// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (C) 2006, 2007 Eugene Konev <ejka@openwrt.org>
*
* Parts of the VLYNQ specification can be found here:
* http://www.ti.com/litv/pdf/sprue36a
*/
#include <linux/init.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/device.h>
#include <linux/module.h>
#include <linux/errno.h>
#include <linux/platform_device.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/irq.h>
#include <linux/vlynq.h>
#define VLYNQ_CTRL_PM_ENABLE 0x80000000
#define VLYNQ_CTRL_CLOCK_INT 0x00008000
#define VLYNQ_CTRL_CLOCK_DIV(x) (((x) & 7) << 16)
#define VLYNQ_CTRL_INT_LOCAL 0x00004000
#define VLYNQ_CTRL_INT_ENABLE 0x00002000
#define VLYNQ_CTRL_INT_VECTOR(x) (((x) & 0x1f) << 8)
#define VLYNQ_CTRL_INT2CFG 0x00000080
#define VLYNQ_CTRL_RESET 0x00000001
#define VLYNQ_CTRL_CLOCK_MASK (0x7 << 16)
#define VLYNQ_INT_OFFSET 0x00000014
#define VLYNQ_REMOTE_OFFSET 0x00000080
#define VLYNQ_STATUS_LINK 0x00000001
#define VLYNQ_STATUS_LERROR 0x00000080
#define VLYNQ_STATUS_RERROR 0x00000100
#define VINT_ENABLE 0x00000100
#define VINT_TYPE_EDGE 0x00000080
#define VINT_LEVEL_LOW 0x00000040
#define VINT_VECTOR(x) ((x) & 0x1f)
#define VINT_OFFSET(irq) (8 * ((irq) % 4))
#define VLYNQ_AUTONEGO_V2 0x00010000
struct vlynq_regs {
u32 revision;
u32 control;
u32 status;
u32 int_prio;
u32 int_status;
u32 int_pending;
u32 int_ptr;
u32 tx_offset;
struct vlynq_mapping rx_mapping[4];
u32 chip;
u32 autonego;
u32 unused[6];
u32 int_device[8];
};
#ifdef [31mCONFIG_VLYNQ_DEBUG[0m
static void vlynq_dump_regs(struct vlynq_device *dev)
{
int i;
printk(KERN_DEBUG "VLYNQ local=%p remote=%p\n",
dev->local, dev->remote);
for (i = 0; i < 32; i++) {
printk(KERN_DEBUG "VLYNQ: local %d: %08x\n",
i + 1, ((u32 *)dev->local)[i]);
printk(KERN_DEBUG "VLYNQ: remote %d: %08x\n",
i + 1, ((u32 *)dev->remote)[i]);
}
}
static void vlynq_dump_mem(u32 *base, int count)
{
int i;
for (i = 0; i < (count + 3) / 4; i++) {
if (i % 4 == 0)
printk(KERN_DEBUG "\nMEM[0x%04x]:", i * 4);
printk(KERN_DEBUG " 0x%08x", *(base + i));
}
printk(KERN_DEBUG "\n");
}
#endif
/* Check the VLYNQ link status with a given device */
static int vlynq_linked(struct vlynq_device *dev)
{
int i;
for (i = 0; i < 100; i++)
if (readl(&dev->local->status) & VLYNQ_STATUS_LINK)
return 1;
else
cpu_relax();
return 0;
}
static void vlynq_reset(struct vlynq_device *dev)
{
writel(readl(&dev->local->control) | VLYNQ_CTRL_RESET,
&dev->local->control);
/* Wait for the devices to finish resetting */
msleep(5);
/* Remove reset bit */
writel(readl(&dev->local->control) & ~VLYNQ_CTRL_RESET,
&dev->local->control);
/* Give some time for the devices to settle */
msleep(5);
}
static void vlynq_irq_unmask(struct irq_data *d)
{
struct vlynq_device *dev = irq_data_get_irq_chip_data(d);
int virq;
u32 val;
BUG_ON(!dev);
virq = d->irq - dev->irq_start;
val = readl(&dev->remote->int_device[virq >> 2]);
val |= (VINT_ENABLE | virq) << VINT_OFFSET(virq);
