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path: root/drivers/serial/8250.c
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Diffstat (limited to 'drivers/serial/8250.c')
-rw-r--r--drivers/serial/8250.c92
1 files changed, 71 insertions, 21 deletions
diff --git a/drivers/serial/8250.c b/drivers/serial/8250.c
index d3ca7d32abe0..303272af386e 100644
--- a/drivers/serial/8250.c
+++ b/drivers/serial/8250.c
@@ -156,11 +156,15 @@ struct uart_8250_port {
};
struct irq_info {
- spinlock_t lock;
+ struct hlist_node node;
+ int irq;
+ spinlock_t lock; /* Protects list not the hash */
struct list_head *head;
};
-static struct irq_info irq_lists[NR_IRQS];
+#define NR_IRQ_HASH 32 /* Can be adjusted later */
+static struct hlist_head irq_lists[NR_IRQ_HASH];
+static DEFINE_MUTEX(hash_mutex); /* Used to walk the hash */
/*
* Here we define the default xmit fifo size used for each type of UART.
@@ -1545,15 +1549,43 @@ static void serial_do_unlink(struct irq_info *i, struct uart_8250_port *up)
BUG_ON(i->head != &up->list);
i->head = NULL;
}
-
spin_unlock_irq(&i->lock);
+ /* List empty so throw away the hash node */
+ if (i->head == NULL) {
+ hlist_del(&i->node);
+ kfree(i);
+ }
}
static int serial_link_irq_chain(struct uart_8250_port *up)
{
- struct irq_info *i = irq_lists + up->port.irq;
+ struct hlist_head *h;
+ struct hlist_node *n;
+ struct irq_info *i;
int ret, irq_flags = up->port.flags & UPF_SHARE_IRQ ? IRQF_SHARED : 0;
+ mutex_lock(&hash_mutex);
+
+ h = &irq_lists[up->port.irq % NR_IRQ_HASH];
+
+ hlist_for_each(n, h) {
+ i = hlist_entry(n, struct irq_info, node);
+ if (i->irq == up->port.irq)
+ break;
+ }
+
+ if (n == NULL) {
+ i = kzalloc(sizeof(struct irq_info), GFP_KERNEL);
+ if (i == NULL) {
+ mutex_unlock(&hash_mutex);
+ return -ENOMEM;
+ }
+ spin_lock_init(&i->lock);
+ i->irq = up->port.irq;
+ hlist_add_head(&i->node, h);
+ }
+ mutex_unlock(&hash_mutex);
+
spin_lock_irq(&i->lock);
if (i->head) {
@@ -1577,14 +1609,28 @@ static int serial_link_irq_chain(struct uart_8250_port *up)
static void serial_unlink_irq_chain(struct uart_8250_port *up)
{
- struct irq_info *i = irq_lists + up->port.irq;
+ struct irq_info *i;
+ struct hlist_node *n;
+ struct hlist_head *h;
+ mutex_lock(&hash_mutex);
+
+ h = &irq_lists[up->port.irq % NR_IRQ_HASH];
+
+ hlist_for_each(n, h) {
+ i = hlist_entry(n, struct irq_info, node);
+ if (i->irq == up->port.irq)
+ break;
+ }
+
+ BUG_ON(n == NULL);
BUG_ON(i->head == NULL);
if (list_empty(i->head))
free_irq(up->port.irq, i);
serial_do_unlink(i, up);
+ mutex_unlock(&hash_mutex);
}
/* Base timer interval for polling */
@@ -2223,9 +2269,9 @@ serial8250_set_termios(struct uart_port *port, struct ktermios *termios,
serial_outp(up, UART_EFR, efr);
}
-#ifdef CONFIG_ARCH_OMAP15XX
+#ifdef CONFIG_ARCH_OMAP
/* Workaround to enable 115200 baud on OMAP1510 internal ports */
- if (cpu_is_omap1510() && is_omap_port((unsigned int)up->port.membase)) {
+ if (cpu_is_omap1510() && is_omap_port(up)) {
if (baud == 115200) {
quot = 1;
serial_out(up, UART_OMAP_OSC_12M_SEL, 1);
@@ -2278,18 +2324,27 @@ serial8250_pm(struct uart_port *port, unsigned int state,
p->pm(port, state, oldstate);
}
+static unsigned int serial8250_port_size(struct uart_8250_port *pt)
+{
+ if (pt->port.iotype == UPIO_AU)
+ return 0x100000;
+#ifdef CONFIG_ARCH_OMAP
+ if (is_omap_port(pt))
+ return 0x16 << pt->port.regshift;
+#endif
+ return 8 << pt->port.regshift;
+}
+
/*
* Resource handling.
*/
static int serial8250_request_std_resource(struct uart_8250_port *up)
{
- unsigned int size = 8 << up->port.regshift;
+ unsigned int size = serial8250_port_size(up);
int ret = 0;
switch (up->port.iotype) {
case UPIO_AU:
- size = 0x100000;
- /* fall thru */
case UPIO_TSI:
case UPIO_MEM32:
case UPIO_MEM:
@@ -2323,12 +2378,10 @@ static int serial8250_request_std_resource(struct uart_8250_port *up)
static void serial8250_release_std_resource(struct uart_8250_port *up)
{
- unsigned int size = 8 << up->port.regshift;
+ unsigned int size = serial8250_port_size(up);
switch (up->port.iotype) {
case UPIO_AU:
- size = 0x100000;
- /* fall thru */
case UPIO_TSI:
case UPIO_MEM32:
case UPIO_MEM:
@@ -2440,7 +2493,7 @@ static void serial8250_config_port(struct uart_port *port, int flags)
static int
serial8250_verify_port(struct uart_port *port, struct serial_struct *ser)
{
- if (ser->irq >= NR_IRQS || ser->irq < 0 ||
+ if (ser->irq >= nr_irqs || ser->irq < 0 ||
ser->baud_base < 9600 || ser->type < PORT_UNKNOWN ||
ser->type >= ARRAY_SIZE(uart_config) || ser->type == PORT_CIRRUS ||
ser->type == PORT_STARTECH)
@@ -2960,7 +3013,7 @@ EXPORT_SYMBOL(serial8250_unregister_port);
static int __init serial8250_init(void)
{
- int ret, i;
+ int ret;
if (nr_uarts > UART_NR)
nr_uarts = UART_NR;
@@ -2969,9 +3022,6 @@ static int __init serial8250_init(void)
"%d ports, IRQ sharing %sabled\n", nr_uarts,
share_irqs ? "en" : "dis");
- for (i = 0; i < NR_IRQS; i++)
- spin_lock_init(&irq_lists[i].lock);
-
#ifdef CONFIG_SPARC
ret = sunserial_register_minors(&serial8250_reg, UART_NR);
#else
@@ -2999,15 +3049,15 @@ static int __init serial8250_init(void)
goto out;
platform_device_del(serial8250_isa_devs);
- put_dev:
+put_dev:
platform_device_put(serial8250_isa_devs);
- unreg_uart_drv:
+unreg_uart_drv:
#ifdef CONFIG_SPARC
sunserial_unregister_minors(&serial8250_reg, UART_NR);
#else
uart_unregister_driver(&serial8250_reg);
#endif
- out:
+out:
return ret;
}