On Mon, Apr 21, 2025 at 11:43:58AM +0530, Aneesh Kumar K.V wrote:
> Dan Williams <dan.j.williams@xxxxxxxxx> writes:
>
> > There are two components to establishing an encrypted link, provisioning
> > the stream in Partner Port config-space, and programming the keys into
> > the link layer via IDE_KM (IDE Key Management). This new library,
> > drivers/pci/ide.c, enables the former. IDE_KM, via a TSM low-level
> > driver, is saved for later.
> >
> ....
>
> > +/**
> > + * pci_ide_stream_setup() - program settings to Selective IDE Stream registers
> > + * @pdev: PCIe device object for either a Root Port or Endpoint Partner Port
> > + * @ide: registered IDE settings descriptor
> > + *
> > + * When @pdev is a PCI_EXP_TYPE_ENDPOINT then the PCI_IDE_EP partner
> > + * settings are written to @pdev's Selective IDE Stream register block,
> > + * and when @pdev is a PCI_EXP_TYPE_ROOT_PORT, the PCI_IDE_RP settings
> > + * are selected.
> > + */
> > +void pci_ide_stream_setup(struct pci_dev *pdev, struct pci_ide *ide)
> > +{
> > + struct pci_ide_partner *settings = to_settings(pdev, ide);
> > + int pos;
> > + u32 val;
> > +
> > + if (!settings)
> > + return;
> > +
> > + pos = sel_ide_offset(pdev->nr_link_ide, settings->stream_index,
> > + pdev->nr_ide_mem);
> >
>
> This and the similar offset caclulation below needs the EXT_CAP_ID_IDE offset
>
> modified drivers/pci/ide.c
> @@ -10,11 +10,13 @@
> #include <linux/bitfield.h>
> #include "pci.h"
>
> -static int sel_ide_offset(int nr_link_ide, int stream_index, int nr_ide_mem)
> +static int sel_ide_offset(struct pci_dev *pdev, int nr_link_ide,
> + int stream_index, int nr_ide_mem)
> {
> int offset;
>
> - offset = PCI_IDE_LINK_STREAM_0 + nr_link_ide * PCI_IDE_LINK_BLOCK_SIZE;
> + offset = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_IDE);
> + offset += PCI_IDE_LINK_STREAM_0 + nr_link_ide * PCI_IDE_LINK_BLOCK_SIZE;
ide_cap, nr_link_ide, nr_ide_mem are all cached in pci_dev structure at
the end of pci_ide_init().
So either use all cached value in pdev (not for pci_ide_init()):
static int sel_ide_offset(struct pci_dev *pdev, int stream_index)
or don't use any cached value:
static int sel_ide_offset(u16 dev_cap, int nr_link_ide, int stream_index, int nr_ide_mem)
or keep sel_ide_offset() unchanged, alway do:
ide_cap + sel_ide_offset()
>
> /*
> * Assume a constant number of address association resources per
> @@ -66,7 +68,7 @@ void pci_ide_init(struct pci_dev *pdev)
> nr_streams = min(1 + FIELD_GET(PCI_IDE_CAP_SEL_NUM_MASK, val),
> CONFIG_PCI_IDE_STREAM_MAX);
> for (int i = 0; i < nr_streams; i++) {
> - int offset = sel_ide_offset(nr_link_ide, i, nr_ide_mem);
> + int offset = sel_ide_offset(pdev, nr_link_ide, i, nr_ide_mem);
> int nr_assoc;
> u32 val;
With your change, the next line will be broken:
- pci_read_config_dword(pdev, ide_cap + offset, &val);
+ pci_read_config_dword(pdev, offset, &val);
Thanks,
Yilun
