[dpdk-dev] [PATCH 4/4] cxgbe: configure PCIe extended tags

[Rahul Lakkireddy <rahul.lakkireddy@chelsio.com>]

Add support to configure minimum and maximum PCIe extended tag.

Signed-off-by: Rahul Lakkireddy <rahul.lakkireddy@chelsio.com>
Signed-off-by: Kumar Sanghvi <kumaras@chelsio.com>
---
 drivers/net/cxgbe/base/adapter.h |  1 +
 drivers/net/cxgbe/base/t4_regs.h | 20 ++++++++++++++++++++
 drivers/net/cxgbe/cxgbe_main.c   | 31 +++++++++++++++++++++++++++++++
 3 files changed, 52 insertions(+)

diff --git a/drivers/net/cxgbe/base/adapter.h b/drivers/net/cxgbe/base/adapter.h
index 58c6903..5e5f221 100644
--- a/drivers/net/cxgbe/base/adapter.h
+++ b/drivers/net/cxgbe/base/adapter.h
@@ -462,6 +462,7 @@ static inline void t4_write_reg64(struct adapter *adapter, u32 reg_addr,
 #define PCI_CAP_LIST_NEXT       1       /* Next capability in the list */
 #define PCI_EXP_DEVCTL          0x0008  /* Device control */
 #define PCI_EXP_DEVCTL2         40      /* Device Control 2 */
+#define PCI_EXP_DEVCTL_EXT_TAG  0x0100  /* Extended Tag Field Enable */
 #define PCI_EXP_DEVCTL_PAYLOAD  0x00E0  /* Max payload */
 #define PCI_CAP_ID_VPD          0x03    /* Vital Product Data */
 #define PCI_VPD_ADDR            2       /* Address to access (15 bits!) */
diff --git a/drivers/net/cxgbe/base/t4_regs.h b/drivers/net/cxgbe/base/t4_regs.h
index 289c7e4..1100e16 100644
--- a/drivers/net/cxgbe/base/t4_regs.h
+++ b/drivers/net/cxgbe/base/t4_regs.h
@@ -420,6 +420,26 @@
 #define A_PCIE_FW 0x30b8
 #define A_PCIE_FW_PF 0x30bc
 
+#define A_PCIE_CFG2 0x3018
+
+#define S_TOTMAXTAG    0
+#define M_TOTMAXTAG    0x3U
+#define V_TOTMAXTAG(x) ((x) << S_TOTMAXTAG)
+
+#define S_T6_TOTMAXTAG    0
+#define M_T6_TOTMAXTAG    0x7U
+#define V_T6_TOTMAXTAG(x) ((x) << S_T6_TOTMAXTAG)
+
+#define A_PCIE_CMD_CFG	0x5980
+
+#define S_MINTAG	0
+#define M_MINTAG	0xffU
+#define V_MINTAG(x)	((x) << S_MINTAG)
+
+#define S_T6_MINTAG	0
+#define M_T6_MINTAG	0xffU
+#define V_T6_MINTAG(x)	((x) << S_T6_MINTAG)
+
 /* registers for module CIM */
 #define CIM_BASE_ADDR 0x7b00
 
diff --git a/drivers/net/cxgbe/cxgbe_main.c b/drivers/net/cxgbe/cxgbe_main.c
index 4d95f5d..ac5b48f 100644
--- a/drivers/net/cxgbe/cxgbe_main.c
+++ b/drivers/net/cxgbe/cxgbe_main.c
@@ -414,6 +414,36 @@ static void print_port_info(struct adapter *adap)
 	}
 }
 
+static void configure_pcie_ext_tag(struct adapter *adapter)
+{
+	u16 v;
+	int pos = t4_os_find_pci_capability(adapter, PCI_CAP_ID_EXP);
+
+	if (!pos)
+		return;
+
+	if (pos > 0) {
+		t4_os_pci_read_cfg2(adapter, pos + PCI_EXP_DEVCTL, &v);
+		v |= PCI_EXP_DEVCTL_EXT_TAG;
+		t4_os_pci_write_cfg2(adapter, pos + PCI_EXP_DEVCTL, v);
+		if (is_t6(adapter->params.chip)) {
+			t4_set_reg_field(adapter, A_PCIE_CFG2,
+					 V_T6_TOTMAXTAG(M_T6_TOTMAXTAG),
+					 V_T6_TOTMAXTAG(7));
+			t4_set_reg_field(adapter, A_PCIE_CMD_CFG,
+					 V_T6_MINTAG(M_T6_MINTAG),
+					 V_T6_MINTAG(8));
+		} else {
+			t4_set_reg_field(adapter, A_PCIE_CFG2,
+					 V_TOTMAXTAG(M_TOTMAXTAG),
+					 V_TOTMAXTAG(3));
+			t4_set_reg_field(adapter, A_PCIE_CMD_CFG,
+					 V_MINTAG(M_MINTAG),
+					 V_MINTAG(8));
+		}
+	}
+}
+
 /*
  * Tweak configuration based on system architecture, etc.  Most of these have
  * defaults assigned to them by Firmware Configuration Files (if we're using
@@ -799,6 +829,7 @@ static int adap_init0(struct adapter *adap)
 	}
 	t4_init_sge_params(adap);
 	t4_init_tp_params(adap);
+	configure_pcie_ext_tag(adap);
 
 	adap->params.drv_memwin = MEMWIN_NIC;
 	adap->flags |= FW_OK;
-- 
2.5.3