diff options
| author | Stefano Babic <sbabic@denx.de> | 2012-02-22 00:24:38 +0000 |
|---|---|---|
| committer | John Rigby <john.rigby@linaro.org> | 2012-05-04 16:28:46 -0600 |
| commit | 8a409792b7309d23998cb1d70c66ec96a788784b (patch) | |
| tree | 70304068cdfd4643d8e3a683833ec470828eb4eb /arch/arm/cpu/armv7/mx5/clock.c | |
| parent | ad7d899648147f8a65ee36b54d5c61fb3b374bd8 (diff) | |
MX53: add function to set SATA clock to internal
The MX53 SATA interface can use an internal clock (USB PHY1)
instead of an external clock. This is an undocumented feature, but used
on most Freescale's evaluation boards, such as MX53-loco.
As stated by Freescale's support:
Fuses (but not pins) may be used to configure SATA clocks.
Particularly the i.MX53 Fuse_Map contains the next information
about configuring SATA clocks :
SATA_ALT_REF_CLK[1:0] (offset 0x180C)
'00' - 100MHz (External)
'01' - 50MHz (External)
'10' - 120MHz, internal (USB PHY)
'11' - Reserved
Signed-off-by: Stefano Babic <sbabic@denx.de>
CC: Fabio Estevam <fabio.estevam@freescale.com>
Diffstat (limited to 'arch/arm/cpu/armv7/mx5/clock.c')
| -rw-r--r-- | arch/arm/cpu/armv7/mx5/clock.c | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/arch/arm/cpu/armv7/mx5/clock.c b/arch/arm/cpu/armv7/mx5/clock.c index 8f8d01c26..d769a4d77 100644 --- a/arch/arm/cpu/armv7/mx5/clock.c +++ b/arch/arm/cpu/armv7/mx5/clock.c @@ -399,6 +399,30 @@ u32 imx_get_fecclk(void) return mxc_get_clock(MXC_IPG_CLK); } +#ifdef CONFIG_MX53 +/* + * The clock for the external interface can be set to use internal clock + * if fuse bank 4, row 3, bit 2 is set. + * This is an undocumented feature and it was confirmed by Freescale's support: + * Fuses (but not pins) may be used to configure SATA clocks. + * Particularly the i.MX53 Fuse_Map contains the next information + * about configuring SATA clocks : SATA_ALT_REF_CLK[1:0] (offset 0x180C) + * '00' - 100MHz (External) + * '01' - 50MHz (External) + * '10' - 120MHz, internal (USB PHY) + * '11' - Reserved +*/ +void mxc_set_sata_internal_clock(void) +{ + u32 *tmp_base = + (u32 *)(IIM_BASE_ADDR + 0x180c); + + set_usb_phy1_clk(); + + writel((readl(tmp_base) & (~0x7)) | 0x4, tmp_base); +} +#endif + /* * Dump some core clockes. */ |