FSI device driver introduction

new file mode 100644
index 0000000..3e45306
@@ -0,0 +1,38 @@
+/*
+ * FSI core driver
+ *
+ * Copyright (C) IBM Corporation 2016
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/device.h>
+#include <linux/fsi.h>
+#include <linux/module.h>
+
+/* FSI core & Linux bus type definitions */
+
+struct bus_type fsi_bus_type = {
+	.name		= "fsi",
+};
+EXPORT_SYMBOL_GPL(fsi_bus_type);
+
+static int fsi_init(void)
+{
+	return bus_register(&fsi_bus_type);
+}
+
+static void fsi_exit(void)
+{
+	bus_unregister(&fsi_bus_type);
+}
+
+module_init(fsi_init);
+module_exit(fsi_exit);

new file mode 100644
index 0000000..8e8bdea
@@ -0,0 +1,23 @@
+/*
+ * FSI device & driver interfaces
+ *
+ * Copyright (C) IBM Corporation 2016
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef LINUX_FSI_H
+#define LINUX_FSI_H
+
+#include <linux/device.h>
+
+extern struct bus_type fsi_bus_type;
+
+#endif /* LINUX_FSI_H */

index 8e8bdea..66dcf25 100644
@@ -18,6 +18,17 @@
 
 #include <linux/device.h>
 
+struct fsi_device {
+	struct device dev;
+};
+
+struct fsi_driver {
+	struct device_driver drv;
+};
+
+#define to_fsi_dev(devp) container_of(devp, struct fsi_device, dev)
+#define to_fsi_drv(drvp) container_of(drvp, struct fsi_driver, drv)
+
 extern struct bus_type fsi_bus_type;
 
 #endif /* LINUX_FSI_H */

index 3e45306..3d55bd5 100644
@@ -19,8 +19,29 @@
 
 /* FSI core & Linux bus type definitions */
 
+static int fsi_bus_match(struct device *dev, struct device_driver *drv)
+{
+	struct fsi_device *fsi_dev = to_fsi_dev(dev);
+	struct fsi_driver *fsi_drv = to_fsi_drv(drv);
+	const struct fsi_device_id *id;
+
+	if (!fsi_drv->id_table)
+		return 0;
+
+	for (id = fsi_drv->id_table; id->engine_type; id++) {
+		if (id->engine_type != fsi_dev->engine_type)
+			continue;
+		if (id->version == FSI_VERSION_ANY ||
+				id->version == fsi_dev->version)
+			return 1;
+	}
+
+	return 0;
+}
+
 struct bus_type fsi_bus_type = {
 	.name		= "fsi",
+	.match		= fsi_bus_match,
 };
 EXPORT_SYMBOL_GPL(fsi_bus_type);
 

index 66dcf25..6d843d4 100644
@@ -19,11 +19,28 @@
 #include <linux/device.h>
 
 struct fsi_device {
-	struct device dev;
+	struct device		dev;
+	u8			engine_type;
+	u8			version;
 };
 
+struct fsi_device_id {
+	u8	engine_type;
+	u8	version;
+};
+
+#define FSI_VERSION_ANY		0
+
+#define FSI_DEVICE(t) \
+	.engine_type = (t), .version = FSI_VERSION_ANY,
+
+#define FSI_DEVICE_VERSIONED(t, v) \
+	.engine_type = (t), .version = (v),
+
+
 struct fsi_driver {
-	struct device_driver drv;
+	struct device_driver		drv;
+	const struct fsi_device_id	*id_table;
 };
 
 #define to_fsi_dev(devp) container_of(devp, struct fsi_device, dev)

index 3d55bd5..ce9428d 100644
@@ -17,6 +17,26 @@
 #include <linux/fsi.h>
 #include <linux/module.h>
 
+#include "fsi-master.h"
+
+static atomic_t master_idx = ATOMIC_INIT(-1);
+
+/* FSI master support */
+
+int fsi_master_register(struct fsi_master *master)
+{
+	master->idx = atomic_inc_return(&master_idx);
+	get_device(master->dev);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(fsi_master_register);
+
+void fsi_master_unregister(struct fsi_master *master)
+{
+	put_device(master->dev);
+}
+EXPORT_SYMBOL_GPL(fsi_master_unregister);
+
 /* FSI core & Linux bus type definitions */
 
 static int fsi_bus_match(struct device *dev, struct device_driver *drv)

new file mode 100644
index 0000000..e75a810
@@ -0,0 +1,37 @@
+/*
+ * FSI master definitions. These comprise the core <--> master interface,
+ * to allow the core to interact with the (hardware-specific) masters.
+ *
+ * Copyright (C) IBM Corporation 2016
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef DRIVERS_FSI_MASTER_H
+#define DRIVERS_FSI_MASTER_H
+
+#include <linux/device.h>
+
+struct fsi_master {
+	struct device	*dev;
+	int		idx;
+	int		n_links;
+	int		(*read)(struct fsi_master *, int link,
+				uint8_t slave, uint32_t addr,
+				void *val, size_t size);
+	int		(*write)(struct fsi_master *, int link,
+				uint8_t slave, uint32_t addr,
+				const void *val, size_t size);
+};
+
+extern int fsi_master_register(struct fsi_master *master);
+extern void fsi_master_unregister(struct fsi_master *master);
+
+#endif /* DRIVERS_FSI_MASTER_H */

96 lines not on this page · raw message

index ce9428d..db1a1ce 100644
@@ -13,6 +13,8 @@
  * GNU General Public License for more details.
  */
 
+#define DEBUG
+
 #include <linux/device.h>
 #include <linux/fsi.h>
 #include <linux/module.h>

index db1a1ce..7df4291 100644
@@ -23,6 +23,15 @@
 
 static atomic_t master_idx = ATOMIC_INIT(-1);
 
+struct fsi_slave {
+	struct device		dev;
+	struct fsi_master	*master;
+	int			link;
+	uint8_t			id;
+};
+
+#define to_fsi_slave(d) container_of(d, struct fsi_slave, dev)
+
 /* FSI master support */
 
 int fsi_master_register(struct fsi_master *master)

index 7df4291..9744a55 100644
@@ -21,6 +21,8 @@
 
 #include "fsi-master.h"
 