writel(val, &dev->remote->int_device[virq >> 2]);
}
static void vlynq_irq_mask(struct irq_data *d)
{
struct vlynq_device *dev = irq_data_get_irq_chip_data(d);
int virq;
u32 val;
BUG_ON(!dev);
virq = d->irq - dev->irq_start;
val = readl(&dev->remote->int_device[virq >> 2]);
val &= ~(VINT_ENABLE << VINT_OFFSET(virq));
writel(val, &dev->remote->int_device[virq >> 2]);
}
static int vlynq_irq_type(struct irq_data *d, unsigned int flow_type)
{
struct vlynq_device *dev = irq_data_get_irq_chip_data(d);
int virq;
u32 val;
BUG_ON(!dev);
virq = d->irq - dev->irq_start;
val = readl(&dev->remote->int_device[virq >> 2]);
switch (flow_type & IRQ_TYPE_SENSE_MASK) {
case IRQ_TYPE_EDGE_RISING:
case IRQ_TYPE_EDGE_FALLING:
case IRQ_TYPE_EDGE_BOTH:
val |= VINT_TYPE_EDGE << VINT_OFFSET(virq);
val &= ~(VINT_LEVEL_LOW << VINT_OFFSET(virq));
break;
case IRQ_TYPE_LEVEL_HIGH:
val &= ~(VINT_TYPE_EDGE << VINT_OFFSET(virq));
val &= ~(VINT_LEVEL_LOW << VINT_OFFSET(virq));
break;
case IRQ_TYPE_LEVEL_LOW:
val &= ~(VINT_TYPE_EDGE << VINT_OFFSET(virq));
val |= VINT_LEVEL_LOW << VINT_OFFSET(virq);
break;
default:
return -EINVAL;
}
writel(val, &dev->remote->int_device[virq >> 2]);
return 0;
}
static void vlynq_local_ack(struct irq_data *d)
{
struct vlynq_device *dev = irq_data_get_irq_chip_data(d);
u32 status = readl(&dev->local->status);
pr_debug("%s: local status: 0x%08x\n",
dev_name(&dev->dev), status);
writel(status, &dev->local->status);
}
static void vlynq_remote_ack(struct irq_data *d)
{
struct vlynq_device *dev = irq_data_get_irq_chip_data(d);
u32 status = readl(&dev->remote->status);
pr_debug("%s: remote status: 0x%08x\n",
dev_name(&dev->dev), status);
writel(status, &dev->remote->status);
}
static irqreturn_t vlynq_irq(int irq, void *dev_id)
{
struct vlynq_device *dev = dev_id;
u32 status;
int virq = 0;
status = readl(&dev->local->int_status);
writel(status, &dev->local->int_status);
if (unlikely(!status))
spurious_interrupt();
while (status) {
if (status & 1)
do_IRQ(dev->irq_start + virq);
status >>= 1;
virq++;
}
return IRQ_HANDLED;
}
static struct irq_chip vlynq_irq_chip = {
.name = "vlynq",
.irq_unmask = vlynq_irq_unmask,
.irq_mask = vlynq_irq_mask,
.irq_set_type = vlynq_irq_type,
};
static struct irq_chip vlynq_local_chip = {
.name = "vlynq local error",
.irq_unmask = vlynq_irq_unmask,
.irq_mask = vlynq_irq_mask,
.irq_ack = vlynq_local_ack,
};
static struct irq_chip vlynq_remote_chip = {
.name = "vlynq local error",
.irq_unmask = vlynq_irq_unmask,
.irq_mask = vlynq_irq_mask,
.irq_ack = vlynq_remote_ack,
};
static int vlynq_setup_irq(struct vlynq_device *dev)
{
u32 val;
int i, virq;
if (dev->local_irq == dev->remote_irq) {
printk(KERN_ERR
"%s: local vlynq irq should be different from remote\n",
dev_name(&dev->dev));
return -EINVAL;
}
/* Clear local and remote error bits */
writel(readl(&dev->local->status), &dev->local->status);
writel(readl(&dev->remote->status), &dev->remote->status);
/* Now setup interrupts */
val = VLYNQ_CTRL_INT_VECTOR(dev->local_irq);
