s390/pci: store DMA offset in bus_dma_region

PCI devices on s390 have a DMA offset that is reported via CLP.  In
preparation for allowing identity domains, setup the bus_dma_region
for all PCI devices using the reported CLP value.

Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
Tested-by: Niklas Schnelle <schnelle@linux.ibm.com>
Link: https://lore.kernel.org/r/20250212213418.182902-3-mjrosato@linux.ibm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This commit is contained in:
Matthew Rosato 2025-02-12 16:34:16 -05:00 committed by Joerg Roedel
parent 6d52cb738a
commit d236843a69

View file

@ -19,6 +19,7 @@
#include <linux/jump_label.h>
#include <linux/pci.h>
#include <linux/printk.h>
#include <linux/dma-direct.h>
#include <asm/pci_clp.h>
#include <asm/pci_dma.h>
@ -283,10 +284,34 @@ static struct zpci_bus *zpci_bus_alloc(int topo, bool topo_is_tid)
return zbus;
}
static void pci_dma_range_setup(struct pci_dev *pdev)
{
struct zpci_dev *zdev = to_zpci(pdev);
struct bus_dma_region *map;
u64 aligned_end;
map = kzalloc(sizeof(*map), GFP_KERNEL);
if (!map)
return;
map->cpu_start = 0;
map->dma_start = PAGE_ALIGN(zdev->start_dma);
aligned_end = PAGE_ALIGN_DOWN(zdev->end_dma + 1);
if (aligned_end >= map->dma_start)
map->size = aligned_end - map->dma_start;
else
map->size = 0;
WARN_ON_ONCE(map->size == 0);
pdev->dev.dma_range_map = map;
}
void pcibios_bus_add_device(struct pci_dev *pdev)
{
struct zpci_dev *zdev = to_zpci(pdev);
pci_dma_range_setup(pdev);
/*
* With pdev->no_vf_scan the common PCI probing code does not
* perform PF/VF linking.