+#define FSI_N_SLAVES	4
+
 static atomic_t master_idx = ATOMIC_INIT(-1);
 
 struct fsi_slave {

@@ -32,12 +34,34 @@ struct fsi_slave {
 
 #define to_fsi_slave(d) container_of(d, struct fsi_slave, dev)
 
+/* FSI slave support */
+static int fsi_slave_init(struct fsi_master *master,
+		int link, uint8_t slave_id)
+{
+	/* todo: initialise slave device, perform engine scan */
+
+	return -ENODEV;
+}
+
 /* FSI master support */
 
+static int fsi_master_scan(struct fsi_master *master)
+{
+	int link, slave_id;
+
+	for (link = 0; link < master->n_links; link++)
+		for (slave_id = 0; slave_id < FSI_N_SLAVES; slave_id++)
+			fsi_slave_init(master, link, slave_id);
+
+	return 0;
+
+}
+
 int fsi_master_register(struct fsi_master *master)
 {
 	master->idx = atomic_inc_return(&master_idx);
 	get_device(master->dev);
+	fsi_master_scan(master);
 	return 0;
 }
 EXPORT_SYMBOL_GPL(fsi_master_register);

index 9744a55..24538ae 100644
@@ -34,6 +34,29 @@ struct fsi_slave {
 
 #define to_fsi_slave(d) container_of(d, struct fsi_slave, dev)
 
+/* crc helpers */
+static const uint8_t crc4_tab[] = {
+	0x0, 0x7, 0xe, 0x9, 0xb, 0xc, 0x5, 0x2,
+	0x1, 0x6, 0xf, 0x8, 0xa, 0xd, 0x4, 0x3,
+};
+
+static uint8_t crc4(uint32_t x)
+{
+	uint8_t c = 0;
+	int i;
+
+	/* Calculate crc4 over four-bit nibbles, starting at the MSbit */
+	for (i = 28; i >= 0; i -= 4)
+		c = crc4_tab[c ^ ((x >> i) & 0xf)];
+
+	return c;
+}
+
+static bool check_crc4(uint32_t x)
+{
+	return crc4(x) == 0;
+}
+
 /* FSI slave support */
 static int fsi_slave_init(struct fsi_master *master,
 		int link, uint8_t slave_id)

index 24538ae..49a8e14 100644
@@ -18,6 +18,7 @@
 #include <linux/device.h>
 #include <linux/fsi.h>
 #include <linux/module.h>
+#include <linux/slab.h>
 
 #include "fsi-master.h"
 

@@ -58,12 +59,57 @@ static bool check_crc4(uint32_t x)
 }
 
 /* FSI slave support */
+
+static void fsi_slave_release(struct device *dev)
+{
+	struct fsi_slave *slave = to_fsi_slave(dev);
+	kfree(slave);
+}
+
 static int fsi_slave_init(struct fsi_master *master,
 		int link, uint8_t slave_id)
 {
-	/* todo: initialise slave device, perform engine scan */
+	struct fsi_slave *slave;
+	uint32_t chip_id;
+	int rc;
+
+	rc = master->read(master, link, slave_id, 0, &chip_id, sizeof(chip_id));
+	if (rc) {
+		dev_warn(master->dev, "can't read slave %02x:%02x: %d\n",
+				link, slave_id, rc);
+		return -ENODEV;
+	}
+
+	chip_id = be32_to_cpu(chip_id);
+	if (!check_crc4(chip_id)) {
+		dev_warn(master->dev, "slave %02x:%02x: invalid chip id CRC!\n",
+				link, slave_id);
+		return -EIO;
+	}
+
+	pr_debug("fsi: found chip %08x at %02x:%02x:%02x\n",
+			master->idx, chip_id, link, slave_id);
+
+	/* we can communicate with a slave; create devices and scan */
+	slave = kzalloc(sizeof(*slave), GFP_KERNEL);
+	if (!slave)
+		return -ENOMEM;
+
+	slave->master = master;
+	slave->id = slave_id;
+	slave->dev.parent = master->dev;
+	slave->dev.release = fsi_slave_release;
+
+	dev_set_name(&slave->dev, "slave@%02x:%02x", link, slave_id);
+	rc = device_register(&slave->dev);
+	if (rc < 0) {
+		dev_warn(master->dev, "failed to create slave device: %d\n",
+				rc);
+		put_device(&slave->dev);
+		return rc;
+	}
 
-	return -ENODEV;
+	return rc;
 }
 
 /* FSI master support */

index 49a8e14..63d26b5 100644
@@ -24,6 +24,16 @@
 
 #define FSI_N_SLAVES	4
 
+#define FSI_SLAVE_CONF_NEXT_MASK	0x80000000
+#define FSI_SLAVE_CONF_SLOTS_MASK	0x00ff0000
+#define FSI_SLAVE_CONF_SLOTS_SHIFT	16
+#define FSI_SLAVE_CONF_VERSION_MASK	0x0000f000
+#define FSI_SLAVE_CONF_VERSION_SHIFT	12
+#define FSI_SLAVE_CONF_TYPE_MASK	0x00000ff0
+#define FSI_SLAVE_CONF_TYPE_SHIFT	4
+
+static const int engine_page_size = 0x400;
+
 static atomic_t master_idx = ATOMIC_INIT(-1);
 
 struct fsi_slave {

@@ -35,6 +45,29 @@ struct fsi_slave {
 
 #define to_fsi_slave(d) container_of(d, struct fsi_slave, dev)
 
+/* FSI endpoint-device support */
+
+static void fsi_device_release(struct device *_device)
+{
+	struct fsi_device *device = to_fsi_dev(_device);
+	kfree(device);
+}
+
+static struct fsi_device *fsi_create_device(struct fsi_slave *slave)
+{
+	struct fsi_device *dev;
+
+	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
+	if (!dev)
+		return NULL;
+
+	dev->dev.parent = &slave->dev;
+	dev->dev.bus = &fsi_bus_type;
+	dev->dev.release = fsi_device_release;
+
+	return dev;
+}
+
 /* crc helpers */
 static const uint8_t crc4_tab[] = {
 	0x0, 0x7, 0xe, 0x9, 0xb, 0xc, 0x5, 0x2,

