u-boot/drivers/serial/altera_uart.c
Tom Rini 83d290c56f SPDX: Convert all of our single license tags to Linux Kernel style
When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from.  So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry.  Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.

In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.

This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents.  There's also a few places where I found we did not have a tag
and have introduced one.

Signed-off-by: Tom Rini <trini@konsulko.com>
2018-05-07 09:34:12 -04:00

152 lines
3.3 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* (C) Copyright 2004, Psyent Corporation <www.psyent.com>
* Scott McNutt <smcnutt@psyent.com>
*/
#include <common.h>
#include <dm.h>
#include <errno.h>
#include <serial.h>
#include <asm/io.h>
DECLARE_GLOBAL_DATA_PTR;
/* status register */
#define ALTERA_UART_TMT BIT(5) /* tx empty */
#define ALTERA_UART_TRDY BIT(6) /* tx ready */
#define ALTERA_UART_RRDY BIT(7) /* rx ready */
struct altera_uart_regs {
u32 rxdata; /* Rx data reg */
u32 txdata; /* Tx data reg */
u32 status; /* Status reg */
u32 control; /* Control reg */
u32 divisor; /* Baud rate divisor reg */
u32 endofpacket; /* End-of-packet reg */
};
struct altera_uart_platdata {
struct altera_uart_regs *regs;
unsigned int uartclk;
};
static int altera_uart_setbrg(struct udevice *dev, int baudrate)
{
struct altera_uart_platdata *plat = dev->platdata;
struct altera_uart_regs *const regs = plat->regs;
u32 div;
div = (plat->uartclk / baudrate) - 1;
writel(div, &regs->divisor);
return 0;
}
static int altera_uart_putc(struct udevice *dev, const char ch)
{
struct altera_uart_platdata *plat = dev->platdata;
struct altera_uart_regs *const regs = plat->regs;
if (!(readl(&regs->status) & ALTERA_UART_TRDY))
return -EAGAIN;
writel(ch, &regs->txdata);
return 0;
}
static int altera_uart_pending(struct udevice *dev, bool input)
{
struct altera_uart_platdata *plat = dev->platdata;
struct altera_uart_regs *const regs = plat->regs;
u32 st = readl(&regs->status);
if (input)
return st & ALTERA_UART_RRDY ? 1 : 0;
else
return !(st & ALTERA_UART_TMT);
}
static int altera_uart_getc(struct udevice *dev)
{
struct altera_uart_platdata *plat = dev->platdata;
struct altera_uart_regs *const regs = plat->regs;
if (!(readl(&regs->status) & ALTERA_UART_RRDY))
return -EAGAIN;
return readl(&regs->rxdata) & 0xff;
}
static int altera_uart_probe(struct udevice *dev)
{
return 0;
}
static int altera_uart_ofdata_to_platdata(struct udevice *dev)
{
struct altera_uart_platdata *plat = dev_get_platdata(dev);
plat->regs = map_physmem(devfdt_get_addr(dev),
sizeof(struct altera_uart_regs),
MAP_NOCACHE);
plat->uartclk = fdtdec_get_int(gd->fdt_blob, dev_of_offset(dev),
"clock-frequency", 0);
return 0;
}
static const struct dm_serial_ops altera_uart_ops = {
.putc = altera_uart_putc,
.pending = altera_uart_pending,
.getc = altera_uart_getc,
.setbrg = altera_uart_setbrg,
};
static const struct udevice_id altera_uart_ids[] = {
{ .compatible = "altr,uart-1.0" },
{}
};
U_BOOT_DRIVER(altera_uart) = {
.name = "altera_uart",
.id = UCLASS_SERIAL,
.of_match = altera_uart_ids,
.ofdata_to_platdata = altera_uart_ofdata_to_platdata,
.platdata_auto_alloc_size = sizeof(struct altera_uart_platdata),
.probe = altera_uart_probe,
.ops = &altera_uart_ops,
.flags = DM_FLAG_PRE_RELOC,
};
#ifdef CONFIG_DEBUG_UART_ALTERA_UART
#include <debug_uart.h>
static inline void _debug_uart_init(void)
{
struct altera_uart_regs *regs = (void *)CONFIG_DEBUG_UART_BASE;
u32 div;
div = (CONFIG_DEBUG_UART_CLOCK / CONFIG_BAUDRATE) - 1;
writel(div, &regs->divisor);
}
static inline void _debug_uart_putc(int ch)
{
struct altera_uart_regs *regs = (void *)CONFIG_DEBUG_UART_BASE;
while (1) {
u32 st = readl(&regs->status);
if (st & ALTERA_UART_TRDY)
break;
}
writel(ch, &regs->txdata);
}
DEBUG_UART_FUNCS
#endif