Commit d236843a authored by Matthew Rosato's avatar Matthew Rosato Committed by Joerg Roedel
Browse files

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: default avatarMatthew Rosato <mjrosato@linux.ibm.com>
Reviewed-by: default avatarNiklas Schnelle <schnelle@linux.ibm.com>
Tested-by: default avatarNiklas Schnelle <schnelle@linux.ibm.com>
Link: https://lore.kernel.org/r/20250212213418.182902-3-mjrosato@linux.ibm.com


Signed-off-by: default avatarJoerg Roedel <jroedel@suse.de>
parent 6d52cb73

arch/s390/pci/pci_bus.c

+25 −0
Original line number Diff line number Diff line
@@ -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.