Re: [PATCH 6/6] ARM: dts: Add pcie controller node for SamsungEXYNOS5440 SoC

From: Jingoo Han
Date: Wed Mar 27 2013 - 04:36:02 EST


On Tuesday, March 26, 2013 2:05 AM, Jason Gunthorpe wrote:
>
> On Sat, Mar 23, 2013 at 01:09:18PM +0900, Jingoo Han wrote:
>
> > + pcie0@40000000 {
> > + compatible = "samsung,exynos5440-pcie";
> > + reg = <0x40000000 0x4000
> > + 0x290000 0x1000
> > + 0x270000 0x1000
> > + 0x271000 0x40>;
> > + interrupts = <0 20 0>, <0 21 0>, <0 22 0>;
> > + #address-cells = <3>;
> > + #size-cells = <2>;
> > + device_type = "pci";
> > + bus-range = <0x0 0xf>;
> > + ranges = <0x00000800 0 0x40000000 0x40000000 0 0x00200000 /* configuration space */
> > + 0x81000000 0 0 0x40200000 0 0x00004000 /* downstream I/O */
> > + 0x82000000 0 0 0x40204000 0 0x10000000>; /* non-prefetchable memory */
> > + };
>
> Can you send the lspci output so these bindings can be properly
> reviewed? What PCI devices are internal to the SOC?
>
> What is behind 'exynos_pcie_wr_own_conf' ? Is this a root port bridge
> config space? What line is it in the lspci output? Can you include a
> lspci -vv for it as well?

Hi Jason Gunthorpe,
Thank you for your comment :)

Here is the lspci -vv output.
I tested Exynos PCIe with e1000e lan card.

00:00.0 PCI bridge: Samsung Electronics Co Ltd Device a549 (rev 01) (prog-if 00 [Normal decode])
Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr+ Stepping- SERR+ FastB2B- DisINTx-
Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
Latency: 0, Cache Line Size: 64 bytes
Bus: primary=00, secondary=01, subordinate=01, sec-latency=0
I/O behind bridge: 00000000-00000fff
Memory behind bridge: 40300000-403fffff
Prefetchable memory behind bridge: 40400000-404fffff
Secondary status: 66MHz- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- <SERR- <PERR-
BridgeCtl: Parity+ SERR- NoISA- VGA- MAbort- >Reset- FastB2B-
PriDiscTmr- SecDiscTmr- DiscTmrStat- DiscTmrSERREn-
Capabilities: <access denied>
Kernel driver in use: pcieport

01:00.0 Ethernet controller: Intel Corporation 82574L Gigabit Network Connection
Subsystem: Intel Corporation Gigabit CT Desktop Adapter
Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr+ Stepping- SERR+ FastB2B- DisINTx-
Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
Latency: 0, Cache Line Size: 64 bytes
Interrupt: pin A routed to IRQ 53
Region 0: Memory at 40380000 (32-bit, non-prefetchable) [size=128K]
Region 1: Memory at 40300000 (32-bit, non-prefetchable) [size=512K]
Region 2: I/O ports at 40200000 [disabled] [size=32]
Region 3: Memory at 403a0000 (32-bit, non-prefetchable) [size=16K]
[virtual] Expansion ROM at 40400000 [disabled] [size=256K]
Capabilities: <access denied>
Kernel driver in use: e1000e

10:00.0 PCI bridge: Samsung Electronics Co Ltd Device a549 (rev 01) (prog-if 00 [Normal decode])
Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr+ Stepping- SERR+ FastB2B- DisINTx-
Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
Latency: 0, Cache Line Size: 64 bytes
Bus: primary=10, secondary=11, subordinate=11, sec-latency=0
Secondary status: 66MHz- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- <SERR- <PERR-
BridgeCtl: Parity+ SERR- NoISA- VGA- MAbort- >Reset- FastB2B-
PriDiscTmr- SecDiscTmr- DiscTmrStat- DiscTmrSERREn-
Capabilities: <access denied>
Kernel driver in use: pcieport



>
> Your DT has overlapping bus-ranges, and two top level nodes. This is
> going to require separate PCI domains in Linux.
>
> However, based on your driver this HW looks similar to tegra, did you
> review how tegra is setup? Merging all the ports into a single domain
> is certainly preferred.

In Tegra case, the address of IO control register is same.
+ pcie-controller {
+ compatible = "nvidia,tegra20-pcie";
+ reg = <0x80003000 0x00000800 /* PADS registers */
+ 0x80003800 0x00000200 /* AFI registers */
+ 0x81000000 0x01000000 /* configuration space */
+ 0x90000000 0x10000000>; /* extended configuration space */

But, in Exynos case, address of IP control register is different
between PCIe0 and PCIe1.

+ pcie0@40000000 {
+ compatible = "samsung,exynos5440-pcie";
+ reg = <0x40000000 0x4000
+ 0x290000 0x1000
+ 0x270000 0x1000
+ 0x271000 0x40>;

+ pcie1@60000000 {
+ compatible = "samsung,exynos5440-pcie";
+ reg = <0x60000000 0x4000
+ 0x2a0000 0x1000
+ 0x272000 0x1000
+ 0x271040 0x40>;


>
> > + pcie1@60000000 {
> > + compatible = "samsung,exynos5440-pcie";
> > + reg = <0x60000000 0x4000
> > + 0x2a0000 0x1000
> > + 0x272000 0x1000
> > + 0x271040 0x40>;
> > + interrupts = <0 23 0>, <0 24 0>, <0 25 0>;
> > + #address-cells = <3>;
> > + #size-cells = <2>;
> > + device_type = "pci";
> > + bus-range = <0x0 0xf>;
> > + ranges = <0x00000800 0 0x60000000 0x60000000 0 0x00200000 /* configuration space */
>
> Do not include configuration space in ranges

How can I include configuration space?
Please let me know kindly :)

>
> > + 0x81000000 0 0 0x60200000 0 0x00004000 /* downstream I/O */
>
> Please confirm that an MMIO to 0x60200000 produces a PCI-E IO TLP to
> address 0
>
> > + 0x82000000 0 0 0x60204000 0 0x10000000>; /* non-prefetchable memory */
>
> Please check this, generally it should be:
>
> 0x82000000 0 0x60204000 0x60204000 0 0x10000000>; /* non-prefetchable memory */
>
> Reflecting an identity mapping for MMIO - eg MMIO access to 0x60204000
> producse a PCI Memory TLP to address 0x60204000 - unless your hardware
> is actually doing address translation (then there are other things to
> confirm..)

OK, I will change it.

>
> It is usual to have an interrupt-map - have you tested that interrupts
> resolve properly?

There is no problem about interrupts.
However, I will consider an interrupt-map.

>
> It looks like the INTx's should be routed by an interrupt-map to the
> pulse pin. Consider an interrupt controller to decode the INT ABCD.
>
> Regards,
> Jason

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