Re: [Patch v2 5/5] drivers/net: support hdlc function for QE-UCC

The driver add hdlc support for Freescale QUICC Engine.
It support NMSI and TSA mode.

Signed-off-by: Zhao Qiang <qiang.zhao@nxp.com>
---
Changes for v2:
	- remove useless code.
	- remove Unnecessary casts
	- return IRQ_NONE when there are no interrupt
	- remove Useless comments

 MAINTAINERS                    |    7 +
 drivers/net/wan/Kconfig        |   11 +
 drivers/net/wan/Makefile       |    1 +
 drivers/net/wan/fsl_ucc_hdlc.c | 1189 ++++++++++++++++++++++++++++++++++++++++
 drivers/net/wan/fsl_ucc_hdlc.h |  147 +++++
 include/soc/fsl/qe/qe.h        |    1 +
 include/soc/fsl/qe/ucc_fast.h  |   21 +-
 7 files changed, 1375 insertions(+), 2 deletions(-)
 create mode 100644 drivers/net/wan/fsl_ucc_hdlc.c
 create mode 100644 drivers/net/wan/fsl_ucc_hdlc.h

diff --git a/MAINTAINERS b/MAINTAINERS
index 74bbff3..bdada16 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS

@@ -4572,6 +4572,13 @@ F:	drivers/net/ethernet/freescale/gianfar*

 X:	drivers/net/ethernet/freescale/gianfar_ptp.c
 F:	Documentation/devicetree/bindings/net/fsl-tsec-phy.txt
 
+FREESCALE QUICC ENGINE UCC HDLC DRIVER
+M:	Zhao Qiang [off-list ref]
+L:	netdev@vger.kernel.org
+L:	linuxppc-dev@lists.ozlabs.org
+S:	Maintained
+F:	drivers/net/wan/fsl_ucc_hdlc*
+
 FREESCALE QUICC ENGINE UCC UART DRIVER
 M:	Timur Tabi [off-list ref]
 L:	linuxppc-dev@lists.ozlabs.org

diff --git a/drivers/net/wan/Kconfig b/drivers/net/wan/Kconfig
index a2fdd15..9e314b7 100644
--- a/drivers/net/wan/Kconfig
+++ b/drivers/net/wan/Kconfig

@@ -280,6 +280,17 @@ config DSCC4

 	  To compile this driver as a module, choose M here: the
 	  module will be called dscc4.
 
+config FSL_UCC_HDLC
+	tristate "Freescale QUICC Engine HDLC support"
+	depends on HDLC
+	depends on QUICC_ENGINE
+	help
+	  Driver for Freescale QUICC Engine HDLC controller. The driver
+	  supports HDLC in NMSI and TDM mode.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called fsl_ucc_hdlc.
+
 config DSCC4_PCISYNC
 	bool "Etinc PCISYNC features"
 	depends on DSCC4

diff --git a/drivers/net/wan/Makefile b/drivers/net/wan/Makefile
index c135ef4..25fec40 100644
--- a/drivers/net/wan/Makefile
+++ b/drivers/net/wan/Makefile

@@ -32,6 +32,7 @@ obj-$(CONFIG_WANXL)		+= wanxl.o

 obj-$(CONFIG_PCI200SYN)		+= pci200syn.o
 obj-$(CONFIG_PC300TOO)		+= pc300too.o
 obj-$(CONFIG_IXP4XX_HSS)	+= ixp4xx_hss.o
+obj-$(CONFIG_FSL_UCC_HDLC)	+= fsl_ucc_hdlc.o
 
 clean-files := wanxlfw.inc
 $(obj)/wanxl.o:	$(obj)/wanxlfw.inc

diff --git a/drivers/net/wan/fsl_ucc_hdlc.c b/drivers/net/wan/fsl_ucc_hdlc.c
new file mode 100644
index 0000000..f72634d
--- /dev/null
+++ b/drivers/net/wan/fsl_ucc_hdlc.c

@@ -0,0 +1,1189 @@
+/* Freescale QUICC Engine HDLC Device Driver
+ *
+ * Copyright 2016 Freescale Semiconductor Inc.
+ *
+ * This program is free software; you can redistribute  it and/or modify it
+ * under  the terms of  the GNU General  Public License as published by the
+ * Free Software Foundation;  either version 2 of the  License, or (at your
+ * option) any later version.
+ */
+
+#include <linux/delay.h>
+#include <linux/dma-mapping.h>
+#include <linux/hdlc.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/sched.h>
+#include <linux/skbuff.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/stddef.h>
+#include <soc/fsl/qe/qe_tdm.h>
+#include <uapi/linux/if_arp.h>
+
+#include "fsl_ucc_hdlc.h"
+
+#define DRV_DESC "Freescale QE UCC HDLC Driver"
+#define DRV_NAME "ucc_hdlc"
+
+#define TDM_PPPOHT_SLIC_MAXIN
+#define BROKEN_FRAME_INFO
+
+static struct ucc_tdm_info utdm_primary_info = {
+	.uf_info = {
+		.tsa = 0,
+		.cdp = 0,
+		.cds = 1,
+		.ctsp = 1,
+		.ctss = 1,
+		.revd = 0,
+		.urfs = 256,
+		.utfs = 256,
+		.urfet = 128,
+		.urfset = 192,
+		.utfet = 128,
+		.utftt = 0x40,
+		.ufpt = 256,
+		.mode = UCC_FAST_PROTOCOL_MODE_HDLC,
+		.ttx_trx = UCC_FAST_GUMR_TRANSPARENT_TTX_TRX_NORMAL,
+		.tenc = UCC_FAST_TX_ENCODING_NRZ,
+		.renc = UCC_FAST_RX_ENCODING_NRZ,
+		.tcrc = UCC_FAST_16_BIT_CRC,
+		.synl = UCC_FAST_SYNC_LEN_NOT_USED,
+	},
+
+	.si_info = {
+#ifdef TDM_PPPOHT_SLIC_MAXIN
+		.simr_rfsd = 1,
+		.simr_tfsd = 2,
+#else
+		.simr_rfsd = 0,
+		.simr_tfsd = 0,
+#endif
+		.simr_crt = 0,
+		.simr_sl = 0,
+		.simr_ce = 1,
+		.simr_fe = 1,
+		.simr_gm = 0,
+	},
+};
+
+static struct ucc_tdm_info utdm_info[MAX_HDLC_NUM];
+
+static int uhdlc_init(struct ucc_hdlc_private *priv)
+{
+	struct ucc_tdm_info *ut_info;
+	struct ucc_fast_info *uf_info;
+	u32 cecr_subblock;
+	u16 bd_status;
+	int ret, i;
+	void *bd_buffer;
+	dma_addr_t bd_dma_addr;
+	u32 riptr;
+	u32 tiptr;
+	u32 gumr;
+
+	ut_info = priv->ut_info;
+	uf_info = &ut_info->uf_info;
+
+	if (priv->tsa) {
+		uf_info->tsa = 1;
+		uf_info->ctsp = 1;
+	}
+	uf_info->uccm_mask = ((UCC_HDLC_UCCE_RXB | UCC_HDLC_UCCE_RXF |
+				UCC_HDLC_UCCE_TXB) << 16);
+
+	ret = ucc_fast_init(uf_info, &priv->uccf);
+	if (ret) {
+		dev_err(priv->dev, "Failed to init uccf.");
+		return ret;
+	}
+
+	priv->uf_regs = priv->uccf->uf_regs;
+	ucc_fast_disable(priv->uccf, COMM_DIR_RX | COMM_DIR_TX);
+
+	/* Loopback mode */
+	if (priv->loopback) {
+		dev_info(priv->dev, "Loopback Mode\n");
+		gumr = ioread32be(&priv->uf_regs->gumr);
+		gumr |= (UCC_FAST_GUMR_LOOPBACK | UCC_FAST_GUMR_CDS |
+			 UCC_FAST_GUMR_TCI);
