PCI: endpoint: Add support to associate secondary EPC with EPF

In the case of standard endpoint functions, only one endpoint controller
(EPC) will be associated with an endpoint function (EPF). However for
providing NTB (non transparent bridge) functionality, two EPCs should be
associated with a single EPF.  Add support to associate secondary EPC with
EPF. This is in preparation for adding NTB endpoint function driver.

Link: https://lore.kernel.org/r/20210201195809.7342-7-kishon@ti.com
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

1 files changed, 41 insertions, 16 deletions

diff --git a/drivers/pci/endpoint/pci-epf-core.c b/drivers/pci/endpoint/pci-epf-core.c
index e44a317a2a2a..79329ec6373c 100644
--- a/drivers/pci/endpoint/pci-epf-core.c
+++ b/drivers/pci/endpoint/pci-epf-core.c
@@ -74,24 +74,37 @@ EXPORT_SYMBOL_GPL(pci_epf_bind);
  * @epf: the EPF device from whom to free the memory
  * @addr: the virtual address of the PCI EPF register space
  * @bar: the BAR number corresponding to the register space
+ * @type: Identifies if the allocated space is for primary EPC or secondary EPC
  *
  * Invoke to free the allocated PCI EPF register space.
  */
-void pci_epf_free_space(struct pci_epf *epf, void *addr, enum pci_barno bar)
+void pci_epf_free_space(struct pci_epf *epf, void *addr, enum pci_barno bar,
+			enum pci_epc_interface_type type)
 {
 	struct device *dev = epf->epc->dev.parent;
+	struct pci_epf_bar *epf_bar;
+	struct pci_epc *epc;
 
 	if (!addr)
 		return;
 
-	dma_free_coherent(dev, epf->bar[bar].size, addr,
-			  epf->bar[bar].phys_addr);
+	if (type == PRIMARY_INTERFACE) {
+		epc = epf->epc;
+		epf_bar = epf->bar;
+	} else {
+		epc = epf->sec_epc;
+		epf_bar = epf->sec_epc_bar;
+	}
+
+	dev = epc->dev.parent;
+	dma_free_coherent(dev, epf_bar[bar].size, addr,
+			  epf_bar[bar].phys_addr);
 
-	epf->bar[bar].phys_addr = 0;
-	epf->bar[bar].addr = NULL;
-	epf->bar[bar].size = 0;
-	epf->bar[bar].barno = 0;
-	epf->bar[bar].flags = 0;
+	epf_bar[bar].phys_addr = 0;
+	epf_bar[bar].addr = NULL;
+	epf_bar[bar].size = 0;
+	epf_bar[bar].barno = 0;
+	epf_bar[bar].flags = 0;
 }
 EXPORT_SYMBOL_GPL(pci_epf_free_space);
 
@@ -101,15 +114,18 @@ EXPORT_SYMBOL_GPL(pci_epf_free_space);
  * @size: the size of the memory that has to be allocated
  * @bar: the BAR number corresponding to the allocated register space
  * @align: alignment size for the allocation region
+ * @type: Identifies if the allocation is for primary EPC or secondary EPC
  *
  * Invoke to allocate memory for the PCI EPF register space.
  */
 void *pci_epf_alloc_space(struct pci_epf *epf, size_t size, enum pci_barno bar,
-			  size_t align)
+			  size_t align, enum pci_epc_interface_type type)
 {
-	void *space;
-	struct device *dev = epf->epc->dev.parent;
+	struct pci_epf_bar *epf_bar;
 	dma_addr_t phys_addr;
+	struct pci_epc *epc;
+	struct device *dev;
+	void *space;
 
 	if (size < 128)
 		size = 128;
@@ -119,17 +135,26 @@ void *pci_epf_alloc_space(struct pci_epf *epf, size_t size, enum pci_barno bar,
 	else
 		size = roundup_pow_of_two(size);
 
+	if (type == PRIMARY_INTERFACE) {
+		epc = epf->epc;
+		epf_bar = epf->bar;
+	} else {
+		epc = epf->sec_epc;
+		epf_bar = epf->sec_epc_bar;
+	}
+
+	dev = epc->dev.parent;
 	space = dma_alloc_coherent(dev, size, &phys_addr, GFP_KERNEL);
 	if (!space) {
 		dev_err(dev, "failed to allocate mem space\n");
 		return NULL;
 	}
 
-	epf->bar[bar].phys_addr = phys_addr;
-	epf->bar[bar].addr = space;
-	epf->bar[bar].size = size;
-	epf->bar[bar].barno = bar;
-	epf->bar[bar].flags |= upper_32_bits(size) ?
+	epf_bar[bar].phys_addr = phys_addr;
+	epf_bar[bar].addr = space;
+	epf_bar[bar].size = size;
+	epf_bar[bar].barno = bar;
+	epf_bar[bar].flags |= upper_32_bits(size) ?
 				PCI_BASE_ADDRESS_MEM_TYPE_64 :
 				PCI_BASE_ADDRESS_MEM_TYPE_32;