294 lines
7.3 KiB
C
294 lines
7.3 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
/*
|
|
* FSI hub master driver
|
|
*
|
|
* Copyright (C) IBM Corporation 2016
|
|
*/
|
|
|
|
#include <linux/delay.h>
|
|
#include <linux/fsi.h>
|
|
#include <linux/module.h>
|
|
#include <linux/of.h>
|
|
#include <linux/slab.h>
|
|
|
|
#include "fsi-master.h"
|
|
|
|
#define FSI_ENGID_HUB_MASTER 0x1c
|
|
|
|
#define FSI_LINK_ENABLE_SETUP_TIME 10 /* in mS */
|
|
|
|
/*
|
|
* FSI hub master support
|
|
*
|
|
* A hub master increases the number of potential target devices that the
|
|
* primary FSI master can access. For each link a primary master supports,
|
|
* each of those links can in turn be chained to a hub master with multiple
|
|
* links of its own.
|
|
*
|
|
* The hub is controlled by a set of control registers exposed as a regular fsi
|
|
* device (the hub->upstream device), and provides access to the downstream FSI
|
|
* bus as through an address range on the slave itself (->addr and ->size).
|
|
*
|
|
* [This differs from "cascaded" masters, which expose the entire downstream
|
|
* bus entirely through the fsi device address range, and so have a smaller
|
|
* accessible address space.]
|
|
*/
|
|
struct fsi_master_hub {
|
|
struct fsi_master master;
|
|
struct fsi_device *upstream;
|
|
uint32_t addr, size; /* slave-relative addr of */
|
|
/* master address space */
|
|
};
|
|
|
|
#define to_fsi_master_hub(m) container_of(m, struct fsi_master_hub, master)
|
|
|
|
static int hub_master_read(struct fsi_master *master, int link,
|
|
uint8_t id, uint32_t addr, void *val, size_t size)
|
|
{
|
|
struct fsi_master_hub *hub = to_fsi_master_hub(master);
|
|
|
|
if (id != 0)
|
|
return -EINVAL;
|
|
|
|
addr += hub->addr + (link * FSI_HUB_LINK_SIZE);
|
|
return fsi_slave_read(hub->upstream->slave, addr, val, size);
|
|
}
|
|
|
|
static int hub_master_write(struct fsi_master *master, int link,
|
|
uint8_t id, uint32_t addr, const void *val, size_t size)
|
|
{
|
|
struct fsi_master_hub *hub = to_fsi_master_hub(master);
|
|
|
|
if (id != 0)
|
|
return -EINVAL;
|
|
|
|
addr += hub->addr + (link * FSI_HUB_LINK_SIZE);
|
|
return fsi_slave_write(hub->upstream->slave, addr, val, size);
|
|
}
|
|
|
|
static int hub_master_break(struct fsi_master *master, int link)
|
|
{
|
|
uint32_t addr;
|
|
__be32 cmd;
|
|
|
|
addr = 0x4;
|
|
cmd = cpu_to_be32(0xc0de0000);
|
|
|
|
return hub_master_write(master, link, 0, addr, &cmd, sizeof(cmd));
|
|
}
|
|
|
|
static int hub_master_link_enable(struct fsi_master *master, int link)
|
|
{
|
|
struct fsi_master_hub *hub = to_fsi_master_hub(master);
|
|
int idx, bit;
|
|
__be32 reg;
|
|
int rc;
|
|
|
|
idx = link / 32;
|
|
bit = link % 32;
|
|
|
|
reg = cpu_to_be32(0x80000000 >> bit);
|
|
|
|
