[PATCH v10 26/26] sfc: support pio mapping based on cxl

[<alucerop@amd.com>]

From: Alejandro Lucero <alucerop@amd.com>

With a device supporting CXL and successfully initialised, use the cxl
region to map the memory range and use this mapping for PIO buffers.

Signed-off-by: Alejandro Lucero <alucerop@amd.com>
Acked-by: Edward Cree <ecree.xilinx@gmail.com>
---
 drivers/net/ethernet/sfc/ef10.c       | 50 +++++++++++++++++++++++----
 drivers/net/ethernet/sfc/efx_cxl.c    | 20 ++++++++++-
 drivers/net/ethernet/sfc/net_driver.h |  2 ++
 drivers/net/ethernet/sfc/nic.h        |  3 ++
 4 files changed, 67 insertions(+), 8 deletions(-)

diff --git a/drivers/net/ethernet/sfc/ef10.c b/drivers/net/ethernet/sfc/ef10.c
index 452009ed7a43..ce323af3586e 100644
--- a/drivers/net/ethernet/sfc/ef10.c
+++ b/drivers/net/ethernet/sfc/ef10.c
@@ -24,6 +24,7 @@
 #include <linux/wait.h>
 #include <linux/workqueue.h>
 #include <net/udp_tunnel.h>
+#include "efx_cxl.h"
 
 /* Hardware control for EF10 architecture including 'Huntington'. */
 
@@ -106,7 +107,7 @@ static int efx_ef10_get_vf_index(struct efx_nic *efx)
 
 static int efx_ef10_init_datapath_caps(struct efx_nic *efx)
 {
-	MCDI_DECLARE_BUF(outbuf, MC_CMD_GET_CAPABILITIES_V4_OUT_LEN);
+	MCDI_DECLARE_BUF(outbuf, MC_CMD_GET_CAPABILITIES_V7_OUT_LEN);
 	struct efx_ef10_nic_data *nic_data = efx->nic_data;
 	size_t outlen;
 	int rc;
@@ -177,6 +178,12 @@ static int efx_ef10_init_datapath_caps(struct efx_nic *efx)
 			  efx->num_mac_stats);
 	}
 
+	if (outlen < MC_CMD_GET_CAPABILITIES_V7_OUT_LEN)
+		nic_data->datapath_caps3 = 0;
+	else
+		nic_data->datapath_caps3 = MCDI_DWORD(outbuf,
+						      GET_CAPABILITIES_V7_OUT_FLAGS3);
+
 	return 0;
 }
 
@@ -919,6 +926,9 @@ static void efx_ef10_forget_old_piobufs(struct efx_nic *efx)
 static void efx_ef10_remove(struct efx_nic *efx)
 {
 	struct efx_ef10_nic_data *nic_data = efx->nic_data;
+#ifdef CONFIG_SFC_CXL
+	struct efx_probe_data *probe_data;
+#endif
 	int rc;
 
 #ifdef CONFIG_SFC_SRIOV
@@ -949,7 +959,12 @@ static void efx_ef10_remove(struct efx_nic *efx)
 
 	efx_mcdi_rx_free_indir_table(efx);
 
+#ifdef CONFIG_SFC_CXL
+	probe_data = container_of(efx, struct efx_probe_data, efx);
+	if (nic_data->wc_membase && !probe_data->cxl_pio_in_use)
+#else
 	if (nic_data->wc_membase)
+#endif
 		iounmap(nic_data->wc_membase);
 
 	rc = efx_mcdi_free_vis(efx);
@@ -1140,6 +1155,9 @@ static int efx_ef10_dimension_resources(struct efx_nic *efx)
 	unsigned int channel_vis, pio_write_vi_base, max_vis;
 	struct efx_ef10_nic_data *nic_data = efx->nic_data;
 	unsigned int uc_mem_map_size, wc_mem_map_size;
+#ifdef CONFIG_SFC_CXL
+	struct efx_probe_data *probe_data;
+#endif
 	void __iomem *membase;
 	int rc;
 
@@ -1263,8 +1281,25 @@ static int efx_ef10_dimension_resources(struct efx_nic *efx)
 	iounmap(efx->membase);
 	efx->membase = membase;
 
-	/* Set up the WC mapping if needed */
-	if (wc_mem_map_size) {
+	if (!wc_mem_map_size)
+		goto skip_pio;
+
+	/* Set up the WC mapping */
+
+#ifdef CONFIG_SFC_CXL
+	probe_data = container_of(efx, struct efx_probe_data, efx);
+	if ((nic_data->datapath_caps3 &
+	    (1 << MC_CMD_GET_CAPABILITIES_V7_OUT_CXL_CONFIG_ENABLE_LBN)) &&
+	    probe_data->cxl_pio_initialised) {
+		/* Using PIO through CXL mapping? */
+		nic_data->pio_write_base = probe_data->cxl->ctpio_cxl +
+					   (pio_write_vi_base * efx->vi_stride +
+					    ER_DZ_TX_PIOBUF - uc_mem_map_size);
+		probe_data->cxl_pio_in_use = true;
+	} else
+#endif
+	{
+		/* Using legacy PIO BAR mapping */
 		nic_data->wc_membase = ioremap_wc(efx->membase_phys +
 						  uc_mem_map_size,
 						  wc_mem_map_size);
@@ -1279,12 +1314,13 @@ static int efx_ef10_dimension_resources(struct efx_nic *efx)
 			nic_data->wc_membase +
 			(pio_write_vi_base * efx->vi_stride + ER_DZ_TX_PIOBUF -
 			 uc_mem_map_size);
-
-		rc = efx_ef10_link_piobufs(efx);
-		if (rc)
-			efx_ef10_free_piobufs(efx);
 	}
 
+	rc = efx_ef10_link_piobufs(efx);
+	if (rc)
+		efx_ef10_free_piobufs(efx);
+
+skip_pio:
 	netif_dbg(efx, probe, efx->net_dev,
 		  "memory BAR at %pa (virtual %p+%x UC, %p+%x WC)\n",
 		  &efx->membase_phys, efx->membase, uc_mem_map_size,
diff --git a/drivers/net/ethernet/sfc/efx_cxl.c b/drivers/net/ethernet/sfc/efx_cxl.c
index eac849b4e0aa..76991da1d2a9 100644
--- a/drivers/net/ethernet/sfc/efx_cxl.c
+++ b/drivers/net/ethernet/sfc/efx_cxl.c
@@ -27,6 +27,7 @@ int efx_cxl_init(struct efx_probe_data *probe_data)
 	DECLARE_BITMAP(found, CXL_MAX_CAPS);
 	resource_size_t max_size;
 	struct mds_info sfc_mds_info;
+	struct range range;
 	struct efx_cxl *cxl;
 
 	u16 dvsec;
@@ -136,12 +137,28 @@ int efx_cxl_init(struct efx_probe_data *probe_data)
 		goto err_region;
 	}
 
+	rc = cxl_get_region_range(cxl->efx_region, &range);
+	if (rc) {
+		pci_err(pci_dev, "CXL getting regions params failed");
+		goto err_region_params;
+	}
+
+	cxl->ctpio_cxl = ioremap(range.start, range.end - range.start + 1);
+	if (!cxl->ctpio_cxl) {
+		pci_err(pci_dev, "CXL ioremap region (%pra) pfailed", &range);
+		rc = -ENOMEM;
+		goto err_region_params;
+	}
+
 	probe_data->cxl = cxl;
+	probe_data->cxl_pio_initialised = true;
 
 	return 0;
 
+err_region_params:
+	cxl_accel_region_detach(cxl->cxled);
 err_region:
-	cxl_dpa_free(probe_data->cxl->cxled);
+	cxl_dpa_free(cxl->cxled);
 err_regs:
 	kfree(probe_data->cxl);
 	return rc;
@@ -151,6 +168,7 @@ int efx_cxl_init(struct efx_probe_data *probe_data)
 void efx_cxl_exit(struct efx_probe_data *probe_data)
 {
 	if (probe_data->cxl) {
+		iounmap(probe_data->cxl->ctpio_cxl);
 		cxl_accel_region_detach(probe_data->cxl->cxled);
 		cxl_dpa_free(probe_data->cxl->cxled);
 		cxl_put_root_decoder(probe_data->cxl->cxlrd);
diff --git a/drivers/net/ethernet/sfc/net_driver.h b/drivers/net/ethernet/sfc/net_driver.h
index a2626bcd6a41..86cf49a922cb 100644
--- a/drivers/net/ethernet/sfc/net_driver.h
+++ b/drivers/net/ethernet/sfc/net_driver.h
@@ -1211,6 +1211,7 @@ struct efx_cxl;
  * @efx: Efx NIC details
  * @cxl: details of related cxl objects
  * @cxl_pio_initialised: cxl initialization outcome.
+ * @cxl_pio_in_use: PIO using CXL mapping
  */
 struct efx_probe_data {
 	struct pci_dev *pci_dev;
@@ -1218,6 +1219,7 @@ struct efx_probe_data {
 #ifdef CONFIG_SFC_CXL
 	struct efx_cxl *cxl;
 	bool cxl_pio_initialised;
+	bool cxl_pio_in_use;
 #endif
 };
 
diff --git a/drivers/net/ethernet/sfc/nic.h b/drivers/net/ethernet/sfc/nic.h
index 9fa5c4c713ab..c87cc9214690 100644
--- a/drivers/net/ethernet/sfc/nic.h
+++ b/drivers/net/ethernet/sfc/nic.h
@@ -152,6 +152,8 @@ enum {
  *	%MC_CMD_GET_CAPABILITIES response)
  * @datapath_caps2: Further Capabilities of datapath firmware (FLAGS2 field of
  * %MC_CMD_GET_CAPABILITIES response)
+ * @datapath_caps3: Further Capabilities of datapath firmware (FLAGS3 field of
+ * %MC_CMD_GET_CAPABILITIES response)
  * @rx_dpcpu_fw_id: Firmware ID of the RxDPCPU
  * @tx_dpcpu_fw_id: Firmware ID of the TxDPCPU
  * @must_probe_vswitching: Flag: vswitching has yet to be setup after MC reboot
@@ -186,6 +188,7 @@ struct efx_ef10_nic_data {
 	bool must_check_datapath_caps;
 	u32 datapath_caps;
 	u32 datapath_caps2;
+	u32 datapath_caps3;
 	unsigned int rx_dpcpu_fw_id;
 	unsigned int tx_dpcpu_fw_id;
 	bool must_probe_vswitching;
-- 
2.17.1