@@ -59,6 +92,95 @@ static bool check_crc4(uint32_t x)
 }
 
 /* FSI slave support */
+static int fsi_slave_read(struct fsi_slave *slave, uint32_t addr,
+		void *val, size_t size)
+{
+	return slave->master->read(slave->master, slave->link,
+			slave->id, addr, val, size);
+}
+
+static int fsi_slave_scan(struct fsi_slave *slave)
+{
+	uint32_t engine_addr;
+	uint32_t conf;
+	int rc, i;
+
+	/*
+	 * scan engines
+	 *
+	 * We keep the peek mode and slave engines for the core; so start
+	 * at the third slot in the configuration table. We also need to
+	 * skip the chip ID entry at the start of the address space.
+	 */
+	engine_addr = engine_page_size * 3;
+	for (i = 2; i < engine_page_size / sizeof(uint32_t); i++) {
+		uint8_t slots, version, type;
+		struct fsi_device *dev;
+
+		rc = fsi_slave_read(slave, (i + 1) * sizeof(conf),
+				&conf, sizeof(conf));
+		if (rc) {
+			dev_warn(&slave->dev,
+					"error reading slave registers\n");
+			return -1;
+		}
+
+		conf = be32_to_cpu(conf);
+
+		if (!check_crc4(conf)) {
+			dev_warn(&slave->dev,
+				"crc error in slave register at 0x%04x\n",
+					i);
+			return -1;
+		}
+
+		slots = (conf & FSI_SLAVE_CONF_SLOTS_MASK)
+			>> FSI_SLAVE_CONF_SLOTS_SHIFT;
+		version = (conf & FSI_SLAVE_CONF_VERSION_MASK)
+			>> FSI_SLAVE_CONF_VERSION_SHIFT;
+		type = (conf & FSI_SLAVE_CONF_TYPE_MASK)
+			>> FSI_SLAVE_CONF_TYPE_SHIFT;
+
+		/* Unused address areas are marked by a zero type value; this
+		 * skips the defined address areas */
+		if (type != 0) {
+
+			/* create device */
+			dev = fsi_create_device(slave);
+			if (!dev)
+				return -ENOMEM;
+
+			dev->engine_type = type;
+			dev->version = version;
+			dev->unit = i;
+			dev->addr = engine_addr;
+			dev->size = slots * engine_page_size;
+
+			dev_info(&slave->dev,
+			"engine[%i]: type %x, version %x, addr %x size %x\n",
+					dev->unit, dev->engine_type, version,
+					dev->addr, dev->size);
+
+			device_initialize(&dev->dev);
+			dev_set_name(&dev->dev, "%02x:%02x:%02x:%02x",
+					slave->master->idx, slave->link,
+					slave->id, i - 2);
+
+			rc = device_add(&dev->dev);
+			if (rc) {
+				dev_warn(&slave->dev, "add failed: %d\n", rc);
+				put_device(&dev->dev);
+			}
+		}
+
+		engine_addr += slots * engine_page_size;
+
+		if (!(conf & FSI_SLAVE_CONF_NEXT_MASK))
+			break;
+	}
+
+	return 0;
+}
 
 static void fsi_slave_release(struct device *dev)
 {

@@ -109,7 +231,8 @@ static int fsi_slave_init(struct fsi_master *master,
 		return rc;
 	}
 
-	return rc;
+	fsi_slave_scan(slave);
+	return 0;
 }
 
 /* FSI master support */

index 6d843d4..dfd3513 100644
@@ -22,6 +22,10 @@ struct fsi_device {
 	struct device		dev;
 	u8			engine_type;
 	u8			version;
+	u8			unit;
+	struct fsi_slave	*slave;
+	uint32_t		addr;
+	uint32_t		size;
 };
 
 struct fsi_device_id {

index 63d26b5..10bf817 100644
@@ -32,6 +32,8 @@
 #define FSI_SLAVE_CONF_TYPE_MASK	0x00000ff0
 #define FSI_SLAVE_CONF_TYPE_SHIFT	4
 
+#define FSI_PEEK_BASE			0x410
+
 static const int engine_page_size = 0x400;
 
 static atomic_t master_idx = ATOMIC_INIT(-1);

@@ -45,7 +47,42 @@ struct fsi_slave {
 
 #define to_fsi_slave(d) container_of(d, struct fsi_slave, dev)
 
+static int fsi_slave_read(struct fsi_slave *slave, uint32_t addr,
+		void *val, size_t size);
+static int fsi_slave_write(struct fsi_slave *slave, uint32_t addr,
+		const void *val, size_t size);
+
 /* FSI endpoint-device support */
+int fsi_device_read(struct fsi_device *dev, uint32_t addr, void *val,
+		size_t size)
+{
+	if (addr > dev->size)
+		return -EINVAL;
+
+	if (addr + size > dev->size)
+		return -EINVAL;
+
+	return fsi_slave_read(dev->slave, dev->addr + addr, val, size);
+}
+
+int fsi_device_write(struct fsi_device *dev, uint32_t addr, const void *val,
+		size_t size)
+{
+	if (addr > dev->size)
+		return -EINVAL;
+
+	if (addr + size > dev->size)
+		return -EINVAL;
+
+	return fsi_slave_write(dev->slave, dev->addr + addr, val, size);
+}
+
+int fsi_device_peek(struct fsi_device *dev, void *val)
+{
+	uint32_t addr = FSI_PEEK_BASE + ((dev->unit - 2) * sizeof(uint32_t));
+
+	return fsi_slave_read(dev->slave, addr, val, sizeof(uint32_t));
+}
 
 static void fsi_device_release(struct device *_device)
 {

@@ -99,6 +136,13 @@ static int fsi_slave_read(struct fsi_slave *slave, uint32_t addr,
 			slave->id, addr, val, size);
 }
 
