[PATCH v2 09/17] tegra: usb: fdt: Add additional device tree definitions for USB ports

Simon Glass sjg at chromium.org
Sat Dec 3 13:11:32 EST 2011


This adds peripheral IDs and timing information to the USB part of the
device tree for U-Boot.

The peripheral IDs provide easy access to clock registers. We will likely
remove this in favor of a full clock tree when it is available in the
kernel (but probably still retain the peripheral ID, just move it into
a clock node).

The USB timing information does apparently vary between boards sometimes,
so is include in the fdt for convenience.

Signed-off-by: Simon Glass <sjg at chromium.org>
---
Changes in v2:
- Change fdt property usbparmas to usbtiming
- Add details for port USB2

 arch/arm/dts/tegra20.dtsi |   69 +++++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 69 insertions(+), 0 deletions(-)

diff --git a/arch/arm/dts/tegra20.dtsi b/arch/arm/dts/tegra20.dtsi
index 6146d24..d7ab843 100644
--- a/arch/arm/dts/tegra20.dtsi
+++ b/arch/arm/dts/tegra20.dtsi
@@ -144,11 +144,78 @@
 		interrupts = < 63 >;
 	};
 
+/* This table has USB timing parameters for each Oscillator frequency we
+ * support. There are four sets of values:
+ *
+ * 1. PLLU configuration information (reference clock is osc/clk_m and
+ * PLLU-FOs are fixed at 12MHz/60MHz/480MHz).
+ *
+ *  Reference frequency     13.0MHz      19.2MHz      12.0MHz      26.0MHz
+ *  ----------------------------------------------------------------------
+ *      DIVN                960 (0x3c0)  200 (0c8)    960 (3c0h)   960 (3c0)
+ *      DIVM                13 (0d)      4 (04)       12 (0c)      26 (1a)
+ * Filter frequency (MHz)   1            4.8          6            2
+ * CPCON                    1100b        0011b        1100b        1100b
+ * LFCON0                   0            0            0            0
+ *
+ * 2. PLL CONFIGURATION & PARAMETERS for different clock generators:
+ *
+ * Reference frequency     13.0MHz         19.2MHz         12.0MHz     26.0MHz
+ * ---------------------------------------------------------------------------
+ * PLLU_ENABLE_DLY_COUNT   02 (0x02)       03 (03)         02 (02)     04 (04)
+ * PLLU_STABLE_COUNT       51 (33)         75 (4B)         47 (2F)    102 (66)
+ * PLL_ACTIVE_DLY_COUNT    05 (05)         06 (06)         04 (04)     09 (09)
+ * XTAL_FREQ_COUNT        127 (7F)        187 (BB)        118 (76)    254 (FE)
+ *
+ * 3. Debounce values IdDig, Avalid, Bvalid, VbusValid, VbusWakeUp, and
+ * SessEnd. Each of these signals have their own debouncer and for each of
+ * those one out of two debouncing times can be chosen (BIAS_DEBOUNCE_A or
+ * BIAS_DEBOUNCE_B).
+ *
+ * The values of DEBOUNCE_A and DEBOUNCE_B are calculated as follows:
+ *    0xffff -> No debouncing at all
+ *    <n> ms = <n> *1000 / (1/19.2MHz) / 4
+ *
+ * So to program a 1 ms debounce for BIAS_DEBOUNCE_A, we have:
+ * BIAS_DEBOUNCE_A[15:0] = 1000 * 19.2 / 4  = 4800 = 0x12c0
+ *
+ * We need to use only DebounceA for BOOTROM. We don't need the DebounceB
+ * values, so we can keep those to default.
+ *
+ * a4. The 20 microsecond delay after bias cell operation.
+ *  Reference frequency     13.0MHz      19.2MHz      12.0MHz      26.0MHz
+ */
+	usbtiming at 0 {
+		compatible = "nvidia,tegra20-usbtiming";
+		osc-frequency = <13000000>;
+		/* DivN, DivM, DivP, CPCON, LFCON, Delays     Debounce, Bias */
+		timing = <0x3c0 0x0d 0x00 0xc 0  0x02 0x33 0x05 0x7f 0x7ef4 5>;
+	};
+
+	usbtiming at 1 {
+		compatible = "nvidia,tegra20-usbtiming";
+		osc-frequency = <19200000>;
+		timing = <0x0c8 0x04 0x00 0x3 0  0x03 0x4b 0x06 0xbb 0xbb80 7>;
+	};
+
+	usbtiming at 2 {
+		compatible = "nvidia,tegra20-usbtiming";
+		osc-frequency = <12000000>;
+		timing = <0x3c0 0x0c 0x00 0xc 0  0x02 0x2f 0x04 0x76 0x7530 5>;
+	};
+
+	usbtiming at 3 {
+		compatible = "nvidia,tegra20-usbtiming";
+		osc-frequency = <26000000>;
+		timing = <0x3c0 0x1a 0x00 0xc 0  0x04 0x66 0x09 0xfe 0xfde8 9>;
+	};
+
 	usb at c5000000 {
 		compatible = "nvidia,tegra20-ehci", "usb-ehci";
 		reg = <0xc5000000 0x4000>;
 		interrupts = < 52 >;
 		phy_type = "utmi";
+		periph-id = <22>;	// PERIPH_ID_USBD
 	};
 
 	usb at c5004000 {
@@ -156,6 +223,7 @@
 		reg = <0xc5004000 0x4000>;
 		interrupts = < 53 >;
 		phy_type = "ulpi";
+		periph-id = <58>;	// PERIPH_ID_USB2
 	};
 
 	usb at c5008000 {
@@ -163,6 +231,7 @@
 		reg = <0xc5008000 0x4000>;
 		interrupts = < 129 >;
 		phy_type = "utmi";
+		periph-id = <59>;	// PERIPH_ID_USB3
 	};
 
 };
-- 
1.7.3.1



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