val |= VLYNQ_CTRL_INT_ENABLE | VLYNQ_CTRL_INT_LOCAL |
VLYNQ_CTRL_INT2CFG;
val |= readl(&dev->local->control);
writel(VLYNQ_INT_OFFSET, &dev->local->int_ptr);
writel(val, &dev->local->control);
val = VLYNQ_CTRL_INT_VECTOR(dev->remote_irq);
val |= VLYNQ_CTRL_INT_ENABLE;
val |= readl(&dev->remote->control);
writel(VLYNQ_INT_OFFSET, &dev->remote->int_ptr);
writel(val, &dev->remote->int_ptr);
writel(val, &dev->remote->control);
for (i = dev->irq_start; i <= dev->irq_end; i++) {
virq = i - dev->irq_start;
if (virq == dev->local_irq) {
irq_set_chip_and_handler(i, &vlynq_local_chip,
handle_level_irq);
irq_set_chip_data(i, dev);
} else if (virq == dev->remote_irq) {
irq_set_chip_and_handler(i, &vlynq_remote_chip,
handle_level_irq);
irq_set_chip_data(i, dev);
} else {
irq_set_chip_and_handler(i, &vlynq_irq_chip,
handle_simple_irq);
irq_set_chip_data(i, dev);
writel(0, &dev->remote->int_device[virq >> 2]);
}
}
if (request_irq(dev->irq, vlynq_irq, IRQF_SHARED, "vlynq", dev)) {
printk(KERN_ERR "%s: request_irq failed\n",
dev_name(&dev->dev));
return -EAGAIN;
}
return 0;
}
static void vlynq_device_release(struct device *dev)
{
struct vlynq_device *vdev = to_vlynq_device(dev);
kfree(vdev);
}
static int vlynq_device_match(struct device *dev,
struct device_driver *drv)
{
struct vlynq_device *vdev = to_vlynq_device(dev);
struct vlynq_driver *vdrv = to_vlynq_driver(drv);
struct vlynq_device_id *ids = vdrv->id_table;
while (ids->id) {
if (ids->id == vdev->dev_id) {
vdev->divisor = ids->divisor;
vlynq_set_drvdata(vdev, ids);
printk(KERN_INFO "Driver found for VLYNQ "
"device: %08x\n", vdev->dev_id);
return 1;
}
printk(KERN_DEBUG "Not using the %08x VLYNQ device's driver"
" for VLYNQ device: %08x\n", ids->id, vdev->dev_id);
ids++;
}
return 0;
}
static int vlynq_device_probe(struct device *dev)
{
struct vlynq_device *vdev = to_vlynq_device(dev);
struct vlynq_driver *drv = to_vlynq_driver(dev->driver);
struct vlynq_device_id *id = vlynq_get_drvdata(vdev);
int result = -ENODEV;
if (drv->probe)
result = drv->probe(vdev, id);
if (result)
put_device(dev);
return result;
}
static int vlynq_device_remove(struct device *dev)
{
struct vlynq_driver *drv = to_vlynq_driver(dev->driver);
if (drv->remove)
drv->remove(to_vlynq_device(dev));
return 0;
}
int __vlynq_register_driver(struct vlynq_driver *driver, struct module *owner)
{
driver->driver.name = driver->name;
driver->driver.bus = &vlynq_bus_type;
return driver_register(&driver->driver);
}
EXPORT_SYMBOL(__vlynq_register_driver);
void vlynq_unregister_driver(struct vlynq_driver *driver)
{
driver_unregister(&driver->driver);
}
EXPORT_SYMBOL(vlynq_unregister_driver);
/*
* A VLYNQ remote device can clock the VLYNQ bus master
* using a dedicated clock line. In that case, both the
* remove device and the bus master should have the same
* serial clock dividers configured. Iterate through the
* 8 possible dividers until we actually link with the
* device.