rc = fsi_device_write(hub->upstream, FSI_MSENP0 + (4 * idx), ®, 4);
|
|
|
|
mdelay(FSI_LINK_ENABLE_SETUP_TIME);
|
|
|
|
fsi_device_read(hub->upstream, FSI_MENP0 + (4 * idx), ®, 4);
|
|
|
|
return rc;
|
|
}
|
|
|
|
static void hub_master_release(struct device *dev)
|
|
{
|
|
struct fsi_master_hub *hub = to_fsi_master_hub(dev_to_fsi_master(dev));
|
|
|
|
kfree(hub);
|
|
}
|
|
|
|
/* mmode encoders */
|
|
static inline u32 fsi_mmode_crs0(u32 x)
|
|
{
|
|
return (x & FSI_MMODE_CRS0MASK) << FSI_MMODE_CRS0SHFT;
|
|
}
|
|
|
|
static inline u32 fsi_mmode_crs1(u32 x)
|
|
{
|
|
return (x & FSI_MMODE_CRS1MASK) << FSI_MMODE_CRS1SHFT;
|
|
}
|
|
|
|
static int hub_master_init(struct fsi_master_hub *hub)
|
|
{
|
|
struct fsi_device *dev = hub->upstream;
|
|
__be32 reg;
|
|
int rc;
|
|
|
|
reg = cpu_to_be32(FSI_MRESP_RST_ALL_MASTER | FSI_MRESP_RST_ALL_LINK
|
|
| FSI_MRESP_RST_MCR | FSI_MRESP_RST_PYE);
|
|
rc = fsi_device_write(dev, FSI_MRESP0, ®, sizeof(reg));
|
|
if (rc)
|
|
return rc;
|
|
|
|
/* Initialize the MFSI (hub master) engine */
|
|
reg = cpu_to_be32(FSI_MRESP_RST_ALL_MASTER | FSI_MRESP_RST_ALL_LINK
|
|
| FSI_MRESP_RST_MCR | FSI_MRESP_RST_PYE);
|
|
rc = fsi_device_write(dev, FSI_MRESP0, ®, sizeof(reg));
|
|
if (rc)
|
|
return rc;
|
|
|
|
reg = cpu_to_be32(FSI_MECTRL_EOAE | FSI_MECTRL_P8_AUTO_TERM);
|
|
rc = fsi_device_write(dev, FSI_MECTRL, ®, sizeof(reg));
|
|
if (rc)
|
|
return rc;
|
|
|
|
reg = cpu_to_be32(FSI_MMODE_EIP | FSI_MMODE_ECRC | FSI_MMODE_EPC
|
|
| fsi_mmode_crs0(1) | fsi_mmode_crs1(1)
|
|
| FSI_MMODE_P8_TO_LSB);
|
|
rc = fsi_device_write(dev, FSI_MMODE, ®, sizeof(reg));
|
|
if (rc)
|
|
return rc;
|
|
|
|
reg = cpu_to_be32(0xffff0000);
|
|
rc = fsi_device_write(dev, FSI_MDLYR, ®, sizeof(reg));
|
|
if (rc)
|
|
return rc;
|
|
|
|
reg = cpu_to_be32(~0);
|
|
rc = fsi_device_write(dev, FSI_MSENP0, ®, sizeof(reg));
|
|
if (rc)
|
|
return rc;
|
|
|
|
/* Leave enabled long enough for master logic to set up */
|
|
mdelay(FSI_LINK_ENABLE_SETUP_TIME);
|
|
|
|
rc = fsi_device_write(dev, FSI_MCENP0, ®, sizeof(reg));
|
|
if (rc)
|
|
return rc;
|
|
|
|
rc = fsi_device_read(dev, FSI_MAEB, ®, sizeof(reg));
|
|
if (rc)
|
|
return rc;
|
|
|
|
reg = cpu_to_be32(FSI_MRESP_RST_ALL_MASTER | FSI_MRESP_RST_ALL_LINK);
|
|
rc = fsi_device_write(dev, FSI_MRESP0, ®, sizeof(reg));
|
|
if (rc)
|
|
return rc;
|
|
|
|
rc = fsi_device_read(dev, FSI_MLEVP0, ®, sizeof(reg));
|
|
if (rc)
|
|
return rc;
|
|
|
|
/* Reset the master bridge */
|
|
reg = cpu_to_be32(FSI_MRESB_RST_GEN);
|
|
rc = fsi_device_write(dev, FSI_MRESB0, ®, sizeof(reg));
|
|
if (rc)
|
|
return rc;
|
|
|
|
reg = cpu_to_be32(FSI_MRESB_RST_ERR);
|
|
return fsi_device_write(dev, FSI_MRESB0, ®, sizeof(reg));
|
|
}
|
|
|
|
static int hub_master_probe(struct device *dev)
|
|
{
|
|
struct fsi_device *fsi_dev = to_fsi_dev(dev);
