Grant Likely wrote:
On Thu, Jul 31, 2008 at 11:22 AM, Wolfgang Grandegger <[EMAIL PROTECTED]> wrote:
Jon Smirl wrote:
On 7/31/08, Wolfgang Grandegger <[EMAIL PROTECTED]> wrote:
Grant Likely wrote:
On Fri, Jul 25, 2008 at 11:19:41AM -0500, Timur Tabi wrote:
Wolfgang Grandegger wrote:
I know but we still need an algorithm for MPC52xx and MPC82xx as well.
That's true, but I still think hard-coding values of DFSR and FDR in
the
device
tree is not a good way to do this.
I agree, it should encode real frequencies, not raw register values.
Digging deeper I'm frightened by plenty of platform specific code. We
would
need:
- one table of divider,fdr,dfsr values for the MPC82/3/5/6xx processors
(already available from Timur's U-Boot implementation)
- one table of divider,fdr values for the MPC5200 rev A.
- one table of divider,fdr values for the MPC5200 rev B.
(the Rev. B has two more pre-scaler bits).
Aren't the tables in the manual there just to make it easy for a human
to pick out the line they want? For a computer you'd program the
formula that was used to create the tables.
I have the formulas to create the tables, also for the MPC5200 Rev. A and B.
Oh, hey, even better.
That was not my point. I'm worried about arch specific code in i2c-mpc.c. It
should go somewhere to arch/powerpc.
i2c-mpc *is* arch specific. I really don't think you need to worry
about adding a block of code for each supported SoC family. Just
change the of_match table to look something like this:
static const struct of_device_id mpc_i2c_of_match[] = {
{.compatible = "fsl,mpc5200b-i2c", .data = fsl_i2c_mpc5200b_set_freq, },
{.compatible = "fsl,mpc5200-i2c", .data = fsl_i2c_mpc5200_set_freq, },
{.compatible = "fsl,mpc8260-i2c", .data = fsl_i2c_mpc8xxx_set_freq, },
{.compatible = "fsl,mpc8349-i2c", .data = fsl_i2c_mpc8xxx_set_freq, },
{.compatible = "fsl,mpc8540-i2c", .data = fsl_i2c_mpc8xxx_set_freq, },
{.compatible = "fsl,mpc8543-i2c", .data =
fsl_i2c_mpc8xxx_div2_set_freq, },
{.compatible = "fsl,mpc8544-i2c", .data =
fsl_i2c_mpc8xxx_div3_set_freq, },
/* keep this only for older device trees with some support
code to figure out
what .data should have pointed to. */
{.compatible = "fsl-i2c", },
{},
};
MODULE_DEVICE_TABLE(of, mpc_i2c_of_match);
Cool, this would also make the "dfsrr" property obsolete. Just the
MPC8544 needs more attention because the I2C clock can be programmed to
be freq/2 or freq/3.
Wolfgang.
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