u-boot/drivers/serial/serial_intel_mid.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

68 lines
1.6 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (c) 2017 Intel Corporation
*/
#include <common.h>
#include <dm.h>
#include <ns16550.h>
#include <serial.h>
/*
* The UART clock is calculated as
*
* UART clock = XTAL * UART_MUL / UART_DIV
*
* The baudrate is calculated as
*
* baud rate = UART clock / UART_PS / DLAB
*/
#define UART_PS 0x30
#define UART_MUL 0x34
#define UART_DIV 0x38
static void mid_writel(struct ns16550_platdata *plat, int offset, int value)
{
unsigned char *addr;
offset *= 1 << plat->reg_shift;
addr = (unsigned char *)plat->base + offset;
writel(value, addr + plat->reg_offset);
}
static int mid_serial_probe(struct udevice *dev)
{
struct ns16550_platdata *plat = dev_get_platdata(dev);
/*
* Initialize fractional divider correctly for Intel Edison
* platform.
*
* For backward compatibility we have to set initial DLAB value
* to 16 and speed to 115200 baud, where initial frequency is
* 29491200Hz, and XTAL frequency is 38.4MHz.
*/
mid_writel(plat, UART_MUL, 96);
mid_writel(plat, UART_DIV, 125);
mid_writel(plat, UART_PS, 16);
return ns16550_serial_probe(dev);
}
static const struct udevice_id mid_serial_ids[] = {
{ .compatible = "intel,mid-uart" },
{}
};
U_BOOT_DRIVER(serial_intel_mid) = {
.name = "serial_intel_mid",
.id = UCLASS_SERIAL,
.of_match = mid_serial_ids,
.ofdata_to_platdata = ns16550_serial_ofdata_to_platdata,
.platdata_auto_alloc_size = sizeof(struct ns16550_platdata),
.priv_auto_alloc_size = sizeof(struct NS16550),
.probe = mid_serial_probe,
.ops = &ns16550_serial_ops,
.flags = DM_FLAG_PRE_RELOC,
};