cxgb4: Add HMA support

HMA(Host Memory Access) maps a part of host memory for T6-SO memfree cards.

This commit does the following:
- Query FW to check if we have HMA support. If yes, the params will
  return HMA size configured in FW. We will dma map memory based
  on this size.
- Also contains changes to get HMA memory information via debugfs.

Signed-off-by: Arjun Vynipadath <[email protected]>
Signed-off-by: Santosh Rastapur <[email protected]>
Signed-off-by: Michael Werner <[email protected]>
Signed-off-by: Ganesh GR <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

Author: arjunvynipadath

drivers/net/ethernet/chelsio/cxgb4/cxgb4.h

@@ -831,6 +831,16 @@ struct vf_info {
 	u16 vlan;
 };
 
+enum {
+	HMA_DMA_MAPPED_FLAG = 1
+};
+
+struct hma_data {
+	unsigned char flags;
+	struct sg_table *sgt;
+	dma_addr_t *phy_addr;	/* physical address of the page */
+};
+
 struct mbox_list {
 	struct list_head list;
 };
@@ -946,6 +956,9 @@ struct adapter {
 
 	/* Ethtool Dump */
 	struct ethtool_dump eth_dump;
+
+	/* HMA */
+	struct hma_data hma;
 };
 
 /* Support for "sched-class" command to allow a TX Scheduling Class to be

drivers/net/ethernet/chelsio/cxgb4/cxgb4_debugfs.c

@@ -2617,7 +2617,7 @@ int mem_open(struct inode *inode, struct file *file)
 
 	file->private_data = inode->i_private;
 
-	mem = (uintptr_t)file->private_data & 0x3;
+	mem = (uintptr_t)file->private_data & 0x7;
 	adap = file->private_data - mem;
 
 	(void)t4_fwcache(adap, FW_PARAM_DEV_FWCACHE_FLUSH);
@@ -2630,7 +2630,7 @@ static ssize_t mem_read(struct file *file, char __user *buf, size_t count,
 {
 	loff_t pos = *ppos;
 	loff_t avail = file_inode(file)->i_size;
-	unsigned int mem = (uintptr_t)file->private_data & 3;
+	unsigned int mem = (uintptr_t)file->private_data & 0x7;
 	struct adapter *adap = file->private_data - mem;
 	__be32 *data;
 	int ret;
@@ -3042,6 +3042,12 @@ int t4_setup_debugfs(struct adapter *adap)
 			add_debugfs_mem(adap, "mc", MEM_MC,
 					EXT_MEM_SIZE_G(size));
 		}
+
+		if (i & HMA_MUX_F) {
+			size = t4_read_reg(adap, MA_EXT_MEMORY1_BAR_A);
+			add_debugfs_mem(adap, "hma", MEM_HMA,
+					EXT_MEM1_SIZE_G(size));
+		}
 	}
 
 	de = debugfs_create_file_size("flash", S_IRUSR, adap->debugfs_root, adap,

drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c

@@ -1736,10 +1736,11 @@ EXPORT_SYMBOL(cxgb4_sync_txq_pidx);
 
 int cxgb4_read_tpte(struct net_device *dev, u32 stag, __be32 *tpte)
 {
-	struct adapter *adap;
-	u32 offset, memtype, memaddr;
 	u32 edc0_size, edc1_size, mc0_size, mc1_size, size;
 	u32 edc0_end, edc1_end, mc0_end, mc1_end;
+	u32 offset, memtype, memaddr;
+	struct adapter *adap;
+	u32 hma_size = 0;
 	int ret;
 
 	adap = netdev2adap(dev);
@@ -1759,6 +1760,10 @@ int cxgb4_read_tpte(struct net_device *dev, u32 stag, __be32 *tpte)
 	size = t4_read_reg(adap, MA_EXT_MEMORY0_BAR_A);
 	mc0_size = EXT_MEM0_SIZE_G(size) << 20;
 
