[ARM] S3C64XX: Demux UART interrupts

Add demux handling for the UART interrupts
generated by the VIC into their seperate IRQs
that the serial driver can register.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
This commit is contained in:
Ben Dooks 2008-10-21 14:07:05 +01:00
parent b73c289cc9
commit 3e694d4bc6
2 changed files with 147 additions and 1 deletions

View file

@ -24,6 +24,14 @@
#define S3C_PA_UART3 (S3C_PA_UART + 0xC00)
#define S3C_UART_OFFSET (0x400)
/* See notes on UART VA mapping in debug-macro.S */
#define S3C_VA_UARTx(x) (S3C_VA_UART + (S3C_PA_UART & 0xfffff) + ((x) * S3C_UART_OFFSET))
#define S3C_VA_UART0 S3C_VA_UARTx(0)
#define S3C_VA_UART1 S3C_VA_UARTx(1)
#define S3C_VA_UART2 S3C_VA_UARTx(2)
#define S3C_VA_UART3 S3C_VA_UARTx(3)
#define S3C64XX_PA_SYSCON (0x7E00F000)
#define S3C64XX_PA_TIMER (0x7F006000)

View file

@ -91,9 +91,144 @@ static struct irq_chip s3c_irq_timer = {
.ack = s3c_irq_timer_ack,
};
struct uart_irq {
void __iomem *regs;
unsigned int base_irq;
unsigned int parent_irq;
};
/* Note, we make use of the fact that the parent IRQs, IRQ_UART[0..3]
* are consecutive when looking up the interrupt in the demux routines.
*/
static struct uart_irq uart_irqs[] = {
[0] = {
.regs = S3C_VA_UART0,
.base_irq = IRQ_S3CUART_BASE0,
.parent_irq = IRQ_UART0,
},
[1] = {
.regs = S3C_VA_UART1,
.base_irq = IRQ_S3CUART_BASE1,
.parent_irq = IRQ_UART1,
},
[2] = {
.regs = S3C_VA_UART2,
.base_irq = IRQ_S3CUART_BASE2,
.parent_irq = IRQ_UART2,
},
[3] = {
.regs = S3C_VA_UART3,
.base_irq = IRQ_S3CUART_BASE3,
.parent_irq = IRQ_UART3,
},
};
static inline void __iomem *s3c_irq_uart_base(unsigned int irq)
{
struct uart_irq *uirq = get_irq_chip_data(irq);
return uirq->regs;
}
static inline unsigned int s3c_irq_uart_bit(unsigned int irq)
{
return irq & 3;
}
/* UART interrupt registers, not worth adding to seperate include header */
#define S3C64XX_UINTP 0x30
#define S3C64XX_UINTSP 0x34
#define S3C64XX_UINTM 0x38
static void s3c_irq_uart_mask(unsigned int irq)
{
void __iomem *regs = s3c_irq_uart_base(irq);
unsigned int bit = s3c_irq_uart_bit(irq);
u32 reg;
reg = __raw_readl(regs + S3C64XX_UINTM);
reg |= (1 << bit);
__raw_writel(reg, regs + S3C64XX_UINTM);
}
static void s3c_irq_uart_maskack(unsigned int irq)
{
void __iomem *regs = s3c_irq_uart_base(irq);
unsigned int bit = s3c_irq_uart_bit(irq);
u32 reg;
reg = __raw_readl(regs + S3C64XX_UINTM);
reg |= (1 << bit);
__raw_writel(reg, regs + S3C64XX_UINTM);
__raw_writel(1 << bit, regs + S3C64XX_UINTP);
}
static void s3c_irq_uart_unmask(unsigned int irq)
{
void __iomem *regs = s3c_irq_uart_base(irq);
unsigned int bit = s3c_irq_uart_bit(irq);
u32 reg;
reg = __raw_readl(regs + S3C64XX_UINTM);
reg &= ~(1 << bit);
__raw_writel(reg, regs + S3C64XX_UINTM);
}
static void s3c_irq_uart_ack(unsigned int irq)
{
void __iomem *regs = s3c_irq_uart_base(irq);
unsigned int bit = s3c_irq_uart_bit(irq);
__raw_writel(1 << bit, regs + S3C64XX_UINTP);
}
static void s3c_irq_demux_uart(unsigned int irq, struct irq_desc *desc)
{
struct uart_irq *uirq = &uart_irqs[irq - IRQ_UART0];
u32 pend = __raw_readl(uirq->regs + S3C64XX_UINTP);
int base = uirq->base_irq;
if (pend & (1 << 0))
generic_handle_irq(base);
if (pend & (1 << 1))
generic_handle_irq(base + 1);
if (pend & (1 << 2))
generic_handle_irq(base + 2);
if (pend & (1 << 3))
generic_handle_irq(base + 3);
}
static struct irq_chip s3c_irq_uart = {
.name = "s3c-uart",
.mask = s3c_irq_uart_mask,
.unmask = s3c_irq_uart_unmask,
.mask_ack = s3c_irq_uart_maskack,
.ack = s3c_irq_uart_ack,
};
static void __init s3c64xx_uart_irq(struct uart_irq *uirq)
{
void *reg_base = uirq->regs;
unsigned int irq;
int offs;
/* mask all interrupts at the start. */
__raw_writel(0xf, reg_base + S3C64XX_UINTM);
for (offs = 0; offs < 3; offs++) {
irq = uirq->base_irq + offs;
set_irq_chip(irq, &s3c_irq_uart);
set_irq_chip_data(irq, uirq);
set_irq_handler(irq, handle_level_irq);
set_irq_flags(irq, IRQF_VALID);
}
set_irq_chained_handler(uirq->parent_irq, s3c_irq_demux_uart);
}
void __init s3c64xx_init_irq(u32 vic0_valid, u32 vic1_valid)
{
int irq;
int uart, irq;
printk(KERN_INFO "%s: initialising interrupts\n", __func__);
@ -114,6 +249,9 @@ void __init s3c64xx_init_irq(u32 vic0_valid, u32 vic1_valid)
set_irq_handler(irq, handle_level_irq);
set_irq_flags(irq, IRQF_VALID);
}
for (uart = 0; uart < ARRAY_SIZE(uart_irqs); uart++)
s3c64xx_uart_irq(&uart_irqs[uart]);
}