+static int fsi_slave_write(struct fsi_slave *slave, uint32_t addr,
+		const void *val, size_t size)
+{
+	return slave->master->write(slave->master, slave->link,
+			slave->id, addr, val, size);
+}
+
 static int fsi_slave_scan(struct fsi_slave *slave)
 {
 	uint32_t engine_addr;

index dfd3513..47af0af 100644
@@ -28,6 +28,12 @@ struct fsi_device {
 	uint32_t		size;
 };
 
+extern int fsi_device_read(struct fsi_device *dev, uint32_t addr,
+		void *val, size_t size);
+extern int fsi_device_write(struct fsi_device *dev, uint32_t addr,
+		const void *val, size_t size);
+extern int fsi_device_peek(struct fsi_device *dev, void *val);
+
 struct fsi_device_id {
 	u8	engine_type;
 	u8	version;

@@ -41,7 +47,6 @@ struct fsi_device_id {
 #define FSI_DEVICE_VERSIONED(t, v) \
 	.engine_type = (t), .version = (v),
 
-
 struct fsi_driver {
 	struct device_driver		drv;
 	const struct fsi_device_id	*id_table;

92 lines not on this page · raw message

index 10bf817..a3a860a 100644
@@ -87,6 +87,7 @@ int fsi_device_peek(struct fsi_device *dev, void *val)
 static void fsi_device_release(struct device *_device)
 {
 	struct fsi_device *device = to_fsi_dev(_device);
+
 	kfree(device);
 }
 

@@ -185,8 +186,10 @@ static int fsi_slave_scan(struct fsi_slave *slave)
 		type = (conf & FSI_SLAVE_CONF_TYPE_MASK)
 			>> FSI_SLAVE_CONF_TYPE_SHIFT;
 
-		/* Unused address areas are marked by a zero type value; this
-		 * skips the defined address areas */
+		/*
+		 * Unused address areas are marked by a zero type value; this
+		 * skips the defined address areas
+		 */
 		if (type != 0) {
 
 			/* create device */

@@ -229,6 +232,7 @@ static int fsi_slave_scan(struct fsi_slave *slave)
 static void fsi_slave_release(struct device *dev)
 {
 	struct fsi_slave *slave = to_fsi_slave(dev);
+
 	kfree(slave);
 }
 

index 50aac0b..ec1ed5e 100644
@@ -93,4 +93,3 @@ static int __init fsi_master_fake_init(void)
 }
 
 module_init(fsi_master_fake_init);
-

index 3855829..5c3d5cd 100644
@@ -89,4 +89,3 @@ static struct platform_driver fsi_master_gpio_driver = {
 };
 
 module_platform_driver(fsi_master_gpio_driver);
-

new file mode 100644
index 0000000..ddb03cd
@@ -0,0 +1,63 @@
+/*
+ * FSI CFAM definitions
+ *
+ * Copyright (C) IBM Corporation 2016
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef DRIVERS_FSI_CFAM_H
+#define DRIVERS_FSI_CFAM_H
+
+#include <linux/device.h>
+
+#include "fsi-master.h"
+
+#define FSI_SLAVE_ENG_ID	2
+
+#define FSI_MAX_CFAMS_PER_LINK	4
+#define FSI_CFAM_SIZE		(FSI_LINK_SIZE / FSI_MAX_CFAMS_PER_LINK)
+#define FSI_PEEK_BASE		0x410
+#define FSI_SLAVE_BASE		0x800
+
+/* Config space decoding */
+#define FSI_CFG_NEXT_MASK	0x80000000
+#define FSI_CFG_SLOT_MASK	0x00ff0000
+#define FSI_CFG_SLOT_SHIFT	16
+#define FSI_CFG_VERS_MASK	0x0000f000
+#define FSI_CFG_VERS_SHIFT	12
+#define FSI_CFG_TYPE_MASK	0x00000ff0
+#define FSI_CFG_TYPE_SHIFT	4
+
+/*
+ * Return number of slots in the configuration word
+ */
+static inline uint8_t fsi_cfg_slot(uint32_t x)
+{
+	return (x & FSI_CFG_SLOT_MASK) >> FSI_CFG_SLOT_SHIFT;
+}
+
+/*
+ * Return version in the configuration word
+ */
+static inline uint8_t fsi_cfg_version(uint32_t x)
+{
+	return (x & FSI_CFG_VERS_MASK) >> FSI_CFG_VERS_SHIFT;
+}
+
+/*
+ * Return type field in the configuration word
+ */
+static inline uint8_t fsi_cfg_type(uint32_t x)
+{
+	return (x & FSI_CFG_TYPE_MASK) >> FSI_CFG_TYPE_SHIFT;
+}
+
+#endif /* DRIVERS_FSI_CFAM_H */

index a3a860a..0da8cf0 100644
@@ -21,19 +21,10 @@
 #include <linux/slab.h>
 
 #include "fsi-master.h"
+#include "fsi-cfam.h"
 
 #define FSI_N_SLAVES	4
 
-#define FSI_SLAVE_CONF_NEXT_MASK	0x80000000
-#define FSI_SLAVE_CONF_SLOTS_MASK	0x00ff0000
-#define FSI_SLAVE_CONF_SLOTS_SHIFT	16
-#define FSI_SLAVE_CONF_VERSION_MASK	0x0000f000
-#define FSI_SLAVE_CONF_VERSION_SHIFT	12
-#define FSI_SLAVE_CONF_TYPE_MASK	0x00000ff0
-#define FSI_SLAVE_CONF_TYPE_SHIFT	4
-
-#define FSI_PEEK_BASE			0x410
-
 static const int engine_page_size = 0x400;
 
 static atomic_t master_idx = ATOMIC_INIT(-1);

@@ -179,12 +170,9 @@ static int fsi_slave_scan(struct fsi_slave *slave)
 			return -1;
 		}
 
