ASoC: wcd-dsp-mgr: add support for collecting memory dumps

The codec driver is notified through interrupt whenever the
DSP in codec is unresponsive/crashed. In such cases, collecting
dumps of the codec memory is useful in debugging the issues.
Change adds support in the wcd dsp manager driver to collect
the memory dumps upon notification of error interrupt.

Change-Id: Ib91cd4fc1476ee1a9ec448cde1a083070443f726
Signed-off-by: Bhalchandra Gajare <gajare@codeaurora.org>

include/sound/wcd-dsp-mgr.h

@@ -44,6 +44,8 @@ enum wdsp_event_type {
 	WDSP_EVENT_POST_DLOAD_DATA,
 	WDSP_EVENT_DLOAD_FAILED,
 
+	WDSP_EVENT_READ_SECTION,
+
 	/* DSP boot related */
 	WDSP_EVENT_PRE_BOOTUP,
 	WDSP_EVENT_DO_BOOT,
@@ -62,6 +64,7 @@ enum wdsp_event_type {
 
 enum wdsp_intr {
 	WDSP_IPC1_INTR,
+	WDSP_ERR_INTR,
 };
 
 /*
@@ -86,6 +89,12 @@ struct wdsp_img_section {
 	u8 *data;
 };
 
+struct wdsp_err_intr_arg {
+	bool mem_dumps_enabled;
+	u32 remote_start_addr;
+	size_t dump_size;
+};
+
 /*
  * wdsp_ops: ops/function callbacks for manager driver
  * @register_cmpnt_ops: components will use this to register

sound/soc/codecs/wcd-dsp-mgr.c

@@ -16,6 +16,8 @@
 #include <linux/stringify.h>
 #include <linux/of.h>
 #include <linux/component.h>
+#include <linux/dma-mapping.h>
+#include <soc/qcom/ramdump.h>
 #include <sound/wcd-dsp-mgr.h>
 #include "wcd-dsp-utils.h"
 
@@ -96,6 +98,18 @@ struct wdsp_cmpnt {
 	struct wdsp_cmpnt_ops *ops;
 };
 
+struct wdsp_ramdump_data {
+
+	/* Ramdump device */
+	void *rd_dev;
+
+	/* DMA address of the dump */
+	dma_addr_t rd_addr;
+
+	/* Virtual address of the dump */
+	void *rd_v_addr;
+};
+
 struct wdsp_mgr_priv {
 
 	/* Manager driver's struct device pointer */
@@ -130,6 +144,8 @@ struct wdsp_mgr_priv {
 
 	/* Lock for serializing ops called by components */
 	struct mutex api_mutex;
+
+	struct wdsp_ramdump_data dump_data;
 };
 
 static char *wdsp_get_cmpnt_type_string(enum wdsp_cmpnt_type type)
@@ -478,6 +494,78 @@ static struct device *wdsp_get_dev_for_cmpnt(struct device *wdsp_dev,
 	return cmpnt->cdev;
 }
 