+	if (t4_read_reg(adap, MA_TARGET_MEM_ENABLE_A) & HMA_MUX_F) {
+		size = t4_read_reg(adap, MA_EXT_MEMORY1_BAR_A);
+		hma_size = EXT_MEM1_SIZE_G(size) << 20;
+	}
 	edc0_end = edc0_size;
 	edc1_end = edc0_end + edc1_size;
 	mc0_end = edc1_end + mc0_size;
@@ -1770,7 +1775,10 @@ int cxgb4_read_tpte(struct net_device *dev, u32 stag, __be32 *tpte)
 		memtype = MEM_EDC1;
 		memaddr = offset - edc0_end;
 	} else {
-		if (offset < mc0_end) {
+		if (hma_size && (offset < (edc1_end + hma_size))) {
+			memtype = MEM_HMA;
+			memaddr = offset - edc1_end;
+		} else if (offset < mc0_end) {
 			memtype = MEM_MC0;
 			memaddr = offset - edc1_end;
 		} else if (is_t5(adap->params.chip)) {
@@ -3301,6 +3309,206 @@ static void setup_memwin_rdma(struct adapter *adap)
 	}
 }
 
+/* HMA Definitions */
+
+/* The maximum number of address that can be send in a single FW cmd */
+#define HMA_MAX_ADDR_IN_CMD	5
+
+#define HMA_PAGE_SIZE		PAGE_SIZE
+
+#define HMA_MAX_NO_FW_ADDRESS	(16 << 10)  /* FW supports 16K addresses */
+
+#define HMA_PAGE_ORDER					\
+	((HMA_PAGE_SIZE < HMA_MAX_NO_FW_ADDRESS) ?	\
+	ilog2(HMA_MAX_NO_FW_ADDRESS / HMA_PAGE_SIZE) : 0)
+
+/* The minimum and maximum possible HMA sizes that can be specified in the FW
+ * configuration(in units of MB).
+ */
+#define HMA_MIN_TOTAL_SIZE	1
+#define HMA_MAX_TOTAL_SIZE				\
+	(((HMA_PAGE_SIZE << HMA_PAGE_ORDER) *		\
+	  HMA_MAX_NO_FW_ADDRESS) >> 20)
+
+static void adap_free_hma_mem(struct adapter *adapter)
+{
+	struct scatterlist *iter;
+	struct page *page;
+	int i;
+
+	if (!adapter->hma.sgt)
+		return;
+
+	if (adapter->hma.flags & HMA_DMA_MAPPED_FLAG) {
+		dma_unmap_sg(adapter->pdev_dev, adapter->hma.sgt->sgl,
+			     adapter->hma.sgt->nents, PCI_DMA_BIDIRECTIONAL);
+		adapter->hma.flags &= ~HMA_DMA_MAPPED_FLAG;
+	}
+
+	for_each_sg(adapter->hma.sgt->sgl, iter,
+		    adapter->hma.sgt->orig_nents, i) {
+		page = sg_page(iter);
+		if (page)
+			__free_pages(page, HMA_PAGE_ORDER);
+	}
+
+	kfree(adapter->hma.phy_addr);
+	sg_free_table(adapter->hma.sgt);
+	kfree(adapter->hma.sgt);
+	adapter->hma.sgt = NULL;
+}
+
+static int adap_config_hma(struct adapter *adapter)
+{
+	struct scatterlist *sgl, *iter;
+	struct sg_table *sgt;
+	struct page *newpage;
+	unsigned int i, j, k;
+	u32 param, hma_size;
+	unsigned int ncmds;
+	size_t page_size;
+	u32 page_order;
+	int node, ret;
+
+	/* HMA is supported only for T6+ cards.
+	 * Avoid initializing HMA in kdump kernels.
+	 */
+	if (is_kdump_kernel() ||
+	    CHELSIO_CHIP_VERSION(adapter->params.chip) < CHELSIO_T6)
+		return 0;
+
+	/* Get the HMA region size required by fw */
+	param = (FW_PARAMS_MNEM_V(FW_PARAMS_MNEM_DEV) |
+		 FW_PARAMS_PARAM_X_V(FW_PARAMS_PARAM_DEV_HMA_SIZE));
+	ret = t4_query_params(adapter, adapter->mbox, adapter->pf, 0,
+			      1, &param, &hma_size);
+	/* An error means card has its own memory or HMA is not supported by
+	 * the firmware. Return without any errors.
+	 */
+	if (ret || !hma_size)
+		return 0;
+
+	if (hma_size < HMA_MIN_TOTAL_SIZE ||
+	    hma_size > HMA_MAX_TOTAL_SIZE) {
+		dev_err(adapter->pdev_dev,
+			"HMA size %uMB beyond bounds(%u-%lu)MB\n",
+			hma_size, HMA_MIN_TOTAL_SIZE, HMA_MAX_TOTAL_SIZE);
+		return -EINVAL;
+	}
+
+	page_size = HMA_PAGE_SIZE;
+	page_order = HMA_PAGE_ORDER;
+	adapter->hma.sgt = kzalloc(sizeof(*adapter->hma.sgt), GFP_KERNEL);
+	if (unlikely(!adapter->hma.sgt)) {
+		dev_err(adapter->pdev_dev, "HMA SG table allocation failed\n");
+		return -ENOMEM;
+	}
+	sgt = adapter->hma.sgt;
+	/* FW returned value will be in MB's
+	 */
+	sgt->orig_nents = (hma_size << 20) / (page_size << page_order);
+	if (sg_alloc_table(sgt, sgt->orig_nents, GFP_KERNEL)) {
+		dev_err(adapter->pdev_dev, "HMA SGL allocation failed\n");
+		kfree(adapter->hma.sgt);
+		adapter->hma.sgt = NULL;
+		return -ENOMEM;
+	}
+
+	sgl = adapter->hma.sgt->sgl;
+	node = dev_to_node(adapter->pdev_dev);
+	for_each_sg(sgl, iter, sgt->orig_nents, i) {
+		newpage = alloc_pages_node(node, __GFP_NOWARN | GFP_KERNEL,
+					   page_order);
+		if (!newpage) {
+			dev_err(adapter->pdev_dev,
+				"Not enough memory for HMA page allocation\n");
+			ret = -ENOMEM;
+			goto free_hma;
+		}
+		sg_set_page(iter, newpage, page_size << page_order, 0);
+	}
+
+	sgt->nents = dma_map_sg(adapter->pdev_dev, sgl, sgt->orig_nents,
+				DMA_BIDIRECTIONAL);
+	if (!sgt->nents) {
+		dev_err(adapter->pdev_dev,
+			"Not enough memory for HMA DMA mapping");
+		ret = -ENOMEM;
+		goto free_hma;
+	}
+	adapter->hma.flags |= HMA_DMA_MAPPED_FLAG;
+
+	adapter->hma.phy_addr = kcalloc(sgt->nents, sizeof(dma_addr_t),
+					GFP_KERNEL);
+	if (unlikely(!adapter->hma.phy_addr))
+		goto free_hma;
+
+	for_each_sg(sgl, iter, sgt->nents, i) {
+		newpage = sg_page(iter);
+		adapter->hma.phy_addr[i] = sg_dma_address(iter);
+	}
+
+	ncmds = DIV_ROUND_UP(sgt->nents, HMA_MAX_ADDR_IN_CMD);
+	/* Pass on the addresses to firmware */
+	for (i = 0, k = 0; i < ncmds; i++, k += HMA_MAX_ADDR_IN_CMD) {
+		struct fw_hma_cmd hma_cmd;
+		u8 naddr = HMA_MAX_ADDR_IN_CMD;
+		u8 soc = 0, eoc = 0;
+		u8 hma_mode = 1; /* Presently we support only Page table mode */
+
+		soc = (i == 0) ? 1 : 0;
+		eoc = (i == ncmds - 1) ? 1 : 0;
+
+		/* For last cmd, set naddr corresponding to remaining
+		 * addresses
+		 */
+		if (i == ncmds - 1) {
+			naddr = sgt->nents % HMA_MAX_ADDR_IN_CMD;
+			naddr = naddr ? naddr : HMA_MAX_ADDR_IN_CMD;
+		}
+		memset(&hma_cmd, 0, sizeof(hma_cmd));
+		hma_cmd.op_pkd = htonl(FW_CMD_OP_V(FW_HMA_CMD) |
+				       FW_CMD_REQUEST_F | FW_CMD_WRITE_F);
+		hma_cmd.retval_len16 = htonl(FW_LEN16(hma_cmd));
+
+		hma_cmd.mode_to_pcie_params =
+			htonl(FW_HMA_CMD_MODE_V(hma_mode) |
+			      FW_HMA_CMD_SOC_V(soc) | FW_HMA_CMD_EOC_V(eoc));
+
+		/* HMA cmd size specified in MB's */
+		hma_cmd.naddr_size =
+			htonl(FW_HMA_CMD_SIZE_V(hma_size) |
+			      FW_HMA_CMD_NADDR_V(naddr));
+
+		/* Total Page size specified in units of 4K */
+		hma_cmd.addr_size_pkd =
+			htonl(FW_HMA_CMD_ADDR_SIZE_V
+				((page_size << page_order) >> 12));
+
+		/* Fill the 5 addresses */
+		for (j = 0; j < naddr; j++) {
+			hma_cmd.phy_address[j] =
+				cpu_to_be64(adapter->hma.phy_addr[j + k]);
+		}
+		ret = t4_wr_mbox(adapter, adapter->mbox, &hma_cmd,
+				 sizeof(hma_cmd), &hma_cmd);
+		if (ret) {
+			dev_err(adapter->pdev_dev,
+				"HMA FW command failed with err %d\n", ret);
+			goto free_hma;
+		}
+	}
+
+	if (!ret)
+		dev_info(adapter->pdev_dev,
+			 "Reserved %uMB host memory for HMA\n", hma_size);
+	return ret;
+
+free_hma:
+	adap_free_hma_mem(adapter);
+	return ret;
+}
+
 static int adap_init1(struct adapter *adap, struct fw_caps_config_cmd *c)
 {
 	u32 v;
@@ -3754,6 +3962,12 @@ static int adap_init0_config(struct adapter *adapter, int reset)
 	if (ret < 0)
 		goto bye;
 
+	/* We will proceed even if HMA init fails. */
+	ret = adap_config_hma(adapter);
+	if (ret)
+		dev_err(adapter->pdev_dev,
+			"HMA configuration failed with error %d\n", ret);
+
 	/*
 	 * And finally tell the firmware to initialize itself using the
 	 * parameters from the Configuration File.
@@ -3960,6 +4174,11 @@ static int adap_init0(struct adapter *adap)
 	 * effect. Otherwise, it's time to try initializing the adapter.
 	 */
 	if (state == DEV_STATE_INIT) {
+		ret = adap_config_hma(adap);
+		if (ret)
+			dev_err(adap->pdev_dev,
+				"HMA configuration failed with error %d\n",
+				ret);
 		dev_info(adap->pdev_dev, "Coming up as %s: "\
 			 "Adapter already initialized\n",
 			 adap->flags & MASTER_PF ? "MASTER" : "SLAVE");
@@ -4349,6 +4568,7 @@ static int adap_init0(struct adapter *adap)
 	 * happened to HW/FW, stop issuing commands.
 	 */
 bye:
+	adap_free_hma_mem(adap);
 	kfree(adap->sge.egr_map);
 	kfree(adap->sge.ingr_map);
 	kfree(adap->sge.starving_fl);
@@ -5576,6 +5796,8 @@ static void remove_one(struct pci_dev *pdev)
 			t4_uld_clean_up(adapter);
 		}
 
+		adap_free_hma_mem(adapter);
+
 		disable_interrupts(adapter);
 
 		for_each_port(adapter, i)

drivers/net/ethernet/chelsio/cxgb4/t4_hw.c

@@ -487,7 +487,7 @@ static int t4_edc_err_read(struct adapter *adap, int idx)
  * t4_memory_rw_init - Get memory window relative offset, base, and size.
  * @adap: the adapter
  * @win: PCI-E Memory Window to use
- * @mtype: memory type: MEM_EDC0, MEM_EDC1 or MEM_MC
+ * @mtype: memory type: MEM_EDC0, MEM_EDC1, MEM_HMA or MEM_MC
  * @mem_off: memory relative offset with respect to @mtype.
  * @mem_base: configured memory base address.
  * @mem_aperture: configured memory window aperture.