drivers: soc: qcom: add initial support for rimps logging

Add initial support of rimps logging, this driver introduces
the infrastructure required to collect the logs received from
rimps and dump into ipc logging buffers.

Change-Id: Ic7b86fcf5935ada5fa5008774a9363faa40960ce
Signed-off-by: Santosh Mardi <gsantosh@codeaurora.org>

drivers/soc/qcom/Kconfig

@@ -745,6 +745,17 @@ config QTI_HW_MEMLAT_SCMI_CLIENT
 	  driver, and interface driver will use this handle to communicate with
 	  memlat HW.
 
+config QTI_HW_MEMLAT_LOG
+	tristate "Qualcomm Technologies Inc. HW MEMLAT Logging"
+	depends on IPC_LOGGING && QCOM_RIMPS
+	default n
+	help
+	  Memlat hw logging driver, this driver has the infra to collect logs
+	  generated in MEMLAT HW and log the buffers.
+
+	  This driver register with IPC_Logging framework, to have dedicated
+	  buffer for memlat hw device.
+
 if MSM_PM
 menuconfig MSM_IDLE_STATS
 	bool "Collect idle statistics"

drivers/soc/qcom/Makefile

@@ -95,4 +95,4 @@ obj-$(CONFIG_QTI_SYS_PM_VX) += sys_pm_vx.o
 obj-$(CONFIG_ICNSS2) += icnss2/
 obj-$(CONFIG_QTI_HW_MEMLAT_SCMI_CLIENT)	+= memlat_scmi.o
 obj-$(CONFIG_QTI_HW_MEMLAT) += rimps_memlat.o
-
+obj-$(CONFIG_QTI_HW_MEMLAT_LOG)	+= rimps_log.o

