[PATCH v4 01/13] OMAP: DMA: Replace read/write macros with functions

Tony Lindgren tony at atomide.com
Mon Nov 8 19:40:45 EST 2010


Hi,

* G, Manjunath Kondaiah <manjugk at ti.com> [101108 05:58]:

> +static u16 reg_map_omap1[] = {
> +	[GCR1]		= 0x400,
> +	[GSCR]		= 0x404,
> +	[GRST]		= 0x408,
...
> +};

The above you should move to mach-omap1/dma.c and pass it in the init
function to plat-omap/dma.c. Let's try to make the common code clean
of omap1/2/3/4 specific data.

> +static u16 reg_map_omap2[] = {
> +	[REVISION]		= 0x00,
> +	[GCR2]			= 0x78,
> +	[IRQSTATUS_L0]		= 0x08,
...
> +};

And the above you should move to mach-omap2/dma.c.

It's OK to do it in a later patch if you prefer that, but in that case
the patch description here should mention it.

>  	if (cpu_class_is_omap2() && dma_trigger) {
>  		u32 val;
>  
> -		val = dma_read(CCR(lch));
> +		l = dma_read(CSDP2, lch);
> +		l &= ~0x03;
> +		l |= data_type;
> +		dma_write(l, CSDP2, lch);
> +
> +		val = dma_read(CCR2, lch);

This seems to be doing more than just change the read function?

Please keep any functional changes separate. Let's first get the
hwmod based initialization done without any functional changes
to avoid breaking things.
  
> @@ -475,11 +654,19 @@ void omap_set_dma_src_data_pack(int lch, int enable)
>  {
>  	u32 l;
>  
> -	l = dma_read(CSDP(lch));
> +	if (cpu_class_is_omap1())
> +		l = dma_read(CSDP1, lch);
> +	else
> +		l = dma_read(CSDP2, lch);
> +
>  	l &= ~(1 << 6);
>  	if (enable)
>  		l |= (1 << 6);
> -	dma_write(l, CSDP(lch));
> +
> +	if (cpu_class_is_omap1())
> +		dma_write(l, CSDP1, lch);
> +	else
> +		dma_write(l, CSDP2, lch);
>  }

Since you now have the register mapping table, why do you still need
to separate between CSDP1 and CSDP2 registers?

You should now be able to call them just CSDP, and then the register
can be mapped to the right offset for omap1 and omap2+.

So this should be just:

void omap_set_dma_src_data_pack(int lch, int enable)
{
	u32 l;

	l = p->dma_read(CSDP, lch);
	l &= ~(1 << 6);
	if (enable)
		l |= (1 << 6);
	p->dma_write(l, CSDP, lch);
}

Please check the other functions for this too, that should
leave out quite a bit of if cpu_class_is_omap1 clutter.

And looking at it more, you should only have one enum for the
registers, not separate enum for both omap1 and omap2+. The
enum should be common for all of them. If needed, the enum
should be separate for common register and channel specific
registers.

Some 32-bit registers for omap1 have the lower and upper registers,
because of the 16-bit register access. So those still need to be
handled separately for omap1. That can be handled automatically
for omap1 (untested):

static inline u32 omap1_dma_read(int reg, int lch)
{
	u32 va, val, ch_offset = 0;

	if (reg > OMAP1_CH_COMMON_START)
		ch_offset = 0x40 * lch;

	va = dma_base + reg_map_omap1[reg] + ch_offset;
	val = __raw_readw(va);

	/* Some channel registers also have an associated upper register */
	if (reg >= CSSA) {
		16 upper = __raw_readw(va + 2);
		val |= (upper << 16);
	}

	return val;
}
...

Regards,

Tony



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