Changes between Version 7 and Version 8 of newport/PCIe

Timestamp:

04/08/2019 10:10:19 PM (6 years ago)

Author:

Tim Harvey

Comment:

added details on how to manually assert/de-assert PERST# from PEM's and PEM mapping

newport/PCIe

@@ -48 +48 @@
 [=#perst]
 == PCIe Reset ==
-PCI Reset signals (PERST#) are routed to the Mini-PCIe slots.
+PCI Reset signals (PERST#) are routed to the Mini-PCIe slots. On the Newport boards each Mini-PCIe socket has its own dedicated PCI Reset (PERST#) signal. These signals are managed during PCI enumeration by the software drivers in the BDK (Boot firmware) and the Linux kernel.
 
-On the Newport boards each Mini-PCIe socket has its own dedicated PCI Reset (PERST#) signal.
+If you wish to manually assert these signals (which should never be done for an actual PCIe device as it would likely require re-enumeration but may be useful for a non-PCIe device in a miniPCIe socket like a modem) you can use the {{{RST_SOFT_PRST}}} register.
 
-**Note:** Activating these lines is yet to be implemented in software. 
+You can use the following script to assert PERST# for PEM0, PEM1, or PEM2 on a Newport board:
+{{{#!bash
+#/bin/sh
+PEM=$1
+
+[ "$PEM" -ge 0 -a "$PEM" -le 2 ] || {
+   echo "Error: $0 [0|1|2]"
+   exit 1
+}
+RST_SOFT_PRST=$((0x87e0060016c0 + $((1*8)) ))
+printf "PEM%d 0x%x\n" $PEM $RST_SOFT_PRST
+
+devmem2 $RST_SOFT_PRST b 1 # assert low
+sleep 1
+devmem2 $RST_SOFT_PRST b 0 # assert high
+}}}
+
+The following table shows the mapping of the three CN80XX PEM's to miniPCIe socket:
+||= Board =||= PEM =||= miniPCIe Socket =||= Notes =||
+|| GW610x  || PEM2  || J6 || Provides USB2 as well as PCIe, mSATA, or USB3 (see [wiki:newport/bootloader/#hwconfig hwconfig]) ||
+|| GW620x  || PEM0  || J6 || Provides USB2 as well as PCIe, mSATA, or USB3 (see [wiki:newport/bootloader/#hwconfig hwconfig]) ||
+||         || PEM2  || J8 || Provides USB2 and PCIe ||
+|| GW630x  || PEM0  || J9 || Provides USB2 and PCIe ||
+||         || PEM1  || J11 || Provides USB2 as well as PCIe or USB3 (see [wiki:newport/bootloader/#hwconfig hwconfig]) ||
+||         || PEM2  || J10 || Provides USB2 and PCIe or mSATA (see [wiki:newport/bootloader/#hwconfig hwconfig]) ||
+|| GW640x  || PEM0  || J9  || Provides USB2 and PCIe ||
+||         || PEM1  || J11 || Provides USB2 and PCIe ||
+||         || PEM2  || J10 || Provides USB2 and PCIe or mSATA (see [wiki:newport/bootloader/#hwconfig hwconfig]) ||
+||         || N/A   || J12 || Provides USB2 and USB3 (PERST# is floating and not driven - no way to reset) ||
+
+
 
 = Mini-PCIe Mechanical Specification =