drivers/soc/qcom/rimps_log.c

@@ -0,0 +1,373 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2020, The Linux Foundation. All rights reserved.
+ */
+
+#include <linux/kernel.h>
+#include <linux/mailbox_client.h>
+#include <linux/module.h>
+#include <linux/of_platform.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/io.h>
+#include <linux/ipc_logging.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+#define NUM_LOG_PAGES		10
+#define MAX_PRINT_SIZE		200
+#define MAX_BUF_NUM		10
+#define MAX_RESIDUAL_SIZE	MAX_PRINT_SIZE
+#define LOG_ID_MARKER	0x474F4C
+#define LOG_ID_MARKER_SHIFT	24
+#define LOG_ID_MARKER_MASK	0xFFFFFF
+#define LOG_ID_MASK	0xFF
+#define SIZE_ADJUST	4
+#define SRC_OFFSET	4
+
+enum sync_mode {
+	ping_pong,
+	log_id
+};
+
+struct remote_mem {
+	void __iomem *start;
+	unsigned long long size;
+};
+
+struct rimps_buf {
+	struct list_head node;
+	char *buf;
+	u32 size;
+	u32 cpy_idx;
+};
+
+struct rimps_log_info {
+	struct remote_mem *rmem;
+	struct mbox_client cl;
+	struct mbox_chan *ch;
+	struct delayed_work work;
+	struct device *dev;
+	void __iomem *base;
+	void *ipc_log_ctxt;
+	enum sync_mode sync_mode;
+	unsigned int rmem_idx;
+	unsigned int num_bufs;
+	char *rem_buf;
+	char *glb_buf;
+	int  rem_len;
+	spinlock_t free_list_lock;
+	spinlock_t full_list_lock;
+};
+
+static LIST_HEAD(full_buffers_list);
+static LIST_HEAD(free_buffers_list);
+static struct workqueue_struct *rimps_wq;
+
+static inline int get_next_logbuf(char *buf, int size)
+{
+	int i;
+
+	for (i = (size - 1); i >= 0 ; i--) {
+		if (buf[i] == '\n')
+			break;
+	}
+	if (i >= 0)
+		buf[i] = '\0';
+	else
+		return size;
+
+	return i + 1;
+}
+
+static void rimps_log_work(struct work_struct *work)
+{
+	struct rimps_log_info *info = container_of(work,
+						struct rimps_log_info,
+						work.work);
+	char *src;
+	int buf_start = 0;
+	int cnt = 0, print_size = 0, buf_size = 0;
+	char c;
+	struct rimps_buf *buf_node;
+	unsigned long flags;
+
+	while (1) {
+		spin_lock_irqsave(&info->full_list_lock, flags);
+		if (list_empty(&full_buffers_list)) {
+			spin_unlock_irqrestore(&info->full_list_lock, flags);
+			return;
+		}
+		buf_node = list_first_entry(&full_buffers_list,
+					struct rimps_buf, node);
+		list_del(&buf_node->node);
+		spin_unlock_irqrestore(&info->full_list_lock, flags);
+		buf_start = buf_node->cpy_idx - info->rem_len;
+		if (info->rem_len)
+			memcpy(&buf_node->buf[buf_start],
+					info->rem_buf, info->rem_len);
+		src = &buf_node->buf[buf_start];
+		buf_size = buf_node->size + info->rem_len;
+		do {
+			print_size = (buf_size >= MAX_PRINT_SIZE) ?
+						MAX_PRINT_SIZE : buf_size;
+			cnt = get_next_logbuf(src, print_size);
+			if (cnt == print_size) {
+				if (buf_size < MAX_PRINT_SIZE) {
+					info->rem_len = buf_size;
+					memcpy(info->rem_buf, src, buf_size);
+					goto out;
+				} else {
+					c = src[cnt - 1];
+					src[cnt - 1] = '\0';
+					ipc_log_string(info->ipc_log_ctxt,
+							"%s%c\n", src, c);
+				}
+			} else {
+				ipc_log_string(info->ipc_log_ctxt,
+						"%s\n", src, c);
+			}
+
+			buf_start += cnt;
+			buf_size -= cnt;
+			src = &buf_node->buf[buf_start];
+		} while (buf_size > 0);
+out:
+		spin_lock_irqsave(&info->free_list_lock, flags);
+		list_add_tail(&buf_node->node, &free_buffers_list);
+		spin_unlock_irqrestore(&info->free_list_lock, flags);
+	}
+}
+
+static struct rimps_buf *get_free_buffer(struct rimps_log_info *info)
+{
+	struct rimps_buf *buf_node;
+	unsigned long flags;
+
+	spin_lock_irqsave(&info->free_list_lock, flags);
+	if (list_empty(&free_buffers_list)) {
+		spin_unlock_irqrestore(&info->free_list_lock, flags);
+		return NULL;
+	}
+
+	buf_node = list_first_entry(&free_buffers_list,
+					struct rimps_buf, node);
+	list_del(&buf_node->node);
+	spin_unlock_irqrestore(&info->free_list_lock, flags);
+	return buf_node;
+}
+
+
+static void rimps_log_rx(struct mbox_client *client, void *msg)
+{
+	struct rimps_log_info *info = dev_get_drvdata(client->dev);
+	struct device *dev = info->dev;
+	struct rimps_buf *buf_node;
+	struct remote_mem *rmem;
+	void __iomem *src;
+	u32 marker;
+	unsigned long long rmem_size;
+	unsigned long flags;
+	int src_offset = 0;
+	int size_adj = 0;
+
+	buf_node = get_free_buffer(info);
+	if (!buf_node) {
+		dev_err(dev, "global buffer full dropping buffers\n");
+		return;
+	}
+
+	if (info->sync_mode == log_id) {
+		marker = *(u32 *)(info->rmem)->start;
+		if ((marker & LOG_ID_MARKER_MASK) != LOG_ID_MARKER) {
