AnsweredAssumed Answered

About the change of i.MX6 PCIe RC and EP

Question asked by George Fukutomi on Apr 4, 2014
Latest reply on Apr 11, 2014 by George Fukutomi

Dear All,

 

We want to use PCIe on original OS.

The setting value is investigated by dump registers on Linux.

 

RM has the following descriptions about the switching of RC and EP.

 

Page 2052 in Applications Processor Reference Manual (Document Number: IMX6SDLRM Rev. 1, 04/2013) :

Section 37.4.13 GPR12 (IOMUXC_GPR12)

Address: 20E_0000h base + 30h offset = 20E_0030h

Field : 15-12  DEVICE_TYPE

Description :

PCIe_CTL - Device/Port Type. Indicates the specific type of

this PCI Express Function (EP or RC)

DEVICE_TYPE field values 0011-1111 are reserved.

          • 0000 PCIE_EP - EP Mode
          • 0010 PCIE_RC - RC Mode

 

However, the dump value was "0100"

 

root@wandboard:~# lspci

00:00.0 PCI bridge: Device 16c3:abcd (rev 01)

01:00.0 PCI bridge: Texas Instruments XIO2001 PCI Express-to-PCI Bridge

02:00.0 RAM memory: XXXXXXXXXXXXXXXXXXXXXXXXXXXXX. Device 8002 (rev 01)

 

root@wandboard:/# ./unit_tests/memtool 20E0030 10

E

Reading 0x10 count starting at address 0x020E0030

 

0x020E0030:  0F004490 0593A046 00000000 00000000

0x020E0040:  00000000 00000000 00000000 00000003

0x020E0050:  00000003 00000005 00000005 00000005

0x020E0060:  00000005 00000005 00000005 00000005

root@wandboard:~#

 

Please let me know what kind of meaning this value has.

 

Best Regard,

George

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