*/
static int __vlynq_try_remote(struct vlynq_device *dev)
{
int i;
vlynq_reset(dev);
for (i = dev->dev_id ? vlynq_rdiv2 : vlynq_rdiv8; dev->dev_id ?
i <= vlynq_rdiv8 : i >= vlynq_rdiv2;
dev->dev_id ? i++ : i--) {
if (!vlynq_linked(dev))
break;
writel((readl(&dev->remote->control) &
~VLYNQ_CTRL_CLOCK_MASK) |
VLYNQ_CTRL_CLOCK_INT |
VLYNQ_CTRL_CLOCK_DIV(i - vlynq_rdiv1),
&dev->remote->control);
writel((readl(&dev->local->control)
& ~(VLYNQ_CTRL_CLOCK_INT |
VLYNQ_CTRL_CLOCK_MASK)) |
VLYNQ_CTRL_CLOCK_DIV(i - vlynq_rdiv1),
&dev->local->control);
if (vlynq_linked(dev)) {
printk(KERN_DEBUG
"%s: using remote clock divisor %d\n",
dev_name(&dev->dev), i - vlynq_rdiv1 + 1);
dev->divisor = i;
return 0;
} else {
vlynq_reset(dev);
}
}
return -ENODEV;
}
/*
* A VLYNQ remote device can be clocked by the VLYNQ bus
* master using a dedicated clock line. In that case, only
* the bus master configures the serial clock divider.
* Iterate through the 8 possible dividers until we
* actually get a link with the device.
*/
static int __vlynq_try_local(struct vlynq_device *dev)
{
int i;
vlynq_reset(dev);
for (i = dev->dev_id ? vlynq_ldiv2 : vlynq_ldiv8; dev->dev_id ?
i <= vlynq_ldiv8 : i >= vlynq_ldiv2;
dev->dev_id ? i++ : i--) {
writel((readl(&dev->local->control) &
~VLYNQ_CTRL_CLOCK_MASK) |
VLYNQ_CTRL_CLOCK_INT |
VLYNQ_CTRL_CLOCK_DIV(i - vlynq_ldiv1),
&dev->local->control);
if (vlynq_linked(dev)) {
printk(KERN_DEBUG
"%s: using local clock divisor %d\n",
dev_name(&dev->dev), i - vlynq_ldiv1 + 1);
dev->divisor = i;
return 0;
} else {
vlynq_reset(dev);
}
}
return -ENODEV;
}
/*
* When using external clocking method, serial clock
* is supplied by an external oscillator, therefore we
* should mask the local clock bit in the clock control
* register for both the bus master and the remote device.
*/
static int __vlynq_try_external(struct vlynq_device *dev)
{
vlynq_reset(dev);
if (!vlynq_linked(dev))
return -ENODEV;
writel((readl(&dev->remote->control) &
~VLYNQ_CTRL_CLOCK_INT),
&dev->remote->control);
writel((readl(&dev->local->control) &
~VLYNQ_CTRL_CLOCK_INT),
&dev->local->control);
if (vlynq_linked(dev)) {
printk(KERN_DEBUG "%s: using external clock\n",
dev_name(&dev->dev));
dev->divisor = vlynq_div_external;
return 0;
}
return -ENODEV;
}
static int __vlynq_enable_device(struct vlynq_device *dev)
{
int result;
struct plat_vlynq_ops *ops = dev->dev.platform_data;
result = ops->on(dev);
if (result)
return result;
switch (dev->divisor) {
case vlynq_div_external:
case vlynq_div_auto:
/* When the device is brought from reset it should have clock
* generation negotiated by hardware.