+			pr_err("%s: Log signature incorrect\n", __func__);
+			return;
+		}
+		info->rmem_idx = ((marker >> LOG_ID_MARKER_SHIFT)
+					& LOG_ID_MASK);
+		if (info->rmem_idx >= info->num_bufs) {
+			dev_err(dev, "wrong index id dropping\n");
+			return;
+		}
+		if (info->rmem_idx == 0) {
+			size_adj = SIZE_ADJUST;
+			src_offset = SRC_OFFSET;
+		}
+	}
+
+	rmem = info->rmem + info->rmem_idx;
+	rmem_size = rmem->size - size_adj;
+	src = rmem->start + src_offset;
+	memcpy_fromio(&buf_node->buf[buf_node->cpy_idx],
+				src, rmem_size);
+	buf_node->size = rmem_size;
+	spin_lock_irqsave(&info->full_list_lock, flags);
+	list_add_tail(&buf_node->node, &full_buffers_list);
+	spin_unlock_irqrestore(&info->full_list_lock, flags);
+
+	if (!delayed_work_pending(&info->work))
+		queue_delayed_work(rimps_wq, &info->work, 0);
+
+	if (info->sync_mode == ping_pong) {
+		info->rmem_idx++;
+		if (info->rmem_idx == info->num_bufs)
+			info->rmem_idx = 0;
+	}
+}
+
+static int populate_free_buffers(struct rimps_log_info *info,
+							int rmem_size)
+{
+	int i = 0;
+	struct rimps_buf *buf_nodes;
+
+	buf_nodes = devm_kzalloc(info->dev,
+				MAX_BUF_NUM * sizeof(struct rimps_buf),
+				GFP_KERNEL);
+	if (!buf_nodes)
+		return -ENOMEM;
+
+	for (i = 0; i < MAX_BUF_NUM; i++) {
+		buf_nodes[i].buf = &info->glb_buf[i * (rmem_size + MAX_PRINT_SIZE)];
+		buf_nodes[i].size = rmem_size;
+		buf_nodes[i].cpy_idx = MAX_PRINT_SIZE;
+		list_add_tail(&buf_nodes[i].node, &free_buffers_list);
+	}
+	return 0;
+}
+
+static int rimps_log_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct rimps_log_info *info;
+	struct mbox_client *cl;
+	int ret, i = 0;
+	struct resource *res;
+	void __iomem *mem_base;
+	struct remote_mem *rmem;
+	int prev_size = 0;
+
+	info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL);
+	if (!info)
+		return -ENOMEM;
+
+	info->dev = dev;
+
+	rmem = kcalloc(pdev->num_resources, sizeof(struct remote_mem),
+			GFP_KERNEL);
+	if (!rmem)
+		return -ENOMEM;
+
+	info->rmem = rmem;
+
+	for (i = 0; i < pdev->num_resources; i++) {
+		struct remote_mem *rmem = &info->rmem[i];
+
+		res = platform_get_resource(pdev, IORESOURCE_MEM, i);
+		if (!res) {
+			dev_err(dev,
+				"Failed to get the device base address\n");
+			ret = -ENODEV;
+			goto exit;
+		}
+
+		mem_base = devm_ioremap(&pdev->dev, res->start,
+					resource_size(res));
+		if (IS_ERR(mem_base)) {
+			ret =  PTR_ERR(mem_base);
+			goto exit;
+		}
+		rmem->start = mem_base;
+		rmem->size = resource_size(res);
+		if (prev_size && (rmem->size != prev_size)) {
+			ret = -EINVAL;
+			goto exit;
+		} else if (!prev_size) {
+			prev_size = rmem->size;
+		}
+		info->num_bufs++;
+	}
+	info->glb_buf = devm_kzalloc(dev, MAX_BUF_NUM *
+					(rmem->size + MAX_PRINT_SIZE),
+					GFP_KERNEL);
+	if (!info->glb_buf) {
+		ret = -ENOMEM;
+		goto exit;
+	}
+
+	info->rem_buf = devm_kzalloc(dev, MAX_RESIDUAL_SIZE, GFP_KERNEL);
+	if (!info->rem_buf) {
+		ret = -ENOMEM;
+		goto exit;
+	}
+
+	ret = populate_free_buffers(info, rmem->size);
+	if (ret < 0)
+		goto exit;
+
+	info->sync_mode = log_id;
+
+	cl = &info->cl;
+	cl->dev = dev;
+	cl->tx_block = false;
+	cl->knows_txdone = true;
+	cl->rx_callback = rimps_log_rx;
+
+	info->ch = mbox_request_channel(cl, 0);
+	if (IS_ERR(info->ch)) {
+		ret = PTR_ERR(info->ch);
+		if (ret != -EPROBE_DEFER)
+			dev_err(dev, "Failed to request mbox info: %d\n", ret);
+		goto exit;
+	}
+	info->ipc_log_ctxt = ipc_log_context_create(NUM_LOG_PAGES,
+					dev_name(dev), 0);
+	if (!info->ipc_log_ctxt) {
+		dev_err(dev, "failed to create log context\n");
+		ret = -ENOMEM;
+		goto exit;
+	}
+
+	dev_set_drvdata(dev, info);
+	INIT_DEFERRABLE_WORK(&info->work, &rimps_log_work);
+	spin_lock_init(&info->free_list_lock);
+	spin_lock_init(&info->full_list_lock);
+	rimps_wq = create_freezable_workqueue("rimps_wq");
+	dev_info(dev, "RIMPS logging initialized\n");
+
+	return 0;
+
+exit:
+	kfree(info->rmem);
+	return ret;
+}
+
+static int rimps_log_remove(struct platform_device *pdev)
+{
+	struct rimps_log_info *info;
+
+	info = dev_get_drvdata(&pdev->dev);
+
+	mbox_free_channel(info->ch);
+
+	return 0;
+}
+
+static const struct of_device_id rimps_log[] = {
+	{.compatible = "qcom,rimps-log"},
+	{},
+};
+
+
+static struct platform_driver rimps_log_driver = {
+	.driver = {
+		.name = "rimps-log",
+		.of_match_table = rimps_log,
+	},
+	.probe = rimps_log_probe,
+	.remove = rimps_log_remove,
+};
+builtin_platform_driver(rimps_log_driver);
+
+MODULE_LICENSE("GPL v2");