[U-Boot] [PATCH 3/5] vybrid: add uart driver support

[Wang Huan-B18965]

> On 12/04/2013 08:53, Alison Wang wrote:
> > This patch adds uart driver support for vybrid platform.
> >
> > Signed-off-by: TsiChung Liew <tsicliew at gmail.com>
> > Signed-off-by: Jason Jin <Jason.jin at freescale.com>
> > Signed-off-by: Alison Wang <b18965 at freescale.com>
> > ---
> 
> Hi Alison
> 
> > diff --git a/drivers/serial/serial_vybrid.c
> > b/drivers/serial/serial_vybrid.c new file mode 100644 index
> > 0000000..4dd9b52
> > --- /dev/null
> > +++ b/drivers/serial/serial_vybrid.c
> > @@ -0,0 +1,129 @@
> > +/*
> > + * Copyright 2012-2013 Freescale Semiconductor, Inc.
> > + *
> > + * This program is free software; you can redistribute it and/or
> > +modify
> > + * it under the terms of the GNU General Public License as published
> > +by
> > + * the Free Software Foundation; either version 2 of the License, or
> > + * (at your option) any later version.
> > + *
> > + * This program is distributed in the hope that it will be useful,
> > + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> > + * GNU General Public License for more details.
> > + *
> > + * You should have received a copy of the GNU General Public License
> > + * along with this program; if not, write to the Free Software
> > + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
> > +02111-1307  USA
> > + *
> > + */
> > +
> > +#include <common.h>
> > +#include <watchdog.h>
> > +#include <asm/io.h>
> > +#include <serial.h>
> > +#include <linux/compiler.h>
> > +#include <asm/arch/vybrid-regs.h>
> > +#include <asm/arch/serial-vybrid.h>
> > +#include <asm/arch/clock.h>
> > +
> > +#ifndef CONFIG_VYBRID_UART_BASE
> > +#error "define CONFIG_VYBRID_UART_BASE to use the VYBRID UART driver"
> > +#endif
> > +
> > +#define UART_CONSOLE	\
> > +		(CONFIG_VYBRID_UART_BASE + (CONFIG_SYS_UART_PORT * 0x1000))
> > +
> > +#ifdef CONFIG_SERIAL_MULTI
> > +#warning "Vybrid driver does not support MULTI serials."
> > +#endif
> > +
> > +DECLARE_GLOBAL_DATA_PTR;
> > +
> > +static void vybrid_serial_setbrg(void) {
> > +	u32 clk = vybrid_get_uartclk();
> > +	u16 sbr;
> > +
> > +	if (!gd->baudrate)
> > +		gd->baudrate = CONFIG_BAUDRATE;
> > +
> > +	sbr = (u16)(clk / (16 * gd->baudrate));
> > +	/* place adjustment later - n/32 BRFA */
> > +
> > +	out_8((UART_CONSOLE + UBDH), (sbr >> 8));
> > +	out_8((UART_CONSOLE + UBDL), (sbr & 0xFF)); }
> > +
> > +static int vybrid_serial_getc(void)
> > +{
> > +	while (!(in_8(UART_CONSOLE + US1) & US1_RDRF))
> > +		WATCHDOG_RESET();
> > +
> 
> Generally : do not use BASE + offset as here. Use C structures, instead.
> We have already ARM accessors (in8 is defined for powerpc). Use functions
> in io.h
[Alison Wang] Agree. I will modify to use C structures and use functions in io.h in the next version patches. Thanks a lot.
> 
> This driver is very simple, and it is similar to already implemented
> drivers. Sure that we cannot reuse other code ?
[Alison Wang] As they are different IPs, I don't think we can reuse the UART driver for I.MX family.
> 

Thanks!

Best Regards,
Alison Wang