-		slots = (conf & FSI_SLAVE_CONF_SLOTS_MASK)
-			>> FSI_SLAVE_CONF_SLOTS_SHIFT;
-		version = (conf & FSI_SLAVE_CONF_VERSION_MASK)
-			>> FSI_SLAVE_CONF_VERSION_SHIFT;
-		type = (conf & FSI_SLAVE_CONF_TYPE_MASK)
-			>> FSI_SLAVE_CONF_TYPE_SHIFT;
+		slots = fsi_cfg_slot(conf);
+		version = fsi_cfg_version(conf);
+		type = fsi_cfg_type(conf);
 
 		/*
 		 * Unused address areas are marked by a zero type value; this

@@ -222,7 +210,7 @@ static int fsi_slave_scan(struct fsi_slave *slave)
 
 		engine_addr += slots * engine_page_size;
 
-		if (!(conf & FSI_SLAVE_CONF_NEXT_MASK))
+		if (!(conf & FSI_CFG_NEXT_MASK))
 			break;
 	}
 

index 0da8cf0..c5e7441 100644
@@ -22,6 +22,7 @@
 
 #include "fsi-master.h"
 #include "fsi-cfam.h"
+#include "fsi-slave.h"
 
 #define FSI_N_SLAVES	4
 

@@ -224,13 +225,66 @@ static void fsi_slave_release(struct device *dev)
 	kfree(slave);
 }
 
+/*
+ * Issue a break commad on this link
+ */
+static int fsi_master_break(struct fsi_master *master, int link)
+{
+	int rc = 0;
+
+	if (master->send_break)
+		rc = master->send_break(master, link);
+
+	return rc;
+}
+
+static void set_smode_defaults(struct fsi_master *master, uint32_t *smode)
+{
+	*smode = FSI_SMODE_WSC | FSI_SMODE_ECRC
+		| fsi_smode_echodly(0xf) | fsi_smode_senddly(0xf)
+		| fsi_smode_lbcrr(1) | fsi_smode_sid(0);
+}
+
+static int fsi_master_set_smode(struct fsi_master *master, int link)
+{
+	uint32_t smode;
+	int rc;
+
+	set_smode_defaults(master, &smode);
+	rc = master->write(master, link, 0, FSI_SLAVE_BASE + FSI_SMODE,
+			&smode, sizeof(smode));
+
+	return rc;
+}
+
 static int fsi_slave_init(struct fsi_master *master,
 		int link, uint8_t slave_id)
 {
-	struct fsi_slave *slave;
+	struct fsi_slave *slave = NULL;
 	uint32_t chip_id;
 	int rc;
 
+	/*
+	 * todo: Due to CFAM hardware issues related to BREAK commands we're
+	 * limited to only one CFAM per link. Once hardware fixes are available
+	 * this restriction can be removed.
+	 */
+	if (slave_id > 0)
+		return 0;
+
+	rc = fsi_master_break(master, link);
+	if (rc) {
+		dev_warn(master->dev, "no slave detected at %02x:%02x\n",
+				link, slave_id);
+		return -ENODEV;
+	}
+
+	rc = fsi_master_set_smode(master, link);
+	if (rc) {
+		dev_warn(master->dev, "failed to set smode id, rc:%d\n", rc);
+		return -ENODEV;
+	}
+
 	rc = master->read(master, link, slave_id, 0, &chip_id, sizeof(chip_id));
 	if (rc) {
 		dev_warn(master->dev, "can't read slave %02x:%02x: %d\n",

@@ -273,13 +327,28 @@ static int fsi_slave_init(struct fsi_master *master,
 
 /* FSI master support */
 
+static int fsi_master_link_enable(struct fsi_master *master, int link)
+{
+	int rc;
+
+	if (master->link_enable)
+		rc = master->link_enable(master, link);
+
+	return rc;
+}
+
 static int fsi_master_scan(struct fsi_master *master)
 {
-	int link, slave_id;
+	int link, slave_id, rc;
+
+	for (link = 0; link < master->n_links; link++) {
+		rc = fsi_master_link_enable(master, link);
+		if (rc)
+			continue;
 
-	for (link = 0; link < master->n_links; link++)
 		for (slave_id = 0; slave_id < FSI_N_SLAVES; slave_id++)
 			fsi_slave_init(master, link, slave_id);
+	}
 
 	return 0;
 

index ec1ed5e..c7ad631 100644
@@ -63,6 +63,8 @@ static int fsi_master_fake_probe(struct platform_device *pdev)
 	master->n_links = 1;
 	master->read = fsi_master_fake_read;
 	master->write = fsi_master_fake_write;
+	master->send_break = NULL;
+	master->link_enable = NULL;
 
 	return fsi_master_register(master);
 }

index 5c3d5cd..166370a 100644
@@ -7,6 +7,8 @@
 #include <linux/module.h>
 
 #include "fsi-master.h"
+#include "fsi-cfam.h"
+#include "fsi-slave.h"
 
 struct fsi_master_gpio {
 	struct fsi_master	master;

@@ -50,6 +52,35 @@ static int fsi_master_gpio_write(struct fsi_master *_master, int link,
 	return 0;
 }
 
+/*
+ * Issue a break command on link
+ */
+static int fsi_master_gpio_break(struct fsi_master *_master, int link)
+{
+	struct fsi_master_gpio *master = to_fsi_master_gpio(_master);
+
+	if (link != 0)
+		return -ENODEV;
+
+	/* todo: send the break pattern over gpio */
+	(void)master;
+
+	return 0;
+}
+
+static int fsi_master_gpio_link_enable(struct fsi_master *_master, int link)
+{
+	struct fsi_master_gpio *master = to_fsi_master_gpio(_master);
+
+	if (link != 0)
+		return -ENODEV;
+
+	/* todo: set the enable pin */
+	(void)master;
+
+	return 0;
+}
+
 static int fsi_master_gpio_probe(struct platform_device *pdev)
 {
 	struct fsi_master_gpio *master;