+		gumr &= ~(UCC_FAST_GUMR_CTSP | UCC_FAST_GUMR_RSYN);
+		iowrite32be(gumr, &priv->uf_regs->gumr);
+	}
+
+	/* Initialize SI */
+	if (priv->tsa)
+		ucc_tdm_init(priv->utdm, priv->ut_info);
+
+	/* Write to QE CECR, UCCx channel to Stop Transmission */
+	cecr_subblock = ucc_fast_get_qe_cr_subblock(uf_info->ucc_num);
+	ret = qe_issue_cmd(QE_STOP_TX, cecr_subblock,
+			   QE_CR_PROTOCOL_UNSPECIFIED, 0);
+
+	/* Set UPSMR normal mode (need fixed)*/
+	iowrite32be(0, &priv->uf_regs->upsmr);
+
+	priv->rx_ring_size = RX_BD_RING_LEN;
+	priv->tx_ring_size = TX_BD_RING_LEN;
+	/* Alloc Rx BD */
+	priv->rx_bd_base = dma_alloc_coherent(priv->dev,
+			RX_BD_RING_LEN * sizeof(struct qe_bd *),
+			&priv->dma_rx_bd, GFP_KERNEL);
+
+	if (!priv->rx_bd_base) {
+		dev_err(priv->dev, "Cannot allocate MURAM memory for RxBDs\n");
+		ret = -ENOMEM;
+		goto rxbd_alloc_error;
+	}
+
+	/* Alloc Tx BD */
+	priv->tx_bd_base = dma_alloc_coherent(priv->dev,
+			TX_BD_RING_LEN * sizeof(struct qe_bd *),
+			&priv->dma_tx_bd, GFP_KERNEL);
+
+	if (!priv->tx_bd_base) {
+		dev_err(priv->dev, "Cannot allocate MURAM memory for TxBDs\n");
+		ret = -ENOMEM;
+		goto txbd_alloc_error;
+	}
+
+	/* Alloc parameter ram for ucc hdlc */
+	priv->ucc_pram_offset = qe_muram_alloc(sizeof(priv->ucc_pram),
+				ALIGNMENT_OF_UCC_HDLC_PRAM);
+
+	if (priv->ucc_pram_offset < 0) {
+		dev_err(priv->dev, "Can not allocate MURAM for hdlc prameter.\n");
+		ret = -ENOMEM;
+		goto pram_alloc_error;
+	}
+
+	priv->rx_skbuff = kzalloc(priv->rx_ring_size * sizeof(*priv->rx_skbuff),
+				  GFP_KERNEL);
+	if (!priv->rx_skbuff)
+		goto rx_skb_alloc_error;
+
+	priv->tx_skbuff = kzalloc(priv->tx_ring_size * sizeof(*priv->tx_skbuff),
+				  GFP_KERNEL);
+	if (!priv->tx_skbuff)
+		goto tx_skb_alloc_error;
+
+	priv->skb_curtx = 0;
+	priv->skb_dirtytx = 0;
+	priv->curtx_bd = priv->tx_bd_base;
+	priv->dirty_tx = priv->tx_bd_base;
+	priv->currx_bd = priv->rx_bd_base;
+	priv->currx_bdnum = 0;
+
+	/* init parameter base */
+	cecr_subblock = ucc_fast_get_qe_cr_subblock(uf_info->ucc_num);
+	ret = qe_issue_cmd(QE_ASSIGN_PAGE_TO_DEVICE, cecr_subblock,
+			   QE_CR_PROTOCOL_UNSPECIFIED, priv->ucc_pram_offset);
+
+	priv->ucc_pram = (struct ucc_hdlc_param __iomem *)
+					qe_muram_addr(priv->ucc_pram_offset);
+
+	/* Zero out parameter ram */
+	memset_io(priv->ucc_pram, 0, sizeof(struct ucc_hdlc_param));
+
+	/* Alloc riptr, tiptr */
+	riptr = qe_muram_alloc(32, 32);
+	if (riptr < 0) {
+		dev_err(priv->dev, "Cannot allocate MURAM mem for Receive internal temp data pointer\n");
+		ret = -ENOMEM;
+		goto riptr_alloc_error;
+	}
+
+	tiptr = qe_muram_alloc(32, 32);
+	if (tiptr < 0) {
+		dev_err(priv->dev, "Cannot allocate MURAM mem for Transmit internal temp data pointer\n");
+		ret = -ENOMEM;
+		goto tiptr_alloc_error;
+	}
+
+	/* Set RIPTR, TIPTR */
+	iowrite16be(riptr, &priv->ucc_pram->riptr);
+	iowrite16be(tiptr, &priv->ucc_pram->tiptr);
+
+	/* Set MRBLR */
+	iowrite16be(MAX_RX_BUF_LENGTH, &priv->ucc_pram->mrblr);
+
+	/* Set RBASE, TBASE */
+	iowrite32be(priv->dma_rx_bd, &priv->ucc_pram->rbase);
+	iowrite32be(priv->dma_tx_bd, &priv->ucc_pram->tbase);
+
+	/* Set RSTATE, TSTATE */
+	iowrite32be(BMR_GBL | BMR_BIG_ENDIAN, &priv->ucc_pram->rstate);
+	iowrite32be(BMR_GBL | BMR_BIG_ENDIAN, &priv->ucc_pram->tstate);
+
+	/* Set C_MASK, C_PRES for 16bit CRC */
+	iowrite32be(CRC_16BIT_MASK, &priv->ucc_pram->c_mask);
+	iowrite32be(CRC_16BIT_PRES, &priv->ucc_pram->c_pres);
+
+	iowrite16be(MAX_FRAME_LENGTH, &priv->ucc_pram->mflr);
+	iowrite16be(DEFAULT_RFTHR, &priv->ucc_pram->rfthr);
+	iowrite16be(DEFAULT_RFTHR, &priv->ucc_pram->rfcnt);
+	iowrite16be(DEFAULT_ADDR_MASK, &priv->ucc_pram->hmask);
+	iowrite16be(DEFAULT_HDLC_ADDR, &priv->ucc_pram->haddr1);
+	iowrite16be(DEFAULT_HDLC_ADDR, &priv->ucc_pram->haddr2);
+	iowrite16be(DEFAULT_HDLC_ADDR, &priv->ucc_pram->haddr3);
+	iowrite16be(DEFAULT_HDLC_ADDR, &priv->ucc_pram->haddr4);
+
+	/* Get BD buffer */
+	bd_buffer = dma_alloc_coherent(priv->dev,
+				       (RX_BD_RING_LEN + TX_BD_RING_LEN) *
+				       MAX_RX_BUF_LENGTH,
+				       &bd_dma_addr, GFP_KERNEL);
+
+	if (!bd_buffer) {
+		dev_err(priv->dev, "Could not allocate buffer descriptors\n");
+		ret = -ENOMEM;
+		goto bd_alloc_error;
+	}
+
+	memset(bd_buffer, 0, (RX_BD_RING_LEN + TX_BD_RING_LEN)
+			* MAX_RX_BUF_LENGTH);
+
+	priv->rx_buffer = bd_buffer;
+	priv->tx_buffer = bd_buffer + RX_BD_RING_LEN * MAX_RX_BUF_LENGTH;
+
+	priv->dma_rx_addr = bd_dma_addr;
+	priv->dma_tx_addr = bd_dma_addr + RX_BD_RING_LEN * MAX_RX_BUF_LENGTH;
+
+	for (i = 0; i < RX_BD_RING_LEN; i++) {
+		if (i < (RX_BD_RING_LEN - 1))
+			bd_status = R_E_S | R_I_S;
+		else
+			bd_status = R_E_S | R_I_S | R_W_S;
+
+		iowrite16be(bd_status, &priv->rx_bd_base[i].status);
+		iowrite32be(priv->dma_rx_addr + i * MAX_RX_BUF_LENGTH,
+			    &priv->rx_bd_base[i].buf);
+	}
+
+	for (i = 0; i < TX_BD_RING_LEN; i++) {
+		if (i < (TX_BD_RING_LEN - 1))
+			bd_status =  T_I_S | T_TC_S;
+		else
+			bd_status =  T_I_S | T_TC_S | T_W_S;
+
+		iowrite16be(bd_status, &priv->tx_bd_base[i].status);
+		iowrite32be(priv->dma_tx_addr + i * MAX_RX_BUF_LENGTH,
+			    &priv->tx_bd_base[i].buf);
+	}
+
+	return 0;
+
+bd_alloc_error:
+	qe_muram_free(tiptr);
