uboot-phytec

// SPDX-License-Identifier: GPL-2.0+

/*

 * (C) Copyright 2016 Stephen Warren <swarren@wwwdotorg.org>

 *

 * Derived from pl01x code:

 *

 * (C) Copyright 2000

 * Rob Taylor, Flying Pig Systems. robt@flyingpig.com.

 *

 * (C) Copyright 2004

 * ARM Ltd.

 * Philippe Robin, <philippe.robin@arm.com>

 */

​

/* Simple U-Boot driver for the BCM283x mini UART */

​

#include <common.h>

#include <dm.h>

#include <errno.h>

#include <watchdog.h>

#include <asm/gpio.h>

#include <asm/io.h>

#include <serial.h>

#include <dm/platform_data/serial_bcm283x_mu.h>

#include <dm/pinctrl.h>

#include <linux/compiler.h>

​

struct bcm283x_mu_regs {

    u32 io;

    u32 iir;

    u32 ier;

    u32 lcr;

    u32 mcr;

    u32 lsr;

    u32 msr;

    u32 scratch;

    u32 cntl;

    u32 stat;

    u32 baud;

};

​

#define BCM283X_MU_LCR_DATA_SIZE_8  3

​

#define BCM283X_MU_LSR_TX_IDLE      BIT(6)

/* This actually means not full, but is named not empty in the docs */

#define BCM283X_MU_LSR_TX_EMPTY     BIT(5)

#define BCM283X_MU_LSR_RX_READY     BIT(0)

​

struct bcm283x_mu_priv {

    struct bcm283x_mu_regs *regs;

};

​

static int bcm283x_mu_serial_getc(struct udevice *dev);

​

static int bcm283x_mu_serial_setbrg(struct udevice *dev, int baudrate)

{

    struct bcm283x_mu_serial_platdata *plat = dev_get_platdata(dev);

    struct bcm283x_mu_priv *priv = dev_get_priv(dev);

    struct bcm283x_mu_regs *regs = priv->regs;

    u32 divider;

​

    if (plat->skip_init)

        goto out;

​

    divider = plat->clock / (baudrate * 8);

​

    writel(BCM283X_MU_LCR_DATA_SIZE_8, &regs->lcr);

    writel(divider - 1, &regs->baud);

​

out:

    /* Flush the RX queue - all data in there is bogus */

    while (bcm283x_mu_serial_getc(dev) != -EAGAIN) ;

​

    return 0;

}

​

static int bcm283x_mu_serial_probe(struct udevice *dev)

{

    struct bcm283x_mu_serial_platdata *plat = dev_get_platdata(dev);

    struct bcm283x_mu_priv *priv = dev_get_priv(dev);

​

    priv->regs = (struct bcm283x_mu_regs *)plat->base;

​

    return 0;

}

​

static int bcm283x_mu_serial_getc(struct udevice *dev)

{

    struct bcm283x_mu_priv *priv = dev_get_priv(dev);

    struct bcm283x_mu_regs *regs = priv->regs;

    u32 data;

​