Re: [PATCH 0/3] Add support to handle prefetchable memory

From: Vidya Sagar
Date: Wed Nov 04 2020 - 02:47:16 EST


Lorenzo / Bjorn,
Could you please review patches-1 & 2 in this series?
For the third patch, we already went with Rob's patch @ http://patchwork.ozlabs.org/project/linux-pci/patch/20201026154852.221483-1-robh@xxxxxxxxxx/

Thanks,
Vidya Sagar

On 10/26/2020 6:02 PM, Thierry Reding wrote:
On Sat, Oct 24, 2020 at 04:03:41AM +0000, Jingoo Han wrote:
On 10/23/20, 3:57 PM, Vidya Sagar wrote:

This patch series adds support for configuring the DesignWare IP's ATU
region for prefetchable memory translations.
It first starts by flagging a warning if the size of non-prefetchable
aperture goes beyond 32-bit as PCIe spec doesn't allow it.
And then adds required support for programming the ATU to handle higher
(i.e. >4GB) sizes and then finally adds support for differentiating
between prefetchable and non-prefetchable regions and configuring one of
the ATU regions for prefetchable memory translations purpose.

Vidya Sagar (3):
PCI: of: Warn if non-prefetchable memory aperture size is > 32-bit
PCI: dwc: Add support to program ATU for >4GB memory aperture sizes
PCI: dwc: Add support to handle prefetchable memory mapping

For 2nd & 3rd,
Acked-by: Jingoo <jingoohan1@xxxxxxxxx>
But, I still want someone to ack 1st patch, not me.

To Vidya,
If possible, can you ask your coworker to give 'Tested-by'? It will be very helpful.
Thank you.

On next-20201026 (but also going back quite a while) I'm seeing this
during boot on Jetson AGX Xavier (Tegra194):

[ 3.493382] ahci 0001:01:00.0: version 3.0
[ 3.493889] ahci 0001:01:00.0: SSS flag set, parallel bus scan disabled
[ 4.497706] ahci 0001:01:00.0: controller reset failed (0xffffffff)
[ 4.498114] ahci: probe of 0001:01:00.0 failed with error -5

After applying this series, AHCI over PCI is back to normal:

[ 3.543230] ahci 0001:01:00.0: AHCI 0001.0000 32 slots 1 ports 6 Gbps 0x1 impl SATA mode
[ 3.550841] ahci 0001:01:00.0: flags: 64bit ncq sntf led only pmp fbs pio slum part sxs
[ 3.559747] scsi host0: ahci
[ 3.561998] ata1: SATA max UDMA/133 abar m512@0x1230010000 port 0x1230010100 irq 63

So for the series:

Tested-by: Thierry Reding <treding@xxxxxxxxxx>