|
|
struct fsi_master_hub *hub;
|
|
uint32_t reg, links;
|
|
__be32 __reg;
|
|
int rc;
|
|
|
|
rc = fsi_device_read(fsi_dev, FSI_MVER, &__reg, sizeof(__reg));
|
|
if (rc)
|
|
return rc;
|
|
|
|
reg = be32_to_cpu(__reg);
|
|
links = (reg >> 8) & 0xff;
|
|
dev_dbg(dev, "hub version %08x (%d links)\n", reg, links);
|
|
|
|
rc = fsi_slave_claim_range(fsi_dev->slave, FSI_HUB_LINK_OFFSET,
|
|
FSI_HUB_LINK_SIZE * links);
|
|
if (rc) {
|
|
dev_err(dev, "can't claim slave address range for links");
|
|
return rc;
|
|
}
|
|
|
|
hub = kzalloc(sizeof(*hub), GFP_KERNEL);
|
|
if (!hub) {
|
|
rc = -ENOMEM;
|
|
goto err_release;
|
|
}
|
|
|
|
hub->addr = FSI_HUB_LINK_OFFSET;
|
|
hub->size = FSI_HUB_LINK_SIZE * links;
|
|
hub->upstream = fsi_dev;
|
|
|
|
hub->master.dev.parent = dev;
|
|
hub->master.dev.release = hub_master_release;
|
|
hub->master.dev.of_node = of_node_get(dev_of_node(dev));
|
|
|
|
hub->master.n_links = links;
|
|
hub->master.read = hub_master_read;
|
|
hub->master.write = hub_master_write;
|
|
hub->master.send_break = hub_master_break;
|
|
hub->master.link_enable = hub_master_link_enable;
|
|
|
|
dev_set_drvdata(dev, hub);
|
|
|
|
hub_master_init(hub);
|
|
|
|
rc = fsi_master_register(&hub->master);
|
|
if (rc)
|
|
goto err_release;
|
|
|
|
/* At this point, fsi_master_register performs the device_initialize(),
|
|
* and holds the sole reference on master.dev. This means the device
|
|
* will be freed (via ->release) during any subsequent call to
|
|
* fsi_master_unregister. We add our own reference to it here, so we
|
|
* can perform cleanup (in _remove()) without it being freed before
|
|
* we're ready.
|
|
*/
|
|
get_device(&hub->master.dev);
|
|
return 0;
|
|
|
|
err_release:
|
|
fsi_slave_release_range(fsi_dev->slave, FSI_HUB_LINK_OFFSET,
|
|
FSI_HUB_LINK_SIZE * links);
|
|
return rc;
|
|
}
|
|
|
|
static int hub_master_remove(struct device *dev)
|
|
{
|
|
struct fsi_master_hub *hub = dev_get_drvdata(dev);
|
|
|
|
fsi_master_unregister(&hub->master);
|
|
fsi_slave_release_range(hub->upstream->slave, hub->addr, hub->size);
|
|
of_node_put(hub->master.dev.of_node);
|
|
|
|
/*
|
|
* master.dev will likely be ->release()ed after this, which free()s
|
|
* the hub
|
|
*/
|
|
put_device(&hub->master.dev);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct fsi_device_id hub_master_ids[] = {
|
|
{
|
|
.engine_type = FSI_ENGID_HUB_MASTER,
|
|
.version = FSI_VERSION_ANY,
|
|
},
|
|
{ 0 }
|
|
};
|
|
|
|
static struct fsi_driver hub_master_driver = {
|
|
.id_table = hub_master_ids,
|
|
.drv = {
|
|
.name = "fsi-master-hub",
|
|
.bus = &fsi_bus_type,
|
|
.probe = hub_master_probe,
|
|
.remove = hub_master_remove,
|
|
}
|
|
};
|
|
|
|
module_fsi_driver(hub_master_driver);
|
|
MODULE_LICENSE("GPL");
|