* Check which device is generating clocks and perform setup
* accordingly */
if (vlynq_linked(dev) && readl(&dev->remote->control) &
VLYNQ_CTRL_CLOCK_INT) {
if (!__vlynq_try_remote(dev) ||
!__vlynq_try_local(dev) ||
!__vlynq_try_external(dev))
return 0;
} else {
if (!__vlynq_try_external(dev) ||
!__vlynq_try_local(dev) ||
!__vlynq_try_remote(dev))
return 0;
}
break;
case vlynq_ldiv1:
case vlynq_ldiv2:
case vlynq_ldiv3:
case vlynq_ldiv4:
case vlynq_ldiv5:
case vlynq_ldiv6:
case vlynq_ldiv7:
case vlynq_ldiv8:
writel(VLYNQ_CTRL_CLOCK_INT |
VLYNQ_CTRL_CLOCK_DIV(dev->divisor -
vlynq_ldiv1), &dev->local->control);
writel(0, &dev->remote->control);
if (vlynq_linked(dev)) {
printk(KERN_DEBUG
"%s: using local clock divisor %d\n",
dev_name(&dev->dev),
dev->divisor - vlynq_ldiv1 + 1);
return 0;
}
break;
case vlynq_rdiv1:
case vlynq_rdiv2:
case vlynq_rdiv3:
case vlynq_rdiv4:
case vlynq_rdiv5:
case vlynq_rdiv6:
case vlynq_rdiv7:
case vlynq_rdiv8:
writel(0, &dev->local->control);
writel(VLYNQ_CTRL_CLOCK_INT |
VLYNQ_CTRL_CLOCK_DIV(dev->divisor -
vlynq_rdiv1), &dev->remote->control);
if (vlynq_linked(dev)) {
printk(KERN_DEBUG
"%s: using remote clock divisor %d\n",
dev_name(&dev->dev),
dev->divisor - vlynq_rdiv1 + 1);
return 0;
}
break;
}
ops->off(dev);
return -ENODEV;
}
int vlynq_enable_device(struct vlynq_device *dev)
{
struct plat_vlynq_ops *ops = dev->dev.platform_data;
int result = -ENODEV;
result = __vlynq_enable_device(dev);
if (result)
return result;
result = vlynq_setup_irq(dev);
if (result)
ops->off(dev);
dev->enabled = !result;
return result;
}
EXPORT_SYMBOL(vlynq_enable_device);
void vlynq_disable_device(struct vlynq_device *dev)
{
struct plat_vlynq_ops *ops = dev->dev.platform_data;
dev->enabled = 0;
free_irq(dev->irq, dev);
ops->off(dev);
}
EXPORT_SYMBOL(vlynq_disable_device);
int vlynq_set_local_mapping(struct vlynq_device *dev, u32 tx_offset,
struct vlynq_mapping *mapping)
{
int i;
if (!dev->enabled)
return -ENXIO;
writel(tx_offset, &dev->local->tx_offset);
for (i = 0; i < 4; i++) {
writel(mapping[i].offset, &dev->local->rx_mapping[i].offset);
writel(mapping[i].size, &dev->local->rx_mapping[i].size);
}
return 0;
}
EXPORT_SYMBOL(vlynq_set_local_mapping);
int vlynq_set_remote_mapping(struct vlynq_device *dev, u32 tx_offset,
struct vlynq_mapping *mapping)
{
int i;
if (!dev->enabled)
return -ENXIO;
writel(tx_offset, &dev->remote->tx_offset);
for (i = 0; i < 4; i++) {
writel(mapping[i].offset, &dev->remote->rx_mapping[i].offset);
writel(mapping[i].size, &dev->remote->rx_mapping[i].size);
}
return 0;
}
EXPORT_SYMBOL(vlynq_set_remote_mapping);
int vlynq_set_local_irq(struct vlynq_device *dev, int virq)
{
int irq = dev->irq_start + virq;
if (dev->enabled)
return -EBUSY;
if ((irq < dev->irq_start) || (irq > dev->irq_end))
return -EINVAL;
if (virq == dev->remote_irq)
return -EINVAL;
dev->local_irq = virq;
return 0;
}
EXPORT_SYMBOL(vlynq_set_local_irq);
int vlynq_set_remote_irq(struct vlynq_device *dev, int virq)
{
int irq = dev->irq_start + virq;
if (dev->enabled)
return -EBUSY;
if ((irq < dev->irq_start) || (irq > dev->irq_end))
return -EINVAL;
if (virq == dev->local_irq)
return -EINVAL;
dev->remote_irq = virq;
return 0;
}
EXPORT_SYMBOL(vlynq_set_remote_irq);
