[PATCH v2 09/18] drivers/fsi: scan slaves & register devices

From: christopher . lee . bostic
Date: Thu Jan 12 2017 - 17:30:40 EST


From: Jeremy Kerr <jk@xxxxxxxxxx>

Now that we have fsi_slave devices, scan each for endpoints, and
register them on the fsi bus.

Includes contributions from Chris Bostic <cbostic@xxxxxxxxxx>

Signed-off-by: Jeremy Kerr <jk@xxxxxxxxxx>
Signed-off-by: Chris Bostic <cbostic@xxxxxxxxxx>
---
drivers/fsi/fsi-core.c | 136 +++++++++++++++++++++++++++++++++++++++++++++++--
include/linux/fsi.h | 4 ++
2 files changed, 136 insertions(+), 4 deletions(-)

diff --git a/drivers/fsi/fsi-core.c b/drivers/fsi/fsi-core.c
index 931bcba..f7ef993 100644
--- a/drivers/fsi/fsi-core.c
+++ b/drivers/fsi/fsi-core.c
@@ -23,9 +23,19 @@
#include "fsi-master.h"

#define FSI_N_SLAVES 4
-#define FSI_SLAVE_CONF_CRC_SHIFT 4
-#define FSI_SLAVE_CONF_CRC_MASK 0x0000000f
-#define FSI_SLAVE_CONF_DATA_BITS 28
+
+#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_SLAVE_CONF_CRC_SHIFT 4
+#define FSI_SLAVE_CONF_CRC_MASK 0x0000000f
+#define FSI_SLAVE_CONF_DATA_BITS 28
+
+static const int engine_page_size = 0x400;

static DEFINE_IDA(master_ida);

@@ -38,8 +48,125 @@ 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;
+}
+
/* 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, crc;
+ 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;
+ }
+
+ crc = crc_fsi(0, conf >> FSI_SLAVE_CONF_CRC_SHIFT,
+ FSI_SLAVE_CONF_DATA_BITS);
+ if (crc != (conf & FSI_SLAVE_CONF_CRC_MASK)) {
+ 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->slave = slave;
+ 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)
{
struct fsi_slave *slave = to_fsi_slave(dev);
@@ -91,7 +218,8 @@ static int fsi_slave_init(struct fsi_master *master,
return rc;
}

- return rc;
+ fsi_slave_scan(slave);
+ return 0;
}

/* FSI master support */
diff --git a/include/linux/fsi.h b/include/linux/fsi.h
index 273cbf6..efa55ba 100644
--- a/include/linux/fsi.h
+++ b/include/linux/fsi.h
@@ -21,6 +21,10 @@ 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 {
--
1.8.2.2