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authorGiuseppe CAVALLARO <peppe.cavallaro@st.com>2014-08-27 10:37:49 +0200
committerDavid S. Miller <davem@davemloft.net>2014-08-29 19:54:36 -0700
commit5566401f2f10556776fd199c11d6a02a5e0b7b95 (patch)
treeb9127a13d0c5df4939c72be2fc618e38e9afaf5c /Documentation
parent2b78d348f1bc3396ca1662c6a6177a7fb1ca62ff (diff)
stmmac: ptp: fix the reference clock
The PTP reference clock, used for setting the addend in the Timestamp Addend Register, was erroneously hard-coded (as reported in the databook just as example). The patch removes the macro named: STMMAC_SYSCLOCK and allows to use a reference clock (clk_ptp_ref_i) that can be passed from the platform. If not passed, the main driver clock will be used as default; note that this can be fine on some platforms. Note that, prior this patch, using the old STMMAC_SYSCLOCK on some platforms, as side effect, the ptp clock can move faster/slower than the system clock. Signed-off-by: Giuseppe Cavallaro <peppe.cavallaro@st.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/devicetree/bindings/net/stmmac.txt4
1 files changed, 4 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/net/stmmac.txt b/Documentation/devicetree/bindings/net/stmmac.txt
index 9b03c57563a..e45ac3f926b 100644
--- a/Documentation/devicetree/bindings/net/stmmac.txt
+++ b/Documentation/devicetree/bindings/net/stmmac.txt
@@ -39,6 +39,10 @@ Optional properties:
further clocks may be specified in derived bindings.
- clock-names: One name for each entry in the clocks property, the
first one should be "stmmaceth".
+- clk_ptp_ref: this is the PTP reference clock; in case of the PTP is
+ available this clock is used for programming the Timestamp Addend Register.
+ If not passed then the system clock will be used and this is fine on some
+ platforms.
Examples: