[RFC PATCH 14/21] PCI: cadence: Implement ->msi_map_irq() ops

From: Kishon Vijay Abraham I <kishon@ti.com>
To: Bjorn Helgaas <bhelgaas@google.com>,
	Jonathan Corbet <corbet@lwn.net>,
	Rob Herring <robh+dt@kernel.org>, Jon Mason <jdmason@kudzu.us>,
	Dave Jiang <dave.jiang@intel.com>,
	Allen Hubbe <allenbh@gmail.com>,
	Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>, <kishon@ti.com>,
	<linux-pci@vger.kernel.org>, <linux-doc@vger.kernel.org>,
	<linux-kernel@vger.kernel.org>, <devicetree@vger.kernel.org>,
	<linux-ntb@googlegroups.com>
Subject: [RFC PATCH 14/21] PCI: cadence: Implement ->msi_map_irq() ops
Date: Thu, 26 Sep 2019 16:59:26 +0530	[thread overview]
Message-ID: <20190926112933.8922-15-kishon@ti.com> (raw)
In-Reply-To: <20190926112933.8922-1-kishon@ti.com>

Implement ->msi_map_irq() ops in order to map physical address to
MSI address and return MSI data.

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
---
 drivers/pci/controller/pcie-cadence-ep.c | 59 ++++++++++++++++++++++++
 1 file changed, 59 insertions(+)

diff --git a/drivers/pci/controller/pcie-cadence-ep.c b/drivers/pci/controller/pcie-cadence-ep.c
index ff4b4b8eb017..5d41c892177f 100644
--- a/drivers/pci/controller/pcie-cadence-ep.c
+++ b/drivers/pci/controller/pcie-cadence-ep.c
@@ -517,6 +517,64 @@ static int cdns_pcie_ep_send_msi_irq(struct cdns_pcie_ep *ep, u8 fn, u8 vfn,
 	return 0;
 }
 
+static int cdns_pcie_ep_map_msi_irq(struct pci_epc *epc, u8 fn, u8 vfn,
+				    phys_addr_t addr, u8 interrupt_num,
+				    u32 entry_size, u32 *msi_data)
+{
+	u32 sriov_cap = CDNS_PCIE_EP_FUNC_SRIOV_CAP_OFFSET;
+	struct cdns_pcie_ep *ep = epc_get_drvdata(epc);
+	u32 cap = CDNS_PCIE_EP_FUNC_MSI_CAP_OFFSET;
+	struct cdns_pcie *pcie = &ep->pcie;
+	u16 flags, mme, data, data_mask;
+	u32 first_vf_offset, stride;
+	u8 msi_count;
+	u64 pci_addr;
+	int ret;
+	int i;
+
+	if (vfn > 0) {
+		first_vf_offset = cdns_pcie_ep_fn_readw(pcie, fn, sriov_cap +
+							PCI_SRIOV_VF_OFFSET);
+		stride = cdns_pcie_ep_fn_readw(pcie, fn, sriov_cap +
+					       PCI_SRIOV_VF_STRIDE);
+		fn = fn + first_vf_offset + ((vfn - 1) * stride);
+	}
+
+	/* Check whether the MSI feature has been enabled by the PCI host. */
+	flags = cdns_pcie_ep_fn_readw(pcie, fn, cap + PCI_MSI_FLAGS);
+	if (!(flags & PCI_MSI_FLAGS_ENABLE))
+		return -EINVAL;
+
+	/* Get the number of enabled MSIs */
+	mme = (flags & PCI_MSI_FLAGS_QSIZE) >> 4;
+	msi_count = 1 << mme;
+	if (!interrupt_num || interrupt_num > msi_count)
+		return -EINVAL;
+
+	/* Compute the data value to be written. */
+	data_mask = msi_count - 1;
+	data = cdns_pcie_ep_fn_readw(pcie, fn, cap + PCI_MSI_DATA_64);
+	data = data & ~data_mask;
+
+	/* Get the PCI address where to write the data into. */
+	pci_addr = cdns_pcie_ep_fn_readl(pcie, fn, cap + PCI_MSI_ADDRESS_HI);
+	pci_addr <<= 32;
+	pci_addr |= cdns_pcie_ep_fn_readl(pcie, fn, cap + PCI_MSI_ADDRESS_LO);
+	pci_addr &= GENMASK_ULL(63, 2);
+
+	for (i = 0; i < interrupt_num; i++) {
+		ret = cdns_pcie_ep_map_addr(epc, fn, vfn, addr, pci_addr,
+					    entry_size);
+		if (ret)
+			return ret;
+		addr = addr + entry_size;
+	}
+
+	*msi_data = data;
+
+	return 0;
+}
+
 static int cdns_pcie_ep_send_msix_irq(struct cdns_pcie_ep *ep, u8 fn, u8 vfn,
 				      u16 interrupt_num)
 {
@@ -678,6 +736,7 @@ static const struct pci_epc_ops cdns_pcie_epc_ops = {
 	.set_msix	= cdns_pcie_ep_set_msix,
 	.get_msix	= cdns_pcie_ep_get_msix,
 	.raise_irq	= cdns_pcie_ep_raise_irq,
+	.map_msi_irq	= cdns_pcie_ep_map_msi_irq,
 	.start		= cdns_pcie_ep_start,
 	.get_features	= cdns_pcie_ep_get_features,
 };
-- 
2.17.1