@@ -71,6 +102,8 @@ static int fsi_master_gpio_probe(struct platform_device *pdev)
 
 	master->master.read = fsi_master_gpio_read;
 	master->master.write = fsi_master_gpio_write;
+	master->master.send_break = fsi_master_gpio_break;
+	master->master.link_enable = fsi_master_gpio_link_enable;
 
 	return fsi_master_register(&master->master);
 }

index e75a810..94a0671 100644
@@ -29,6 +29,8 @@ struct fsi_master {
 	int		(*write)(struct fsi_master *, int link,
 				uint8_t slave, uint32_t addr,
 				const void *val, size_t size);
+	int		(*send_break)(struct fsi_master *, int link);
+	int		(*link_enable)(struct fsi_master *, int link);
 };
 
 extern int fsi_master_register(struct fsi_master *master);

62 lines not on this page · raw message

index 166370a..fe757cc 100644
@@ -5,15 +5,52 @@
 #include <linux/platform_device.h>
 #include <linux/gpio/consumer.h>
 #include <linux/module.h>
+#include <linux/delay.h>
 
 #include "fsi-master.h"
 #include "fsi-cfam.h"
 #include "fsi-slave.h"
 
+#define FSI_ECHO_DELAY_CLOCKS	16	/* Number clocks for echo delay */
+#define FSI_PRE_BREAK_CLOCKS	50	/* Number clocks to prep for break */
+#define FSI_BREAK_CLOCKS	256	/* Number of clocks to issue break */
+#define FSI_POST_BREAK_CLOCKS	16000	/* Number clocks to set up cfam */
+#define FSI_INIT_CLOCKS		5000	/* Clear out any old data and states */
+
+#define FSI_GPIO_STD_DELAY	10	/* Standard GPIO delay in nS */
+					/* todo: adjust down as low as */
+					/* possible or eliminate */
+
+#define FSI_GPIO_CMD_DPOLL	0x0000808A
+#define FSI_GPIO_CMD_DPOLL_SIZE	10
+#define FSI_GPIO_DPOLL_CLOCKS	24	/* < 21 will cause slave to hang */
+#define FSI_GPIO_CMD_DEFAULT	0x2000000000000000ULL
+#define FSI_GPIO_CMD_WRITE	0
+#define FSI_GPIO_CMD_READ	0x0400000000000000ULL
+#define FSI_GPIO_CMD_SLAVE_MASK	0xC000000000000000ULL
+#define FSI_GPIO_CMD_ADDR_SHIFT	3
+#define FSI_GPIO_CMD_SIZE_16	0x0000001000000000ULL
+#define FSI_GPIO_CMD_SIZE_32	0x0000003000000000ULL
+#define FSI_GPIO_CMD_DATA_SHIFT	28
+#define FSI_GPIO_CMD_DFLT_LEN	32
+#define FSI_GPIO_RESP_BUSY	1
+#define FSI_GPIO_RESP_ERRA	2
+#define FSI_GPIO_RESP_ERRC	3
+#define FSI_GPIO_RESP_ACK	0
+#define FSI_GPIO_RESP_ACKD	4
+#define FSI_GPIO_MAX_BUSY	100
+#define FSI_GPIO_MTOE_COUNT	1000
+#define FSI_GPIO_MTOE		1
+#define FSI_GPIO_DRAIN_BITS	20
+#define FSI_GPIO_CRC_SIZE	4
+
 struct fsi_master_gpio {
 	struct fsi_master	master;
 	struct gpio_desc	*gpio_clk;
 	struct gpio_desc	*gpio_data;
+	struct gpio_desc	*gpio_trans;		/* Voltage translator */
+	struct gpio_desc	*gpio_enable;		/* FSI enable */
+	struct gpio_desc	*gpio_mux;		/* Mux control */
 };
 
 #define to_fsi_master_gpio(m) container_of(m, struct fsi_master_gpio, master)

@@ -23,33 +60,287 @@ struct fsi_gpio_msg {
 	uint8_t		bits;
 };
 