static int vlynq_probe(struct platform_device *pdev)
{
struct vlynq_device *dev;
struct resource *regs_res, *mem_res, *irq_res;
int len, result;
regs_res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "regs");
if (!regs_res)
return -ENODEV;
mem_res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "mem");
if (!mem_res)
return -ENODEV;
irq_res = platform_get_resource_byname(pdev, IORESOURCE_IRQ, "devirq");
if (!irq_res)
return -ENODEV;
dev = kzalloc(sizeof(*dev), GFP_KERNEL);
if (!dev) {
printk(KERN_ERR
"vlynq: failed to allocate device structure\n");
return -ENOMEM;
}
dev->id = pdev->id;
dev->dev.bus = &vlynq_bus_type;
dev->dev.parent = &pdev->dev;
dev_set_name(&dev->dev, "vlynq%d", dev->id);
dev->dev.platform_data = pdev->dev.platform_data;
dev->dev.release = vlynq_device_release;
dev->regs_start = regs_res->start;
dev->regs_end = regs_res->end;
dev->mem_start = mem_res->start;
dev->mem_end = mem_res->end;
len = resource_size(regs_res);
if (!request_mem_region(regs_res->start, len, dev_name(&dev->dev))) {
printk(KERN_ERR "%s: Can't request vlynq registers\n",
dev_name(&dev->dev));
result = -ENXIO;
goto fail_request;
}
dev->local = ioremap(regs_res->start, len);
if (!dev->local) {
printk(KERN_ERR "%s: Can't remap vlynq registers\n",
dev_name(&dev->dev));
result = -ENXIO;
goto fail_remap;
}
dev->remote = (struct vlynq_regs *)((void *)dev->local +
VLYNQ_REMOTE_OFFSET);
dev->irq = platform_get_irq_byname(pdev, "irq");
dev->irq_start = irq_res->start;
dev->irq_end = irq_res->end;
dev->local_irq = dev->irq_end - dev->irq_start;
dev->remote_irq = dev->local_irq - 1;
if (device_register(&dev->dev))
goto fail_register;
platform_set_drvdata(pdev, dev);
printk(KERN_INFO "%s: regs 0x%p, irq %d, mem 0x%p\n",
dev_name(&dev->dev), (void *)dev->regs_start, dev->irq,
(void *)dev->mem_start);
dev->dev_id = 0;
dev->divisor = vlynq_div_auto;
result = __vlynq_enable_device(dev);
if (result == 0) {
dev->dev_id = readl(&dev->remote->chip);
((struct plat_vlynq_ops *)(dev->dev.platform_data))->off(dev);
}
if (dev->dev_id)
printk(KERN_INFO "Found a VLYNQ device: %08x\n", dev->dev_id);
return 0;
fail_register:
iounmap(dev->local);
fail_remap:
fail_request:
release_mem_region(regs_res->start, len);
kfree(dev);
return result;
}
static int vlynq_remove(struct platform_device *pdev)
{
struct vlynq_device *dev = platform_get_drvdata(pdev);
device_unregister(&dev->dev);
iounmap(dev->local);
release_mem_region(dev->regs_start,
dev->regs_end - dev->regs_start + 1);
kfree(dev);
return 0;
}
static struct platform_driver vlynq_platform_driver = {
.driver.name = "vlynq",
.probe = vlynq_probe,
.remove = vlynq_remove,
};
struct bus_type vlynq_bus_type = {
.name = "vlynq",
.match = vlynq_device_match,
.probe = vlynq_device_probe,
.remove = vlynq_device_remove,
};
EXPORT_SYMBOL(vlynq_bus_type);
static int vlynq_init(void)
{
int res = 0;
res = bus_register(&vlynq_bus_type);
if (res)
goto fail_bus;
res = platform_driver_register(&vlynq_platform_driver);
if (res)
goto fail_platform;
return 0;
fail_platform:
bus_unregister(&vlynq_bus_type);
fail_bus:
return res;
}
static void vlynq_exit(void)
{
platform_driver_unregister(&vlynq_platform_driver);
bus_unregister(&vlynq_bus_type);
}
module_init(vlynq_init);
module_exit(vlynq_exit);