[PATCH] ARM: PL330: Accept revisions of the dmac

[Jassi Brar]

On Mon, Sep 6, 2010 at 5:35 PM, Linus Walleij
<linus.ml.walleij at gmail.com> wrote:
> 2010/9/5 Jassi Brar <jassisinghbrar at gmail.com>:
>> [Me]
>>> Jassi, this kind of macros already exist in <linux/amba/bus.h>
>>> can't you just #include that and use these instead?
>> You mean to use amba_config/rev et al ?
>>
>> But they work on struct amba_device *, and I have to form those
>> structs just to make use of the macros.
>
> Ah I get it...
>
> But maybe we should refactor <linux/amba/bus.h> then?
> Something like this:
>
> From: Linus Walleij <linus.walleij at stericsson.com>
> Date: Mon, 6 Sep 2010 10:29:26 +0200
> Subject: [PATCH] ARM: move the PrimeCell IDs to use macros
>
> This make four macros for the PrimeCell ID register available to
> drivers that use them witout using the PrimeCell/AMBA bus
> abstraction and struct amba_device. It also moves the magic
> PrimeCell CID "B105F00D" to the bus.h header file.
>
> Signed-off-by: Linus Walleij <linus.walleij at stericsson.com>
> ---
>  drivers/amba/bus.c       |    2 +-
>  include/linux/amba/bus.h |   15 +++++++++++----
>  2 files changed, 12 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/amba/bus.c b/drivers/amba/bus.c
> index d31590e..2737b97 100644
> --- a/drivers/amba/bus.c
> +++ b/drivers/amba/bus.c
> @@ -298,7 +298,7 @@ int amba_device_register(struct amba_device *dev,
> struct resource *parent)
>
>                amba_put_disable_pclk(dev);
>
> -               if (cid == 0xb105f00d)
> +               if (cid == AMBA_CID)
>                        dev->periphid = pid;
>
>                if (!dev->periphid)
> diff --git a/include/linux/amba/bus.h b/include/linux/amba/bus.h
> index b0c1740..4c0f5a3 100644
> --- a/include/linux/amba/bus.h
> +++ b/include/linux/amba/bus.h
> @@ -20,6 +20,7 @@
>  #include <linux/resource.h>
>
>  #define AMBA_NR_IRQS   2
> +#define AMBA_CID       0xb105f00d
>
>  struct clk;
>
> @@ -70,9 +71,15 @@ void amba_release_regions(struct amba_device *);
>  #define amba_pclk_disable(d)   \
>        do { if (!IS_ERR((d)->pclk)) clk_disable((d)->pclk); } while (0)
>
> -#define amba_config(d) (((d)->periphid >> 24) & 0xff)
> -#define amba_rev(d)    (((d)->periphid >> 20) & 0x0f)
> -#define amba_manf(d)   (((d)->periphid >> 12) & 0xff)
> -#define amba_part(d)   ((d)->periphid & 0xfff)
> +/* Some drivers don't use the struct amba_device */
> +#define AMBA_CONFIG_BITS(a) ((a >> 24) & 0xff)
> +#define AMBA_REV_BITS(a) ((a >> 20) & 0x0f)
> +#define AMBA_MANF_BITS(a) ((a >> 12) & 0xff)
> +#define AMBA_PART_BITS(a) (a & 0xfff)
> +
> +#define amba_config(d) AMBA_CONFIG_BITS((d)->periphid)
> +#define amba_rev(d)    AMBA_REV_BITS((d)->periphid)
> +#define amba_manf(d)   AMBA_MANF_BITS((d)->periphid)
> +#define amba_part(d)   AMBA_PART_BITS((d)->periphid)

Sorry I missed that I need to read periph_id[0,3] regs and form
Peripheral-ID from them,
These macros do the reverse - extract fields from the Peripheral-ID.
btw, you might want to close argument 'a' in parens as in ((a) & 0xfff) ?

........

>
> enum amba_vendor {
>        AMBA_VENDOR_ARM = 0x41,
>        AMBA_VENDOR_ST = 0x80,
> };
>
> What byte value is Samsung using for vendor?
I haven't come across it in any device so far. I have only seen
ARM IPs being used.