RFC [PATCH 3/9] Added core lpc32xx architecture files

Russell King - ARM Linux linux at arm.linux.org.uk
Fri Nov 20 05:10:22 EST 2009


Thanks for posting these patches.

On Fri, Nov 20, 2009 at 02:11:21AM +0100, Kevin Wells wrote:
> +/*
> + * I2C busses
> + */
> +static void i2c_clock_get_name(char *name, int id)
> +{
> +       snprintf(name, 10, "i2c%d_ck", id);
> +}
> +
> +static int i2c_set_clock_run(struct platform_device *pdev)
> +{
> +       struct clk *clk;
> +       char name[10];
> +       int retval = 0;
> +
> +       i2c_clock_get_name(name, pdev->id);
> +       clk = clk_get(&pdev->dev, name);
> +       if (!IS_ERR(clk)) {
> +               clk_set_rate(clk, 1);
> +               clk_put(clk);
> +       } else
> +               retval = -ENOENT;
> +
> +       return retval;
> +}
> +
> +static int i2c_set_clock_stop(struct platform_device *pdev)
> +{
> +       struct clk *clk;
> +       char name[10];
> +       int retval = 0;
> +
> +       i2c_clock_get_name(name, pdev->id);
> +       clk = clk_get(&pdev->dev, name);
> +       if (!IS_ERR(clk)) {
> +               clk_set_rate(clk, 0);
> +               clk_put(clk);
> +       } else
> +               retval = -ENOENT;
> +
> +       return retval;
> +}

This is interesting for the following reasons:

1. you don't need to generate unique clock names based on the device.
2. you should be using clk_enable() and clk_disable() to turn the
   turn the clock on and off, rather than clk_set_rate()
3. I can see no reason why these should not be in the I2C driver itself.

I think I know why this is happening, which is because mach-pnx4008
didn't get properly reviewed in these respects before it went in.

What I would like to do is to see whether we can get the existing PNX I2C
driver fixed up before we merge this; essentially I want to stop the
current issue getting any bigger than it currently is, thereby requiring
even more work to resolve.

> +static inline void __set_gpio_dir_p012(struct lpc32xx_gpio_chip *group,
> +       unsigned pin, int input)
> +{
> +       if (input)
> +               writel((1 << pin), group->gpio_grp->dir_clr);
> +       else
> +               writel((1 << pin), group->gpio_grp->dir_set);

Parens are not required around function (or macro) arguments when calling
them.  (In the case of macros, they should always internally use parens
around arguments.  IOW:

#define foo(x, y)	((x) * (y))

so that foo(5 + 6, 1 + 2) results in 33 and not 13.)

Something else you may wish to consider is changing the 'inline' to
'noinline' temporarily, and check the assembly.  I suspect writing these
functions like the following will result in smaller and faster code:

	void __iomem *reg;

	if (input)
		reg = group->gpio_grp->dir_clr;
	else
		reg = group->gpio_grp->dir_set;

	writel(1 << pin, reg);

> diff --git a/arch/arm/mach-lpc32xx/irq.c b/arch/arm/mach-lpc32xx/irq.c
> new file mode 100644
> index 0000000..44772ce
> --- /dev/null
> +++ b/arch/arm/mach-lpc32xx/irq.c
> @@ -0,0 +1,247 @@
> +/*
> + *  linux/arch/arm/mach-lpc32xx/irq.c
> + *
> + *  Copyright (C) 2009 NXP Semiconductors
> + *
> + * 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 <linux/kernel.h>
> +#include <linux/types.h>
> +#include <linux/mm.h>
> +#include <linux/interrupt.h>
> +#include <linux/list.h>
> +#include <linux/init.h>
> +#include <linux/ioport.h>
> +#include <linux/device.h>
> +#include <linux/irq.h>
> +#include <mach/hardware.h>
> +#include <asm/io.h>

Should be linux/io.h

> +#include <asm/setup.h>
> +#include <asm/mach-types.h>
> +#include <asm/pgtable.h>
> +#include <asm/page.h>
> +#include <asm/system.h>
> +#include <asm/mach/arch.h>
> +#include <asm/mach/irq.h>
> +#include <asm/mach/map.h>
> +#include <mach/irqs.h>
> +#include <mach/platform.h>

Are you sure all these includes are needed?  Please eliminate unnecessary
includes.

> diff --git a/arch/arm/mach-lpc32xx/serial.c b/arch/arm/mach-lpc32xx/serial.c
> new file mode 100644
> index 0000000..e2bfe49
> --- /dev/null
> +++ b/arch/arm/mach-lpc32xx/serial.c
> @@ -0,0 +1,211 @@
> +/*
> + *  linux/arch/arm/mach-lpc32xx/serial.c
> + *
> + *  Copyright (C) 2009 NXP Semiconductors
> + *
> + * 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 <linux/kernel.h>
> +#include <linux/types.h>
> +#include <linux/serial.h>
> +#include <linux/serial_core.h>
> +#include <linux/serial_reg.h>
> +#include <linux/serial_8250.h>
> +#include <linux/clk.h>
> +
> +#include <mach/platform.h>
> +#include <mach/io.h>

