| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Date: Tue, 3 May 2011 13:41:19 -0600
From: Grant Likely <grant.likely@...retlab.ca>
To: Jamie Iles <jamie@...ieiles.com>
Cc: linux-kernel@...r.kernel.org, linux@....linux.org.uk,
tglx@...utronix.de, cbouatmailru@...il.com, arnd@...db.de,
nico@...xnic.net
Subject: Re: [PATCHv3 1/7] basic_mmio_gpio: remove runtime width/endianness
evaluation
On Mon, Apr 11, 2011 at 12:21:48PM +0100, Jamie Iles wrote:
> Remove endianness/width calculations at runtime by installing function
> pointers for bit-to-mask conversion and register accessors.
>
> Reported-by: Thomas Gleixner <tglx@...utronix.de>
> Signed-off-by: Jamie Iles <jamie@...ieiles.com>
> Acked-by: Anton Vorontsov <cbouatmailru@...il.com>
> Cc: Grant Likely <grant.likely@...retlab.ca>
Merged, thanks.
g.
> ---
> drivers/gpio/basic_mmio_gpio.c | 136 +++++++++++++++++++++++++++-------------
> 1 files changed, 92 insertions(+), 44 deletions(-)
>
> diff --git a/drivers/gpio/basic_mmio_gpio.c b/drivers/gpio/basic_mmio_gpio.c
> index 3addea6..e935a24 100644
> --- a/drivers/gpio/basic_mmio_gpio.c
> +++ b/drivers/gpio/basic_mmio_gpio.c
> @@ -63,6 +63,10 @@ o ` ~~~~\___/~~~~ ` controller in FPGA is ,.`
>
> struct bgpio_chip {
> struct gpio_chip gc;
> +
> + unsigned long (*read_reg)(void __iomem *reg);
> + void (*write_reg)(void __iomem *reg, unsigned long data);
> +
> void __iomem *reg_dat;
> void __iomem *reg_set;
> void __iomem *reg_clr;
> @@ -74,7 +78,7 @@ struct bgpio_chip {
> * Some GPIO controllers work with the big-endian bits notation,
> * e.g. in a 8-bits register, GPIO7 is the least significant bit.
> */
> - int big_endian_bits;
> + unsigned long (*pin2mask)(struct bgpio_chip *bgc, unsigned int pin);
>
> /*
> * Used to lock bgpio_chip->data. Also, this is needed to keep
> @@ -91,70 +95,77 @@ static struct bgpio_chip *to_bgpio_chip(struct gpio_chip *gc)
> return container_of(gc, struct bgpio_chip, gc);
> }
>
> -static unsigned long bgpio_in(struct bgpio_chip *bgc)
> +static void bgpio_write8(void __iomem *reg, unsigned long data)
> {
> - switch (bgc->bits) {
> - case 8:
> - return __raw_readb(bgc->reg_dat);
> - case 16:
> - return __raw_readw(bgc->reg_dat);
> - case 32:
> - return __raw_readl(bgc->reg_dat);
> -#if BITS_PER_LONG >= 64
> - case 64:
> - return __raw_readq(bgc->reg_dat);
> -#endif
> - }
> - return -EINVAL;
> + __raw_writeb(data, reg);
> }
>
> -static void bgpio_out(struct bgpio_chip *bgc, void __iomem *reg,
> - unsigned long data)
> +static unsigned long bgpio_read8(void __iomem *reg)
> {
> - switch (bgc->bits) {
> - case 8:
> - __raw_writeb(data, reg);
> - return;
> - case 16:
> - __raw_writew(data, reg);
> - return;
> - case 32:
> - __raw_writel(data, reg);
> - return;
> + return __raw_readb(reg);
> +}
> +
> +static void bgpio_write16(void __iomem *reg, unsigned long data)
> +{
> + __raw_writew(data, reg);
> +}
> +
> +static unsigned long bgpio_read16(void __iomem *reg)
> +{
> + return __raw_readw(reg);
> +}
> +
> +static void bgpio_write32(void __iomem *reg, unsigned long data)
> +{
> + __raw_writel(data, reg);
> +}
> +
> +static unsigned long bgpio_read32(void __iomem *reg)
> +{
> + return __raw_readl(reg);
> +}
> +
> #if BITS_PER_LONG >= 64
> - case 64:
> - __raw_writeq(data, reg);
> - return;
> -#endif
> - }
> +static void bgpio_write64(void __iomem *reg, unsigned long data)
