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[ARM] MXC: Use a single function for decoding a PLL

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We had 3 versions of this function in clock support for MX1/2/3
Use a single one instead. I picked the one from the MX3 as it seems
to calculate more accurate as the other ones. Also, on MX27 and MX31 mfn
can be negative, this hasn't been handled correctly on MX27 since now.

This patch has been tested on MX27 and MX31 and produces the same clock
frequencies for me.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
This commit is contained in:
Sascha Hauer
2009-01-26 15:41:16 +01:00
parent 5512e88f3a
commit a2865197a5
5 changed files with 57 additions and 88 deletions
Download Patch File Download Diff File Expand all files Collapse all files

26
arch/arm/mach-mx3/clock.c
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@@ -158,10 +158,8 @@ static int _clk_pll_set_rate(struct clk *clk, unsigned long rate)
static unsigned long _clk_pll_get_rate(struct clk *clk)
{
long mfi, mfn, mfd, pdf, ref_clk, mfn_abs;
unsigned long reg, ccmr;
s64 temp;
unsigned int prcs;
unsigned int prcs, ref_clk;
ccmr = __raw_readl(MXC_CCM_CCMR);
prcs = (ccmr & MXC_CCM_CCMR_PRCS_MASK) >> MXC_CCM_CCMR_PRCS_OFFSET;
@@ -185,27 +183,7 @@ static unsigned long _clk_pll_get_rate(struct clk *clk)
return 0;
}
pdf = (reg & MXC_CCM_PCTL_PD_MASK) >> MXC_CCM_PCTL_PD_OFFSET;
mfd = (reg & MXC_CCM_PCTL_MFD_MASK) >> MXC_CCM_PCTL_MFD_OFFSET;
mfi = (reg & MXC_CCM_PCTL_MFI_MASK) >> MXC_CCM_PCTL_MFI_OFFSET;
mfi = (mfi <= 5) ? 5 : mfi;
mfn = mfn_abs = reg & MXC_CCM_PCTL_MFN_MASK;
if (mfn >= 0x200) {
mfn |= 0xFFFFFE00;
mfn_abs = -mfn;
}
ref_clk *= 2;
ref_clk /= pdf + 1;
temp = (u64) ref_clk * mfn_abs;
do_div(temp, mfd + 1);
if (mfn < 0)
temp = -temp;
temp = (ref_clk * mfi) + temp;
return temp;
return mxc_decode_pll(reg, ref_clk);
}
static int _clk_usb_pll_enable(struct clk *clk)