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The current ATU setup only supports a single memory resource which
isn't sufficient if there are also prefetchable memory regions. In order
to support multiple memory regions, we need to move away from fixed ATU
slots and rework the assignment. As there's always an ATU entry for
config space, let's assign index 0 to config space. Then we assign
memory resources to index 1 and up. Finally, if we have an I/O region
and slots remaining, we assign the I/O region last. If there aren't
remaining slots, we keep the same config and I/O space sharing.
Cc: Vidya Sagar <vidyas@xxxxxxxxxx>
Cc: Jingoo Han <jingoohan1@xxxxxxxxx>
Cc: Gustavo Pimentel <gustavo.pimentel@xxxxxxxxxxxx>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx>
Cc: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
Signed-off-by: Rob Herring <robh@xxxxxxxxxx>
---
For 5.11. This is based on the regression fix for 5.10 I sent[1].
Rob
[1] https://lore.kernel.org/linux-pci/20201026154852.221483-1-robh@xxxxxxxxxx/
.../pci/controller/dwc/pcie-designware-host.c | 54 +++++++++++--------
drivers/pci/controller/dwc/pcie-designware.h | 6 +--
2 files changed, 34 insertions(+), 26 deletions(-)
diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
index 44c2a6572199..a6ffab9b537e 100644
--- a/drivers/pci/controller/dwc/pcie-designware-host.c
+++ b/drivers/pci/controller/dwc/pcie-designware-host.c
@@ -464,9 +464,7 @@ static void __iomem *dw_pcie_other_conf_map_bus(struct pci_bus *bus,
type = PCIE_ATU_TYPE_CFG1;
- dw_pcie_prog_outbound_atu(pci, PCIE_ATU_REGION_INDEX1,
- type, pp->cfg0_base,
- busdev, pp->cfg0_size);
+ dw_pcie_prog_outbound_atu(pci, 0, type, pp->cfg0_base, busdev, pp->cfg0_size);
return pp->va_cfg0_base + where;
}
@@ -480,9 +478,8 @@ static int dw_pcie_rd_other_conf(struct pci_bus *bus, unsigned int devfn,
ret = pci_generic_config_read(bus, devfn, where, size, val);
- if (!ret && pci->num_viewport <= 2)
- dw_pcie_prog_outbound_atu(pci, PCIE_ATU_REGION_INDEX1,
- PCIE_ATU_TYPE_IO, pp->io_base,
+ if (!ret && pci->io_cfg_atu_shared)
+ dw_pcie_prog_outbound_atu(pci, 0, PCIE_ATU_TYPE_IO, pp->io_base,
pp->io_bus_addr, pp->io_size);
return ret;
@@ -497,9 +494,8 @@ static int dw_pcie_wr_other_conf(struct pci_bus *bus, unsigned int devfn,
ret = pci_generic_config_write(bus, devfn, where, size, val);
- if (!ret && pci->num_viewport <= 2)
- dw_pcie_prog_outbound_atu(pci, PCIE_ATU_REGION_INDEX1,
- PCIE_ATU_TYPE_IO, pp->io_base,
+ if (!ret && pci->io_cfg_atu_shared)
+ dw_pcie_prog_outbound_atu(pci, 0, PCIE_ATU_TYPE_IO, pp->io_base,
pp->io_bus_addr, pp->io_size);
return ret;
@@ -586,21 +582,35 @@ void dw_pcie_setup_rc(struct pcie_port *pp)
* ATU, so we should not program the ATU here.
*/
if (pp->bridge->child_ops == &dw_child_pcie_ops) {
- struct resource_entry *tmp, *entry = NULL;
+ int atu_idx = 0;
+ struct resource_entry *entry;
/* Get last memory resource entry */
- resource_list_for_each_entry(tmp, &pp->bridge->windows)
- if (resource_type(tmp->res) == IORESOURCE_MEM)
- entry = tmp;
-
- dw_pcie_prog_outbound_atu(pci, PCIE_ATU_REGION_INDEX0,
- PCIE_ATU_TYPE_MEM, entry->res->start,
- entry->res->start - entry->offset,
- resource_size(entry->res));
- if (pci->num_viewport > 2)
- dw_pcie_prog_outbound_atu(pci, PCIE_ATU_REGION_INDEX2,
- PCIE_ATU_TYPE_IO, pp->io_base,
- pp->io_bus_addr, pp->io_size);
+ resource_list_for_each_entry(entry, &pp->bridge->windows) {
+ if (resource_type(entry->res) != IORESOURCE_MEM)
+ continue;
+
+ if (pci->num_viewport <= ++atu_idx)
+ break;
+
+ dw_pcie_prog_outbound_atu(pci, atu_idx,
+ PCIE_ATU_TYPE_MEM, entry->res->start,
+ entry->res->start - entry->offset,
+ resource_size(entry->res));
+ }
+
+ if (pp->io_size) {
+ if (pci->num_viewport > ++atu_idx)
+ dw_pcie_prog_outbound_atu(pci, atu_idx,
+ PCIE_ATU_TYPE_IO, pp->io_base,
+ pp->io_bus_addr, pp->io_size);
+ else
+ pci->io_cfg_atu_shared = true;
+ }
+
+ if (pci->num_viewport <= atu_idx)
+ dev_warn(pci->dev, "Resources exceed number of ATU entries (%d)",
+ pci->num_viewport);
}
dw_pcie_writel_dbi(pci, PCI_BASE_ADDRESS_0, 0);
diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h
index 9d2f511f13fa..ed19c34dd0fe 100644
--- a/drivers/pci/controller/dwc/pcie-designware.h
+++ b/drivers/pci/controller/dwc/pcie-designware.h
@@ -80,9 +80,6 @@
#define PCIE_ATU_VIEWPORT 0x900
#define PCIE_ATU_REGION_INBOUND BIT(31)
#define PCIE_ATU_REGION_OUTBOUND 0
-#define PCIE_ATU_REGION_INDEX2 0x2
-#define PCIE_ATU_REGION_INDEX1 0x1
-#define PCIE_ATU_REGION_INDEX0 0x0
#define PCIE_ATU_CR1 0x904
#define PCIE_ATU_TYPE_MEM 0x0
#define PCIE_ATU_TYPE_IO 0x2
@@ -266,7 +263,6 @@ struct dw_pcie {
/* Used when iatu_unroll_enabled is true */
void __iomem *atu_base;
u32 num_viewport;
- u8 iatu_unroll_enabled;
struct pcie_port pp;
struct dw_pcie_ep ep;
const struct dw_pcie_ops *ops;
@@ -274,6 +270,8 @@ struct dw_pcie {
int num_lanes;
int link_gen;
u8 n_fts[2];
+ bool iatu_unroll_enabled: 1;
+ bool io_cfg_atu_shared: 1;
};
#define to_dw_pcie_from_pp(port) container_of((port), struct dw_pcie, pp)
--
2.25.1
