Re: Re: EPIC Vs OpenPIC (RFC)

Somehow I feel that Patching or changing
the openPIC code would make it shabby.
 Why should we change open_pic code,
just because that EPIC is non-conforming ?
The best is to rewrite open_pic code for
EPIC. ( ofcourse, we can reuse code. )
 I dont find anything wrong with open_pic
interface. If people dont follow standards,
we dont make standards comply with them. We
make them comply with standards.

Sarnath

On Sat, 03 Nov 2001 Dag Nygren wrote :

quoted

Mark A. Greer wrote:


This is along the lines that I was thinking except

add a struct member to specify

quoted

whether edge or level sensitive--i.e., separate

members for hi/lo and edge/level

Actually this evolved after I posted it :-), after I
started
to modify open_pic.c

quoted

What exactly is the "IrqEnable" for?  Is this so you

can set up the IRQ but not

quoted

enable it?  Then the driver can enable it later and

its set up correctly (e.g.,

quoted

I2C)??

Not really, it was more or less a mistake in the first
draft. Would there be a
need
for that ?

quoted

Doesn't the new struct eliminate the need for

"RegOffset"?

Have to think about that when implementing the stuff.

quoted

 And as you noted,
"programmer_switch_irq" probably isn't needed either.

 Right?

Yep, and I also came up with another scheme for the
cascading as the
special handling for chrp is actually.....drum roll....
a cascade!
And it would remove the i8259 refs from the openpic
stuff.

quoted

If you're up to it, how about implementing, testing,

then posting a patch for

quoted

everyone to check out??

I'm trying, but I am a bit scared of destroying too
much of the open_pic
code...

Here is the newest suggestion for that interface:

typedef enum irq_polarity_en {
    OP_IRQ_POS = 1,
    OP_IRQ_NEG = 0
} irq_polarity_type;

typedef enum irq_sense_en {
    OP_IRQ_LEVEL = 1,
    OP_IRQ_EDGE  = 0
} irq_sense_type;

typedef struct op

         PICIrq;

    u_int               Vector;
    u_char              Priority;
    irq_sense_type      IrqSense;
    irq_polarity_type   IrqPolarity;
    irq_polarity_type   IrqPolarity;
    int                 (*CascadeHandler)();
} openpic_irq_def;

typedef struct openpic_def_str {
    struct OpenPIC  *OpenPIC_Addr;
    int             main_pic;
    u_char          RegOffset; /* 0 for "standard", 16
for MPC107 */
    int             programmer_switch_irq;
    openpic_irq_def *IRQdef;    /* The lovest vector
first in the table !!! */
} openpic_def;

Comments?


Dag

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