ARM: tegra: define Tegra20 CAR binding

The Tegra20 CAR (Clock And Reset) Controller controls most aspects of
most clocks within Tegra20. The device tree binding models this as a
single monolithic clock provider, which exports many clocks. This reduces
the number of nodes needed in device tree to represent these clocks.

This binding is only useful for Tegra20; the set of clocks that exists on
Tegra30 is sufficiently different to merit its own binding.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Simon Glass <sjg@chromium.org>
[pgaikwad: Added mux clk ids and sorted CAR node]
Signed-off-by: Prashant Gaikwad <pgaikwad@nvidia.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
This commit is contained in:
Stephen Warren 2013-01-11 13:16:22 +05:30
parent 89572c77cd
commit 270f8ce312
2 changed files with 211 additions and 0 deletions

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NVIDIA Tegra20 Clock And Reset Controller
This binding uses the common clock binding:
Documentation/devicetree/bindings/clock/clock-bindings.txt
The CAR (Clock And Reset) Controller on Tegra is the HW module responsible
for muxing and gating Tegra's clocks, and setting their rates.
Required properties :
- compatible : Should be "nvidia,tegra20-car"
- reg : Should contain CAR registers location and length
- clocks : Should contain phandle and clock specifiers for two clocks:
the 32 KHz "32k_in", and the board-specific oscillator "osc".
- #clock-cells : Should be 1.
In clock consumers, this cell represents the clock ID exposed by the CAR.
The first 96 clocks are numbered to match the bits in the CAR's CLK_OUT_ENB
registers. These IDs often match those in the CAR's RST_DEVICES registers,
but not in all cases. Some bits in CLK_OUT_ENB affect multiple clocks. In
this case, those clocks are assigned IDs above 95 in order to highlight
this issue. Implementations that interpret these clock IDs as bit values
within the CLK_OUT_ENB or RST_DEVICES registers should be careful to
explicitly handle these special cases.
The balance of the clocks controlled by the CAR are assigned IDs of 96 and
above.
0 cpu
1 unassigned
2 unassigned
3 ac97
4 rtc
5 tmr
6 uart1
7 unassigned (register bit affects uart2 and vfir)
8 gpio
9 sdmmc2
10 unassigned (register bit affects spdif_in and spdif_out)
11 i2s1
12 i2c1
13 ndflash
14 sdmmc1
15 sdmmc4
16 twc
17 pwm
18 i2s2
19 epp
20 unassigned (register bit affects vi and vi_sensor)
21 2d
22 usbd
23 isp
24 3d
25 ide
26 disp2
27 disp1
28 host1x
29 vcp
30 unassigned
31 cache2
32 mem
33 ahbdma
34 apbdma
35 unassigned
36 kbc
37 stat_mon
38 pmc
39 fuse
40 kfuse
41 sbc1
42 snor
43 spi1
44 sbc2
45 xio
46 sbc3
47 dvc
48 dsi
49 unassigned (register bit affects tvo and cve)
50 mipi
51 hdmi
52 csi
53 tvdac
54 i2c2
55 uart3
56 unassigned
57 emc
58 usb2
59 usb3
60 mpe
61 vde
62 bsea
63 bsev
64 speedo
65 uart4
66 uart5
67 i2c3
68 sbc4
69 sdmmc3
70 pcie
71 owr
72 afi
73 csite
74 unassigned
75 avpucq
76 la
77 unassigned
78 unassigned
79 unassigned
80 unassigned
81 unassigned
82 unassigned
83 unassigned
84 irama
85 iramb
86 iramc
87 iramd
88 cram2
89 audio_2x a/k/a audio_2x_sync_clk
90 clk_d
91 unassigned
92 sus
93 cdev1
94 cdev2
95 unassigned
96 uart2
97 vfir
98 spdif_in
99 spdif_out
100 vi
101 vi_sensor
102 tvo
103 cve
104 osc
105 clk_32k a/k/a clk_s
106 clk_m
107 sclk
108 cclk
109 hclk
110 pclk
111 blink
112 pll_a
113 pll_a_out0
114 pll_c
115 pll_c_out1
116 pll_d
117 pll_d_out0
118 pll_e
119 pll_m
120 pll_m_out1
121 pll_p
122 pll_p_out1
123 pll_p_out2
124 pll_p_out3
125 pll_p_out4
126 pll_s
127 pll_u
128 pll_x
129 cop a/k/a avp
130 audio a/k/a audio_sync_clk
131 pll_ref
132 twd
Example SoC include file:
/ {
tegra_car: clock {
compatible = "nvidia,tegra20-car";
reg = <0x60006000 0x1000>;
#clock-cells = <1>;
};
usb@c5004000 {
clocks = <&tegra_car 58>; /* usb2 */
};
};
Example board file:
/ {
clocks {
compatible = "simple-bus";
#address-cells = <1>;
#size-cells = <0>;
osc: clock@0 {
compatible = "fixed-clock";
reg = <0>;
#clock-cells = <0>;
clock-frequency = <12000000>;
};
clk_32k: clock@1 {
compatible = "fixed-clock";
reg = <1>;
#clock-cells = <0>;
clock-frequency = <32768>;
};
};
&tegra_car {
clocks = <&clk_32k> <&osc>;
};
};

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0 42 0x04>;
};
tegra_car: clock {
compatible = "nvidia,tegra20-car";
reg = <0x60006000 0x1000>;
#clock-cells = <1>;
};
apbdma: dma {
compatible = "nvidia,tegra20-apbdma";
reg = <0x6000a000 0x1200>;