[U-Boot] [PATCH 1/7] mx25: Fix decode_pll

Benoît Thébaudeau
2012-09-27T20:26:54Z

The MFN bit-field of the PLL registers represents a signed value. See the
reference manual.

Signed-off-by: Beno?t Th?baudeau <benoit.thebaudeau@advansee.com>
Cc: Stefano Babic <sbabic@denx.de>
---
.../arch/arm/cpu/arm926ejs/mx25/generic.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)

diff --git u-boot-imx-e1eb75b.orig/arch/arm/cpu/arm926ejs/mx25/generic.c u-boot-imx-e1eb75b/arch/arm/cpu/arm926ejs/mx25/generic.c
index 90e584a..2283a89 100644
--- u-boot-imx-e1eb75b.orig/arch/arm/cpu/arm926ejs/mx25/generic.c
+++ u-boot-imx-e1eb75b/arch/arm/cpu/arm926ejs/mx25/generic.c
@@ -48,7 +48,7 @@ static unsigned int imx_decode_pll(unsigned int pll, unsigned int f_ref)
{
unsigned int mfi = (pll >> CCM_PLL_MFI_SHIFT)
& CCM_PLL_MFI_MASK;
- unsigned int mfn = (pll >> CCM_PLL_MFN_SHIFT)
+ int mfn = (pll >> CCM_PLL_MFN_SHIFT)
& CCM_PLL_MFN_MASK;
unsigned int mfd = (pll >> CCM_PLL_MFD_SHIFT)
& CCM_PLL_MFD_MASK;
@@ -56,9 +56,12 @@ static unsigned int imx_decode_pll(unsigned int pll, unsigned int f_ref)
& CCM_PLL_PD_MASK;

mfi = mfi <= 5 ? 5 : mfi;
+ mfn = mfn >= 512 ? mfn - 1024 : mfn;
+ mfd += 1;
+ pd += 1;

- return lldiv(2 * (u64) f_ref * (mfi * (mfd + 1) + mfn),
- (mfd + 1) * (pd + 1));
+ return lldiv(2 * (u64) f_ref * (mfi * mfd + mfn),
+ mfd * pd);
}

static ulong imx_get_mpllclk(void)