+static void add_crc(struct fsi_gpio_msg *cmd)
+{
+
+}
+
+static void set_clock(struct fsi_master_gpio *master)
+{
+	/* This delay is required - do not remove */
+	ndelay(FSI_GPIO_STD_DELAY);
+	gpiod_set_value(master->gpio_clk, 1);
+}
+
+static void clear_clock(struct fsi_master_gpio *master)
+{
+	/* This delay is required - do not remove */
+	ndelay(FSI_GPIO_STD_DELAY);
+	gpiod_set_value(master->gpio_clk, 0);
+}
+
+static void clock_toggle(struct fsi_master_gpio *master, int count)
+{
+	int i;
+
+	for (i = 0; i < count; i++) {
+		clear_clock(master);
+		set_clock(master);
+	}
+}
+
+static int sda_in(struct fsi_master_gpio *master)
+{
+	return gpiod_get_value(master->gpio_data);
+}
+
+static void sda_out(struct fsi_master_gpio *master, int value)
+{
+	gpiod_set_value(master->gpio_data, value);
+
+	/* Required -do not remove */
+	ndelay(FSI_GPIO_STD_DELAY);
+}
+
+static void set_sda_input(struct fsi_master_gpio *master)
+{
+	gpiod_direction_input(master->gpio_data);
+	gpiod_direction_output(master->gpio_trans, 0);
+}
+
+static void set_sda_output(struct fsi_master_gpio *master,
+			   int value)
+{
+	gpiod_direction_output(master->gpio_data, value);
+	gpiod_direction_output(master->gpio_trans, 1);
+}
+
+static void serial_in(struct fsi_master_gpio *master, struct fsi_gpio_msg *cmd)
+{
+	uint8_t bit;
+	uint64_t msg = 0;
+	uint8_t in_bit = 0;
+
+	set_sda_input(master);
+
+	for (bit = 0; bit < cmd->bits; bit++) {
+		clock_toggle(master, 1);
+		in_bit = sda_in(master);
+		msg |= in_bit;
+		msg <<= 1;
+	}
+	cmd->msg = ~msg;		/*  Data is negative active */
+}
+
+static void serial_out(struct fsi_master_gpio *master, struct fsi_gpio_msg *cmd)
+{
+	uint8_t bit;
+	uint64_t msg = ~cmd->msg;	/* Data is negative active */
+	uint64_t sda_mask = 1;
+	uint64_t last_bit = ~0;
+
+	set_sda_output(master, 0);
+
+	/* Send the start bit */
+	sda_out(master, 1);
+	clock_toggle(master, 1);
+
+	/* Send the message */
+	for (bit = 0; bit < cmd->bits; bit++) {
+		if (last_bit ^ (msg & sda_mask)) {
+			sda_out(master, msg & sda_mask);
+			last_bit = msg & sda_mask;
+		}
+		clock_toggle(master, 1);
+		msg >>= 1;
+	}
+}
+
+/*
+ * Clock out some 0's after every message to ride out line reflections
+ */
+static void echo_delay(struct fsi_master_gpio *master)
+{
+	set_sda_output(master, 0);
+	clock_toggle(master, FSI_ECHO_DELAY_CLOCKS);
+}
+
+/*
+ * Used in bus error cases only.  Clears out any remaining data the slave
+ * is attempting to send
+ */
+static void drain_response(struct fsi_master_gpio *master)
+{
+	struct fsi_gpio_msg msg;
+
+	msg.bits = FSI_GPIO_DRAIN_BITS;
+	serial_in(master, &msg);
+}
+
+/*
+ * Store information on master errors so handler can detect and clean
+ * up the bus
+ */
+static void fsi_master_gpio_error(struct fsi_master_gpio *master, int error)
+{
+
+}
+
+static int poll_for_response(struct fsi_master_gpio *master, uint8_t expected,
+			uint8_t size, void *data)
+{
+	int busy_count = 0, i;
+	struct fsi_gpio_msg response, cmd;
+	int bits_remaining = 0;
+
+	do {
+		response.msg = 0;
+		response.bits = 1;
+		for (i = 0; i < FSI_GPIO_MTOE_COUNT; i++) {
+			serial_in(master, &response);
+			if (response.msg)
+				break;
+		}
+		if (unlikely(i >= FSI_GPIO_MTOE_COUNT)) {
+			dev_info(master->master.dev,
+				"Master time out waiting for response\n");
+			drain_response(master);
+			fsi_master_gpio_error(master, FSI_GPIO_MTOE);
+			return FSI_GPIO_MTOE;
+		}
+
+		/* Response received */
+		response.msg = 0;
+		response.bits = 2;
+		serial_in(master, &response);
+		dev_info(master->master.dev, "cfam id:%d\n", (int)response.msg);
+
+		response.msg = 0;
+		response.bits = 2;
+		serial_in(master, &response);
+		dev_info(master->master.dev, "response id:%d\n",
+							(int)response.msg);
+
+		switch (response.msg) {
+		case FSI_GPIO_RESP_ACK:
+			if (expected == FSI_GPIO_RESP_ACKD)
+				bits_remaining = 8 * sizeof(size);
+			break;
+
+		case FSI_GPIO_RESP_BUSY:
+			/*
+			 * Its necessary to clock slave before issuing
+			 * d-poll, not indicated in the hardware protocol
+			 * spec. < 20 clocks causes slave to hang, 21 ok.
+			 */
+			set_sda_output(master, 0);
+			clock_toggle(master, FSI_GPIO_DPOLL_CLOCKS);
+			cmd.msg = FSI_GPIO_CMD_DPOLL;
+			cmd.bits = FSI_GPIO_CMD_DPOLL_SIZE;
+			serial_out(master, &cmd);
+			continue;
+
+		case FSI_GPIO_RESP_ERRA:
+		case FSI_GPIO_RESP_ERRC:
+			dev_info(master->master.dev, "ERR received: %d\n",
+				(int)response.msg);
+			drain_response(master);
+			fsi_master_gpio_error(master, response.msg);
+			return response.msg;
+		}
+
+		/* Read in the data field if applicable */
+		if (bits_remaining) {
+			response.msg = 0;
+			response.bits = bits_remaining;
+			serial_in(master, &response);
+		}
+
+		/* Read in the crc and check it */
+		response.msg = 0;
+		response.bits = FSI_GPIO_CRC_SIZE;
+		serial_in(master, &response);
+
+		/* todo: verify crc is correct, flag error if not */
+
+		return 0;
+
+	} while (busy_count++ < FSI_GPIO_MAX_BUSY);
+
+	return busy_count;
+}
+
+static void build_command(struct fsi_gpio_msg *cmd, uint64_t mode,
+			uint8_t slave, uint32_t addr, size_t size,
+			const void *data)
+{
+	cmd->bits = FSI_GPIO_CMD_DFLT_LEN;
+	cmd->msg = FSI_GPIO_CMD_DEFAULT;
+	cmd->msg |= mode;
+
+	/* todo: handle more than just slave id 0 */
+	cmd->msg &= ~FSI_GPIO_CMD_SLAVE_MASK;
+
+	cmd->msg |= (addr << FSI_GPIO_CMD_ADDR_SHIFT);
+	if (size == sizeof(uint8_t)) {
+		if (data)
+			cmd->msg |=
+				*((uint8_t *)data) >> FSI_GPIO_CMD_DATA_SHIFT;
+	} else if (size == sizeof(uint16_t)) {
+		cmd->msg |= FSI_GPIO_CMD_SIZE_16;
+		if (data)
+			cmd->msg |=
+				*((uint16_t *)data) >> FSI_GPIO_CMD_DATA_SHIFT;
+	} else {
+		cmd->msg |= FSI_GPIO_CMD_SIZE_32;
+		if (data)
+			cmd->msg |=
+				*((uint32_t *)data) >> FSI_GPIO_CMD_DATA_SHIFT;
+	}
+	if (mode == FSI_GPIO_CMD_WRITE)
+		cmd->bits += (8 * size);
+
+	add_crc(cmd);
+}
+
 static int fsi_master_gpio_read(struct fsi_master *_master, int link,
 		uint8_t slave, uint32_t addr, void *val, size_t size)
 {
 	struct fsi_master_gpio *master = to_fsi_master_gpio(_master);
+	struct fsi_gpio_msg cmd;
+	int rc;
 
 	if (link != 0)
 		return -ENODEV;
 