> +{
> + __raw_writeq(data, reg);
> }
>
> +static unsigned long bgpio_read64(void __iomem *reg)
> +{
> + return __raw_readq(reg);
> +}
> +#endif /* BITS_PER_LONG >= 64 */
> +
> static unsigned long bgpio_pin2mask(struct bgpio_chip *bgc, unsigned int pin)
> {
> - if (bgc->big_endian_bits)
> - return 1 << (bgc->bits - 1 - pin);
> - else
> - return 1 << pin;
> + return 1 << pin;
> +}
> +
> +static unsigned long bgpio_pin2mask_be(struct bgpio_chip *bgc,
> + unsigned int pin)
> +{
> + return 1 << (bgc->bits - 1 - pin);
> }
>
> static int bgpio_get(struct gpio_chip *gc, unsigned int gpio)
> {
> struct bgpio_chip *bgc = to_bgpio_chip(gc);
>
> - return bgpio_in(bgc) & bgpio_pin2mask(bgc, gpio);
> + return bgc->read_reg(bgc->reg_dat) & bgc->pin2mask(bgc, gpio);
> }
>
> static void bgpio_set(struct gpio_chip *gc, unsigned int gpio, int val)
> {
> struct bgpio_chip *bgc = to_bgpio_chip(gc);
> - unsigned long mask = bgpio_pin2mask(bgc, gpio);
> + unsigned long mask = bgc->pin2mask(bgc, gpio);
> unsigned long flags;
>
> if (bgc->reg_set) {
> if (val)
> - bgpio_out(bgc, bgc->reg_set, mask);
> + bgc->write_reg(bgc->reg_set, mask);
> else
> - bgpio_out(bgc, bgc->reg_clr, mask);
> + bgc->write_reg(bgc->reg_clr, mask);
> return;
> }
>
> @@ -165,7 +176,7 @@ static void bgpio_set(struct gpio_chip *gc, unsigned int gpio, int val)
> else
> bgc->data &= ~mask;
>
> - bgpio_out(bgc, bgc->reg_dat, bgc->data);
> + bgc->write_reg(bgc->reg_dat, bgc->data);
>
> spin_unlock_irqrestore(&bgc->lock, flags);
> }
> @@ -181,9 +192,44 @@ static int bgpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
> return 0;
> }
>
> -static int __devinit bgpio_probe(struct platform_device *pdev)
> +static int bgpio_setup_accessors(struct platform_device *pdev,
> + struct bgpio_chip *bgc)
> {
> const struct platform_device_id *platid = platform_get_device_id(pdev);
> +
> + switch (bgc->bits) {
> + case 8:
> + bgc->read_reg = bgpio_read8;
> + bgc->write_reg = bgpio_write8;
> + break;
> + case 16:
> + bgc->read_reg = bgpio_read16;
> + bgc->write_reg = bgpio_write16;
> + break;
> + case 32:
> + bgc->read_reg = bgpio_read32;
> + bgc->write_reg = bgpio_write32;
> + break;
> +#if BITS_PER_LONG >= 64
> + case 64:
> + bgc->read_reg = bgpio_read64;
> + bgc->write_reg = bgpio_write64;
> + break;
> +#endif /* BITS_PER_LONG >= 64 */
> + default:
> + dev_err(&pdev->dev, "unsupported data width %u bits\n",
> + bgc->bits);
> + return -EINVAL;
> + }
> +
> + bgc->pin2mask = strcmp(platid->name, "basic-mmio-gpio-be") ?
> + bgpio_pin2mask : bgpio_pin2mask_be;
> +
> + return 0;
> +}
> +
> +static int __devinit bgpio_probe(struct platform_device *pdev)
> +{
> struct device *dev = &pdev->dev;
> struct bgpio_pdata *pdata = dev_get_platdata(dev);
> struct bgpio_chip *bgc;
> @@ -232,9 +278,11 @@ static int __devinit bgpio_probe(struct platform_device *pdev)
> spin_lock_init(&bgc->lock);
>
> bgc->bits = bits;
> - bgc->big_endian_bits = !strcmp(platid->name, "basic-mmio-gpio-be");
> - bgc->data = bgpio_in(bgc);
> + ret = bgpio_setup_accessors(pdev, bgc);
> + if (ret)
> + return ret;
>
> + bgc->data = bgc->read_reg(bgc->reg_dat);
> bgc->gc.ngpio = bits;
> bgc->gc.direction_input = bgpio_dir_in;
> bgc->gc.direction_output = bgpio_dir_out;
> --
> 1.7.4.2
>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists