ath10k: configure frag desc memory to target for qca99X0

Pre qca99X0 chipsets follows the model where dynamically allocate
memory for frag desc on getting new skb for TX. But, this is not
going to be the case in qca99X0. It expects frag desc memory to be
allocated at boot time and let the driver to reuse allocated memory
after every TX completion. So there won't be any dynamic frag memory
memory allocation in qca99X0 during data transmission.

qca99X0 hardware doesn't need fragment desc address to be programmed
in msdu descriptor for every data transaction. It needs to know only
starting address of fragment descriptor at the time of the boot.
During data transmission, qca99X0 hardware can retrieve corresponding
frag addr by adding programmed frag desc base addr + msdu id.

Allocate continuous fragment descriptor memory (same size as number of
descriptor) at the time of target initialization and configure allocated
dma address to the target via HTT_H2T_MSG_TYPE_FRAG_DESC_BANK_CFG.

How this is allocated continuous memory is going to be used is not
covered in this patch. It just allocates memory and hand over to firmware.
If we don't do it at init time, qca99X0 will stall when firmware tries
to do TX.

Signed-off-by: Raja Mani <rmani@qti.qualcomm.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>

drivers/net/wireless/ath/ath10k/core.c

@@ -111,6 +111,7 @@ static const struct ath10k_hw_params ath10k_hw_params_list[] = {
 		.patch_load_addr = QCA99X0_HW_2_0_PATCH_LOAD_ADDR,
 		.uart_pin = 7,
 		.otp_exe_param = 0x00000700,
+		.continuous_frag_desc = true,
 		.fw = {
 			.dir = QCA99X0_HW_2_0_FW_DIR,
 			.fw = QCA99X0_HW_2_0_FW_FILE,

drivers/net/wireless/ath/ath10k/core.h

@@ -582,6 +582,12 @@ struct ath10k {
 		 */
 		bool has_shifted_cc_wraparound;
 
+		/* Some of chip expects fragment descriptor to be continuous
+		 * memory for any TX operation. Set continuous_frag_desc flag
+		 * for the hardware which have such requirement.
+		 */
+		bool continuous_frag_desc;
+
 		struct ath10k_hw_params_fw {
 			const char *dir;
 			const char *fw;

drivers/net/wireless/ath/ath10k/htt.c

@@ -249,5 +249,9 @@ int ath10k_htt_setup(struct ath10k_htt *htt)
 	if (status)
 		return status;
 
+	status = ath10k_htt_send_frag_desc_bank_cfg(htt);
+	if (status)
+		return status;
+
 	return ath10k_htt_send_rx_ring_cfg_ll(htt);
 }

drivers/net/wireless/ath/ath10k/htt.h

@@ -87,6 +87,11 @@ struct htt_data_tx_desc_frag {
 	__le32 len;
 } __packed;
 
+struct htt_msdu_ext_desc {
+	__le32 tso_flag[4];
+	struct htt_data_tx_desc_frag frags[6];
+};
+
 enum htt_data_tx_desc_flags0 {
 	HTT_DATA_TX_DESC_FLAGS0_MAC_HDR_PRESENT = 1 << 0,
 	HTT_DATA_TX_DESC_FLAGS0_NO_AGGR         = 1 << 1,
@@ -1466,6 +1471,11 @@ struct ath10k_htt {
 
 	/* rx_status template */
 	struct ieee80211_rx_status rx_status;
+
+	struct {
+		dma_addr_t paddr;
+		struct htt_msdu_ext_desc *vaddr;
+	} frag_desc;
 };
 
 #define RX_HTT_HDR_STATUS_LEN 64
@@ -1533,6 +1543,7 @@ void ath10k_htt_htc_tx_complete(struct ath10k *ar, struct sk_buff *skb);
 void ath10k_htt_t2h_msg_handler(struct ath10k *ar, struct sk_buff *skb);
 int ath10k_htt_h2t_ver_req_msg(struct ath10k_htt *htt);
 int ath10k_htt_h2t_stats_req(struct ath10k_htt *htt, u8 mask, u64 cookie);
+int ath10k_htt_send_frag_desc_bank_cfg(struct ath10k_htt *htt);
 int ath10k_htt_send_rx_ring_cfg_ll(struct ath10k_htt *htt);
 int ath10k_htt_h2t_aggr_cfg_msg(struct ath10k_htt *htt,
 				u8 max_subfrms_ampdu,

drivers/net/wireless/ath/ath10k/htt_tx.c

@@ -84,6 +84,7 @@ void ath10k_htt_tx_free_msdu_id(struct ath10k_htt *htt, u16 msdu_id)
 int ath10k_htt_tx_alloc(struct ath10k_htt *htt)
 {
 	struct ath10k *ar = htt->ar;
+	int ret, size;
 
 	ath10k_dbg(ar, ATH10K_DBG_BOOT, "htt tx max num pending tx %d\n",
 		   htt->max_num_pending_tx);
@@ -94,11 +95,31 @@ int ath10k_htt_tx_alloc(struct ath10k_htt *htt)
 	htt->tx_pool = dma_pool_create("ath10k htt tx pool", htt->ar->dev,
 				       sizeof(struct ath10k_htt_txbuf), 4, 0);
 	if (!htt->tx_pool) {
-		idr_destroy(&htt->pending_tx);
-		return -ENOMEM;
+		ret = -ENOMEM;
+		goto free_idr_pending_tx;
+	}
+
+	if (!ar->hw_params.continuous_frag_desc)
+		goto skip_frag_desc_alloc;
+
+	size = htt->max_num_pending_tx * sizeof(struct htt_msdu_ext_desc);
+	htt->frag_desc.vaddr = dma_alloc_coherent(ar->dev, size,
+						  &htt->frag_desc.paddr,
+						  GFP_DMA);
+	if (!htt->frag_desc.vaddr) {
+		ath10k_warn(ar, "failed to alloc fragment desc memory\n");
+		ret = -ENOMEM;
+		goto free_tx_pool;
 	}
 
+skip_frag_desc_alloc:
 	return 0;
+
+free_tx_pool:
+	dma_pool_destroy(htt->tx_pool);
+free_idr_pending_tx:
+	idr_destroy(&htt->pending_tx);
+	return ret;
 }
 
 static int ath10k_htt_tx_clean_up_pending(int msdu_id, void *skb, void *ctx)
@@ -121,9 +142,18 @@ static int ath10k_htt_tx_clean_up_pending(int msdu_id, void *skb, void *ctx)
 
 void ath10k_htt_tx_free(struct ath10k_htt *htt)
 {
+	int size;
+
 	idr_for_each(&htt->pending_tx, ath10k_htt_tx_clean_up_pending, htt->ar);
 	idr_destroy(&htt->pending_tx);
 	dma_pool_destroy(htt->tx_pool);
+
+	if (htt->frag_desc.vaddr) {
+		size = htt->max_num_pending_tx *
+				  sizeof(struct htt_msdu_ext_desc);
+		dma_free_coherent(htt->ar->dev, size, htt->frag_desc.vaddr,
+				  htt->frag_desc.paddr);
+	}
 }
 
 void ath10k_htt_htc_tx_complete(struct ath10k *ar, struct sk_buff *skb)
@@ -201,6 +231,48 @@ int ath10k_htt_h2t_stats_req(struct ath10k_htt *htt, u8 mask, u64 cookie)
 	return 0;
 }
 
+int ath10k_htt_send_frag_desc_bank_cfg(struct ath10k_htt *htt)
+{
+	struct ath10k *ar = htt->ar;
+	struct sk_buff *skb;
+	struct htt_cmd *cmd;
+	int ret, size;
+
+	if (!ar->hw_params.continuous_frag_desc)
+		return 0;
+
+	if (!htt->frag_desc.paddr) {
+		ath10k_warn(ar, "invalid frag desc memory\n");
+		return -EINVAL;
+	}
+
+	size = sizeof(cmd->hdr) + sizeof(cmd->frag_desc_bank_cfg);
+	skb = ath10k_htc_alloc_skb(ar, size);
+	if (!skb)
+		return -ENOMEM;
+
+	skb_put(skb, size);
+	cmd = (struct htt_cmd *)skb->data;
+	cmd->hdr.msg_type = HTT_H2T_MSG_TYPE_FRAG_DESC_BANK_CFG;
+	cmd->frag_desc_bank_cfg.info = 0;
+	cmd->frag_desc_bank_cfg.num_banks = 1;
+	cmd->frag_desc_bank_cfg.desc_size = sizeof(struct htt_msdu_ext_desc);
+	cmd->frag_desc_bank_cfg.bank_base_addrs[0] =
+				__cpu_to_le32(htt->frag_desc.paddr);
+	cmd->frag_desc_bank_cfg.bank_id[0].bank_max_id =
+				__cpu_to_le16(htt->max_num_pending_tx - 1);
+
+	ret = ath10k_htc_send(&htt->ar->htc, htt->eid, skb);
+	if (ret) {
+		ath10k_warn(ar, "failed to send frag desc bank cfg request: %d\n",
+			    ret);
+		dev_kfree_skb_any(skb);
+		return ret;
+	}
+
+	return 0;
+}
+
 int ath10k_htt_send_rx_ring_cfg_ll(struct ath10k_htt *htt)
 {
 	struct ath10k *ar = htt->ar;