-	/* todo: format read into a message, send, poll for response */
-	(void)master;
+	/* Send the command */
+	build_command(&cmd, FSI_GPIO_CMD_READ, slave, addr, size, NULL);
+	serial_out(master, &cmd);
+	echo_delay(master);
 
+	rc = poll_for_response(master, FSI_GPIO_RESP_ACKD, size, val);
 
-	return 0;
+	return rc;
 }
 
 static int fsi_master_gpio_write(struct fsi_master *_master, int link,
 		uint8_t slave, uint32_t addr, const void *val, size_t size)
 {
+	int rc;
 	struct fsi_master_gpio *master = to_fsi_master_gpio(_master);
+	struct fsi_gpio_msg cmd;
 
 	if (link != 0)
 		return -ENODEV;
 
-	/* todo: format write into a message, send, poll for response */
-	(void)master;
+	/* Send the command */
+	build_command(&cmd, FSI_GPIO_CMD_WRITE, slave, addr, size, val);
+	serial_out(master, &cmd);
+	echo_delay(master);
 
-	return 0;
+	rc = poll_for_response(master, FSI_GPIO_RESP_ACK, size, NULL);
+
+	return rc;
 }
 
 /*

@@ -58,14 +349,40 @@ static int fsi_master_gpio_write(struct fsi_master *_master, int link,
 static int fsi_master_gpio_break(struct fsi_master *_master, int link)
 {
 	struct fsi_master_gpio *master = to_fsi_master_gpio(_master);
+	uint32_t smode;
+	int rc;
 
 	if (link != 0)
 		return -ENODEV;
 
-	/* todo: send the break pattern over gpio */
-	(void)master;
+	set_sda_output(master, 0);
+	clock_toggle(master, FSI_PRE_BREAK_CLOCKS);
 
-	return 0;
+	sda_out(master, 1);
+	clock_toggle(master, FSI_BREAK_CLOCKS);
+
+	echo_delay(master);
+
+	sda_out(master, 0);
+	clock_toggle(master, FSI_POST_BREAK_CLOCKS);
+
+	udelay(200);		/* wait for logic reset to take effect */
+	rc = _master->read(_master, link, 3, FSI_SLAVE_BASE + FSI_SMODE,
+			&smode, sizeof(smode));
+	dev_info(_master->dev, "smode after break:%08x rc:%d\n", smode, rc);
+
+	return rc;
+}
+
+static void fsi_master_gpio_init(struct fsi_master_gpio *master)
+{
+	gpiod_direction_output(master->gpio_mux, 1);
+	gpiod_direction_output(master->gpio_clk, 1);
+	set_sda_output(master, 1);
+	gpiod_direction_output(master->gpio_enable, 0);
+
+	/* todo: evaluate if clocks can be reduced */
+	clock_toggle(master, FSI_INIT_CLOCKS);
 }
 
 static int fsi_master_gpio_link_enable(struct fsi_master *_master, int link)

@@ -75,8 +392,7 @@ static int fsi_master_gpio_link_enable(struct fsi_master *_master, int link)
 	if (link != 0)
 		return -ENODEV;
 
-	/* todo: set the enable pin */
-	(void)master;
+	gpiod_set_value(master->gpio_enable, 1);
 
 	return 0;
 }

@@ -100,11 +416,28 @@ static int fsi_master_gpio_probe(struct platform_device *pdev)
 		return PTR_ERR(gpio);
 	master->gpio_data = gpio;
 
+	gpio = devm_gpiod_get(&pdev->dev, "trans", 0);
+	if (IS_ERR(gpio))
+		return PTR_ERR(gpio);
+	master->gpio_trans = gpio;
+
+	gpio = devm_gpiod_get(&pdev->dev, "enable", 0);
+	if (IS_ERR(gpio))
+		return PTR_ERR(gpio);
+	master->gpio_enable = gpio;
+
+	gpio = devm_gpiod_get(&pdev->dev, "mux", 0);
+	if (IS_ERR(gpio))
+		return PTR_ERR(gpio);
+	master->gpio_mux = gpio;
+
 	master->master.read = fsi_master_gpio_read;
 	master->master.write = fsi_master_gpio_write;
 	master->master.send_break = fsi_master_gpio_break;
 	master->master.link_enable = fsi_master_gpio_link_enable;
 
+	fsi_master_gpio_init(master);
+
 	return fsi_master_register(&master->master);
 }
 

index c5e7441..15d8635 100644
@@ -391,6 +391,27 @@ static int fsi_bus_match(struct device *dev, struct device_driver *drv)
 	return 0;
 }
 
+int fsidrv_register(struct fsi_driver *fsi_drv)
+{
+	int rc = 0;
+
+	if (!fsi_drv)
+		return -EINVAL;
+	if (!fsi_drv->id_table)
+		return -EINVAL;
+
+	rc = driver_register(&fsi_drv->drv);
+
+	return rc;
+}
+EXPORT_SYMBOL_GPL(fsidrv_register);
+
+void fsidrv_unregister(struct fsi_driver *fsi_drv)
+{
+	driver_unregister(&fsi_drv->drv);
+}
+EXPORT_SYMBOL_GPL(fsidrv_unregister);
+
 struct bus_type fsi_bus_type = {
 	.name		= "fsi",
 	.match		= fsi_bus_match,

62 lines not on this page · raw message

index 47af0af..09670b7 100644
@@ -55,6 +55,9 @@ struct fsi_driver {
 #define to_fsi_dev(devp) container_of(devp, struct fsi_device, dev)
 #define to_fsi_drv(drvp) container_of(drvp, struct fsi_driver, drv)
 
+extern int fsidrv_register(struct fsi_driver *);
+extern void fsidrv_unregister(struct fsi_driver *);
+
 extern struct bus_type fsi_bus_type;
 
 #endif /* LINUX_FSI_H */