wil6210: Add pmc debug mechanism memory management

Pmc is a hardware debug mechanism which allows capturing phy data,
packets, and internally generated events and messages synchronized
and time stamped by the hardware. It requires memory buffers
allocated by the driver in order to be used by hardware dma to
upstream real time debug data to host memory.
Driver will handle memory allocation and release, and fetching
the data from the memory to application layer via debug file
system. The configuration of pmc is handled entirely by the
application layer.

Signed-off-by: Vladimir Shulman <qca_shulmanv@qca.qualcomm.com>
Signed-off-by: Vladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>

drivers/net/wireless/ath/wil6210/Makefile

@@ -12,6 +12,7 @@ wil6210-y += debug.o
 wil6210-y += rx_reorder.o
 wil6210-y += ioctl.o
 wil6210-y += fw.o
+wil6210-y += pmc.o
 wil6210-$(CONFIG_WIL6210_TRACING) += trace.o
 wil6210-y += wil_platform.o
 wil6210-y += ethtool.o

drivers/net/wireless/ath/wil6210/debugfs.c

@@ -24,6 +24,7 @@
 #include "wil6210.h"
 #include "wmi.h"
 #include "txrx.h"
+#include "pmc.h"
 
 /* Nasty hack. Better have per device instances */
 static u32 mem_addr;
@@ -702,6 +703,89 @@ static const struct file_operations fops_back = {
 	.open  = simple_open,
 };
 
+/* pmc control, write:
+ * - "alloc <num descriptors> <descriptor_size>" to allocate PMC
+ * - "free" to release memory allocated for PMC
+ */
+static ssize_t wil_write_pmccfg(struct file *file, const char __user *buf,
+				size_t len, loff_t *ppos)
+{
+	struct wil6210_priv *wil = file->private_data;
+	int rc;
+	char *kbuf = kmalloc(len + 1, GFP_KERNEL);
+	char cmd[9];
+	int num_descs, desc_size;
+
+	if (!kbuf)
+		return -ENOMEM;
+
+	rc = simple_write_to_buffer(kbuf, len, ppos, buf, len);
+	if (rc != len) {
+		kfree(kbuf);
+		return rc >= 0 ? -EIO : rc;
+	}
+
+	kbuf[len] = '\0';
+	rc = sscanf(kbuf, "%8s %d %d", cmd, &num_descs, &desc_size);
+	kfree(kbuf);
+
+	if (rc < 0)
+		return rc;
+
+	if (rc < 1) {
+		wil_err(wil, "pmccfg: no params given\n");
+		return -EINVAL;
+	}
+
+	if (0 == strcmp(cmd, "alloc")) {
+		if (rc != 3) {
+			wil_err(wil, "pmccfg: alloc requires 2 params\n");
+			return -EINVAL;
+		}
+		wil_pmc_alloc(wil, num_descs, desc_size);
+	} else if (0 == strcmp(cmd, "free")) {
+		if (rc != 1) {
+			wil_err(wil, "pmccfg: free does not have any params\n");
+			return -EINVAL;
+		}
+		wil_pmc_free(wil, true);
+	} else {
+		wil_err(wil, "pmccfg: Unrecognized command \"%s\"\n", cmd);
+		return -EINVAL;
+	}
+
+	return len;
+}
+
+static ssize_t wil_read_pmccfg(struct file *file, char __user *user_buf,
+			       size_t count, loff_t *ppos)
+{
+	struct wil6210_priv *wil = file->private_data;
+	char text[256];
+	char help[] = "pmc control, write:\n"
+	" - \"alloc <num descriptors> <descriptor_size>\" to allocate pmc\n"
+	" - \"free\" to free memory allocated for pmc\n";
+
+	sprintf(text, "Last command status: %d\n\n%s",
+		wil_pmc_last_cmd_status(wil),
+		help);
+
+	return simple_read_from_buffer(user_buf, count, ppos, text,
+				       strlen(text) + 1);
+}
+
+static const struct file_operations fops_pmccfg = {
+	.read = wil_read_pmccfg,
+	.write = wil_write_pmccfg,
+	.open  = simple_open,
+};
+
+static const struct file_operations fops_pmcdata = {
+	.open		= simple_open,
+	.read		= wil_pmc_read,
+	.llseek		= wil_pmc_llseek,
+};
+
 /*---tx_mgmt---*/
 /* Write mgmt frame to this file to send it */
 static ssize_t wil_write_file_txmgmt(struct file *file, const char __user *buf,
@@ -1363,6 +1447,8 @@ static const struct {
 	{"tx_mgmt",		  S_IWUSR,	&fops_txmgmt},
 	{"wmi_send",		  S_IWUSR,	&fops_wmi},
 	{"back",	S_IRUGO | S_IWUSR,	&fops_back},
+	{"pmccfg",	S_IRUGO | S_IWUSR,	&fops_pmccfg},
+	{"pmcdata",	S_IRUGO,		&fops_pmcdata},
 	{"temp",	S_IRUGO,		&fops_temp},
 	{"freq",	S_IRUGO,		&fops_freq},
 	{"link",	S_IRUGO,		&fops_link},
@@ -1440,6 +1526,8 @@ int wil6210_debugfs_init(struct wil6210_priv *wil)
 	if (IS_ERR_OR_NULL(dbg))
 		return -ENODEV;
 
+	wil_pmc_init(wil);
+
 	wil6210_debugfs_init_files(wil, dbg);
 	wil6210_debugfs_init_isr(wil, dbg);
 	wil6210_debugfs_init_blobs(wil, dbg);
@@ -1459,4 +1547,9 @@ void wil6210_debugfs_remove(struct wil6210_priv *wil)
 {
 	debugfs_remove_recursive(wil->debug);
 	wil->debug = NULL;
+
+	/* free pmc memory without sending command to fw, as it will
+	 * be reset on the way down anyway
+	 */
+	wil_pmc_free(wil, false);
 }