Should be linux/io.h

> +#include "common.h"
> +
> +#define UARTCTL_CLKMODE(x)     (x + 0x04)
> +
> +/* Standard 8250/16550 compatible serial ports */
> +static struct plat_serial8250_port serial_std_platform_data[] = {
> +#if defined (CONFIG_MACH_LPC32XX_UART5_ENABLE)
> +       {
> +               .membase        = (void *) io_p2v(UART5_BASE),
> +               .mapbase        = UART5_BASE,
> +               .irq            = IRQ_UART_IIR5,
> +               .uartclk        = MAIN_OSC_FREQ,
> +               .regshift       = 2,
> +               .iotype         = UPIO_MEM32,
> +               .flags          = UPF_BOOT_AUTOCONF | UPF_BUGGY_UART |
> +                                       UPF_SKIP_TEST,
> +       },
> +#endif
> +#if defined (CONFIG_MACH_LPC32XX_UART3_ENABLE)
> +       {
> +               .membase        = (void *) io_p2v(UART3_BASE),
> +               .mapbase        = UART3_BASE,
> +               .irq            = IRQ_UART_IIR3,
> +               .uartclk        = MAIN_OSC_FREQ,
> +               .regshift       = 2,
> +               .iotype         = UPIO_MEM32,
> +               .flags          = UPF_BOOT_AUTOCONF | UPF_BUGGY_UART |
> +                                       UPF_SKIP_TEST,
> +       },
> +#endif
> +#if defined (CONFIG_MACH_LPC32XX_UART4_ENABLE)
> +       {
> +               .membase        = (void *) io_p2v(UART4_BASE),
> +               .mapbase        = UART4_BASE,
> +               .irq            = IRQ_UART_IIR4,
> +               .uartclk        = MAIN_OSC_FREQ,
> +               .regshift       = 2,
> +               .iotype         = UPIO_MEM32,
> +               .flags          = UPF_BOOT_AUTOCONF | UPF_BUGGY_UART |
> +                                       UPF_SKIP_TEST,
> +       },
> +#endif
> +#if defined (CONFIG_MACH_LPC32XX_UART6_ENABLE)
> +       {
> +               .membase        = (void *) io_p2v(UART6_BASE),
> +               .mapbase        = UART6_BASE,
> +               .irq            = IRQ_UART_IIR6,
> +               .uartclk        = MAIN_OSC_FREQ,
> +               .regshift       = 2,
> +               .iotype         = UPIO_MEM32,
> +               .flags          = UPF_BOOT_AUTOCONF | UPF_BUGGY_UART |
> +                                       UPF_SKIP_TEST,
> +       },
> +#endif
> +       { },
> +};
> +
> +static struct platform_device serial_std_platform_device = {
> +       .name                   = "serial8250",
> +       .id                     = 0,
> +       .dev                    = {
> +               .platform_data  = serial_std_platform_data,
> +       },
> +};
> +
> +static struct platform_device* lpc32xx_serial_devs[] = {
> +       &serial_std_platform_device,
> +};
> +
> +void __init serial_init(void)
> +{
> +       u32 tmp, rate;
> +       struct clk *clk;
> +       int i;
> +
> +       /* Get the current peripheral clock - if the clock can't be fetched,
> +          use the main oscillator as the base clock. */
> +       clk = clk_get(NULL, "pclk_ck");
> +       if (IS_ERR(clk))
> +               rate = MAIN_OSC_FREQ;
> +       else
> +       {
> +               rate = clk_get_rate(clk);
> +               clk_put(clk);
> +       }
> +       if (rate == 0)
> +               rate = MAIN_OSC_FREQ;

Similar concerns about clk API here.

> diff --git a/arch/arm/mach-lpc32xx/timer.c b/arch/arm/mach-lpc32xx/timer.c
> new file mode 100644
> index 0000000..0f434b0
> --- /dev/null
> +++ b/arch/arm/mach-lpc32xx/timer.c
> @@ -0,0 +1,194 @@
> +/*
> + *  linux/arch/arm/mach-lpc32xx/timer.c
> + *
> + *  Copyright (C) 2009 NXP Semiconductors
> + *  Copyright (C) 2009 Fontys University of Applied Sciences, Eindhoven
> + *                     Ed Schouten <e.schouten at fontys.nl>
> + *                     Laurens Timmermans <l.timmermans at fontys.nl>
> + *
> + * 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 <linux/module.h>
> +#include <linux/kernel.h>
> +#include <linux/interrupt.h>
> +#include <linux/irq.h>
> +#include <linux/time.h>
> +#include <linux/clk.h>
> +#include <linux/err.h>
> +#include <linux/clockchips.h>
> +#include <linux/clocksource.h>
> +
> +#include <mach/hardware.h>
> +#include <asm/io.h>

linux/io.h

> +#include <asm/irq.h>
> +
> +#include <asm/mach/time.h>
> +
> +#include <mach/platform.h>
> +#include <mach/clock.h>
> +#include "common.h"
> +
> +#define TIMER0_IOBASE io_p2v(TIMER0_BASE)
> +#define TIMER1_IOBASE io_p2v(TIMER1_BASE)
> +
> +extern int clk_is_sysclk_mainosc(void);
> +extern u32 local_clk_get_pllrate_from_reg(u32 inputclk, u32 regval);
> +extern u32 clk_get_pclk_div(void);

externs should be in a header file (common.h ?).

> +
> +static struct clock_event_device lpc32xx_clkevt;

I don't think this is required.




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