+tiptr_alloc_error:
+	qe_muram_free(riptr);
+riptr_alloc_error:
+	kfree(priv->tx_skbuff);
+tx_skb_alloc_error:
+	kfree(priv->rx_skbuff);
+rx_skb_alloc_error:
+	qe_muram_free(priv->ucc_pram_offset);
+pram_alloc_error:
+	dma_free_coherent(priv->dev,
+			  TX_BD_RING_LEN * sizeof(struct qe_bd),
+			  priv->tx_bd_base, priv->dma_tx_bd);
+txbd_alloc_error:
+	dma_free_coherent(priv->dev,
+			  RX_BD_RING_LEN * sizeof(struct qe_bd),
+			  priv->rx_bd_base, priv->dma_rx_bd);
+rxbd_alloc_error:
+	ucc_fast_free(priv->uccf);
+
+	return ret;
+}
+
+static netdev_tx_t ucc_hdlc_tx(struct sk_buff *skb, struct net_device *dev)
+{
+	hdlc_device *hdlc = dev_to_hdlc(dev);
+	struct ucc_hdlc_private *priv = (struct ucc_hdlc_private *)hdlc->priv;
+	struct qe_bd __iomem *bd;
+	u16 bd_status;
+	unsigned long flags;
+	u8 *send_buf;
+	int i;
+	u16 *proto_head;
+
+	switch (dev->type) {
+	case ARPHRD_RAWHDLC:
+		if (skb_headroom(skb) < HDLC_HEAD_LEN) {
+			dev->stats.tx_dropped++;
+			dev_kfree_skb(skb);
+			netdev_err(dev, "No enough space for hdlc head\n");
+			return -ENOMEM;
+		}
+
+		skb_push(skb, HDLC_HEAD_LEN);
+
+		proto_head = (u16 *)skb->data;
+		*proto_head = htons(DEFAULT_HDLC_HEAD);
+
+		dev->stats.tx_bytes += skb->len;
+		break;
+
+	case ARPHRD_PPP:
+		proto_head = (u16 *)skb->data;
+		if (*proto_head != htons(DEFAULT_PPP_HEAD)) {
+			dev->stats.tx_dropped++;
+			dev_kfree_skb(skb);
+			netdev_err(dev, "Wrong ppp header\n");
+			return -ENOMEM;
+		}
+
+		dev->stats.tx_bytes += skb->len;
+		break;
+
+	default:
+		dev->stats.tx_dropped++;
+		dev_kfree_skb(skb);
+		return -ENOMEM;
+	}
+
+	pr_info("Tx data skb->len:%d ", skb->len);
+	send_buf = (u8 *)skb->data;
+	pr_info("\nTransmitted data:\n");
+	for (i = 0; i < 16; i++) {
+		if (i == skb->len)
+			pr_info("++++");
+		else
+		pr_info("%02x\n", send_buf[i]);
+	}
+	spin_lock_irqsave(&priv->lock, flags);
+
+	/* Start from the next BD that should be filled */
+	bd = priv->curtx_bd;
+	bd_status = ioread16be(&bd->status);
+	/* Save the skb pointer so we can free it later */
+	priv->tx_skbuff[priv->skb_curtx] = skb;
+
+	/* Update the current skb pointer (wrapping if this was the last) */
+	priv->skb_curtx =
+	    (priv->skb_curtx + 1) & TX_RING_MOD_MASK(TX_BD_RING_LEN);
+
+	/* copy skb data to tx buffer for sdma processing */
+	memcpy(priv->tx_buffer + (be32_to_cpu(bd->buf) - priv->dma_tx_addr),
+	       skb->data, skb->len);
+
+	/* set bd status and length */
+	bd_status = (bd_status & T_W_S) | T_R_S | T_I_S | T_L_S | T_TC_S;
+
+	iowrite16be(bd_status, &bd->status);
+	iowrite16be(skb->len, &bd->length);