */
+	data_pkt.pkt.size = (strlen(data_pkt.buf) + 0x3) & ~0x3;
+	data_pkt.pkt.data = data_pkt.buf;
+
+	if (mbox_send_message(chan, &(data_pkt.pkt)) < 0)
+		pr_err("Failed to send qmp request\n");
+
+	return len;
+}
+static DEVICE_ATTR_WO(set_ddr_capped_freq);
+
+static int set_ddr_freq_probe(struct platform_device *pdev)
+{
+	int ret = 0;
+
+	cl = devm_kzalloc(&pdev->dev, sizeof(*cl), GFP_KERNEL);
+	if (!cl)
+		return -ENOMEM;
+
+	cl->dev = &pdev->dev;
+	cl->tx_block = true;
+	cl->tx_tout = 1000;
+	cl->knows_txdone = false;
+
+	chan = mbox_request_channel(cl, 0);
+	if (IS_ERR(chan)) {
+		dev_err(&pdev->dev, "Failed to mbox channel\n");
+		return PTR_ERR(chan);
+	}
+
+	ret = device_create_file(&pdev->dev, &dev_attr_set_ddr_capped_freq);
+	if (ret)
+		dev_err(&pdev->dev, "Couldn't create sysfs attribute\n");
+
+	return 0;
+}
+
+static const struct of_device_id aop_qmp_match_tbl[] = {
+	{.compatible = "qcom,aop-set-ddr-freq"},
+	{},
+};
+
+static struct platform_driver aop_qmp_msg_driver = {
+	.probe = set_ddr_freq_probe,
+	.driver = {
+		.name = "aop-set-ddr-freq",
+		.suppress_bind_attrs = true,
+		.of_match_table = aop_qmp_match_tbl,
+	},
+};
+builtin_platform_driver(aop_qmp_msg_driver);