+static int wdsp_collect_ramdumps(struct wdsp_mgr_priv *wdsp,
+				 struct wdsp_err_intr_arg *data)
+{
+	struct wdsp_img_section img_section;
+	struct ramdump_segment rd_seg;
+	int ret = 0;
+
+	if (!data) {
+		WDSP_ERR(wdsp, "Invalid data argument");
+		return -EINVAL;
+	}
+
+	if (!data->mem_dumps_enabled) {
+		WDSP_DBG(wdsp, "mem dumps are disabled");
+		return 0;
+	}
+
+	if (data->dump_size == 0 ||
+	    data->remote_start_addr < wdsp->base_addr) {
+		WDSP_ERR(wdsp, "Invalid start addr 0x%x or dump_size 0x%zx",
+			 data->remote_start_addr, data->dump_size);
+		ret = -EINVAL;
+		goto done;
+	}
+
+	if (!wdsp->dump_data.rd_dev) {
+		WDSP_ERR(wdsp, "Ramdump device is not setup");
+		ret = -ENODEV;
+		goto done;
+	}
+
+	WDSP_DBG(wdsp, "base_addr 0x%x, dump_start_addr 0x%x, dump_size 0x%zx",
+		 wdsp->base_addr, data->remote_start_addr, data->dump_size);
+
+	/* Allocate memory for dumps */
+	wdsp->dump_data.rd_v_addr = dma_alloc_coherent(wdsp->mdev,
+						       data->dump_size,
+						       &wdsp->dump_data.rd_addr,
+						       GFP_KERNEL);
+	if (!wdsp->dump_data.rd_v_addr) {
+		ret = -ENOMEM;
+		goto done;
+	}
+
+	img_section.addr = data->remote_start_addr - wdsp->base_addr;
+	img_section.size = data->dump_size;
+	img_section.data = wdsp->dump_data.rd_v_addr;
+
+	ret = wdsp_unicast_event(wdsp, WDSP_CMPNT_TRANSPORT,
+				 WDSP_EVENT_READ_SECTION,
+				 &img_section);
+	if (IS_ERR_VALUE(ret)) {
+		WDSP_ERR(wdsp, "Failed to read dumps, size 0x%zx at addr 0x%x",
+			 img_section.size, img_section.addr);
+		goto err_read_dumps;
+	}
+
+	rd_seg.address = (unsigned long) wdsp->dump_data.rd_v_addr;
+	rd_seg.size = img_section.size;
+	rd_seg.v_address = wdsp->dump_data.rd_v_addr;
+
+	ret = do_ramdump(wdsp->dump_data.rd_dev, &rd_seg, 1);
+	if (IS_ERR_VALUE(ret))
+		WDSP_ERR(wdsp, "do_ramdump failed with error %d", ret);
+
+err_read_dumps:
+	dma_free_coherent(wdsp->mdev, data->dump_size,
+			  wdsp->dump_data.rd_v_addr, wdsp->dump_data.rd_addr);
+done:
+	return ret;
+}
+
 static int wdsp_intr_handler(struct device *wdsp_dev,
 			     enum wdsp_intr intr, void *arg)
 {
@@ -495,6 +583,9 @@ static int wdsp_intr_handler(struct device *wdsp_dev,
 		ret = wdsp_unicast_event(wdsp, WDSP_CMPNT_IPC,
 					 WDSP_EVENT_IPC1_INTR, NULL);
 		break;
+	case WDSP_ERR_INTR:
+		ret = wdsp_collect_ramdumps(wdsp, arg);
+		break;
 	default:
 		ret = -EINVAL;
 		break;
@@ -585,6 +676,11 @@ static int wdsp_mgr_bind(struct device *dev)
 
 	wdsp->ops = &wdsp_ops;
 
+	/* Setup ramdump device */
+	wdsp->dump_data.rd_dev = create_ramdump_device("wdsp", dev);
+	if (!wdsp->dump_data.rd_dev)
+		dev_info(dev, "%s: create_ramdump_device failed\n", __func__);
+
 	ret = component_bind_all(dev, wdsp->ops);
 	if (IS_ERR_VALUE(ret))
 		WDSP_ERR(wdsp, "component_bind_all failed %d\n", ret);
@@ -616,6 +712,11 @@ static void wdsp_mgr_unbind(struct device *dev)
 
 	component_unbind_all(dev, wdsp->ops);
 
+	if (wdsp->dump_data.rd_dev) {
+		destroy_ramdump_device(wdsp->dump_data.rd_dev);
+		wdsp->dump_data.rd_dev = NULL;
+	}
+
 	/* Clear all status bits */
 	wdsp->status = 0x00;
 
@@ -746,6 +847,7 @@ static int wdsp_mgr_probe(struct platform_device *pdev)
 	INIT_WORK(&wdsp->load_fw_work, wdsp_load_fw_image);
 	INIT_LIST_HEAD(wdsp->seg_list);
 	mutex_init(&wdsp->api_mutex);
+	arch_setup_dma_ops(wdsp->mdev, 0, 0, NULL, 0);
 	dev_set_drvdata(mdev, wdsp);
 
 	ret = component_master_add_with_match(mdev, &wdsp_master_ops,