drivers/net/ethernet/stmicro/stmmac/dwxgmac2_descs.c

// SPDX-License-Identifier: (GPL-2.0 OR MIT)
/*
 * Copyright (c) 2018 Synopsys, Inc. and/or its affiliates.
 * stmmac XGMAC support.
 */

#include <linux/stmmac.h>
#include "common.h"
#include "dwxgmac2.h"

static int dwxgmac2_get_tx_status(void *data, struct stmmac_extra_stats *x,
				  struct dma_desc *p, void __iomem *ioaddr)
{
	unsigned int tdes3 = le32_to_cpu(p->des3);
	int ret = tx_done;

	if (unlikely(tdes3 & XGMAC_TDES3_OWN))
		return tx_dma_own;
	if (likely(!(tdes3 & XGMAC_TDES3_LD)))
		return tx_not_ls;

	return ret;
}

static int dwxgmac2_get_rx_status(void *data, struct stmmac_extra_stats *x,
				  struct dma_desc *p)
{
	unsigned int rdes3 = le32_to_cpu(p->des3);
	int ret = good_frame;

	if (unlikely(rdes3 & XGMAC_RDES3_OWN))
		return dma_own;
	if (likely(!(rdes3 & XGMAC_RDES3_LD)))
		return discard_frame;
	if (unlikely(rdes3 & XGMAC_RDES3_ES))
		ret = discard_frame;

	return ret;
}

static int dwxgmac2_get_tx_len(struct dma_desc *p)
{
	return (le32_to_cpu(p->des2) & XGMAC_TDES2_B1L);
}

static int dwxgmac2_get_tx_owner(struct dma_desc *p)
{
	return (le32_to_cpu(p->des3) & XGMAC_TDES3_OWN) > 0;
}

static void dwxgmac2_set_tx_owner(struct dma_desc *p)
{
	p->des3 |= cpu_to_le32(XGMAC_TDES3_OWN);
}

static void dwxgmac2_set_rx_owner(struct dma_desc *p, int disable_rx_ic)
{
	p->des3 = cpu_to_le32(XGMAC_RDES3_OWN);

	if (!disable_rx_ic)
		p->des3 |= cpu_to_le32(XGMAC_RDES3_IOC);
}

static int dwxgmac2_get_tx_ls(struct dma_desc *p)
{
	return (le32_to_cpu(p->des3) & XGMAC_RDES3_LD) > 0;
}

static int dwxgmac2_get_rx_frame_len(struct dma_desc *p, int rx_coe)
{
	return (le32_to_cpu(p->des3) & XGMAC_RDES3_PL);
}

static void dwxgmac2_enable_tx_timestamp(struct dma_desc *p)
{
	p->des2 |= cpu_to_le32(XGMAC_TDES2_TTSE);
}

static int dwxgmac2_get_tx_timestamp_status(struct dma_desc *p)
{
	return 0; /* Not supported */
}

static inline void dwxgmac2_get_timestamp(void *desc, u32 ats, u64 *ts)
{
	struct dma_desc *p = (struct dma_desc *)desc;
	u64 ns = 0;

	ns += le32_to_cpu(p->des1) * 1000000000ULL;
	ns += le32_to_cpu(p->des0);

	*ts = ns;
}

static int dwxgmac2_rx_check_timestamp(void *desc)
{
	struct dma_desc *p = (struct dma_desc *)desc;
	unsigned int rdes3 = le32_to_cpu(p->des3);
	bool desc_valid, ts_valid;

	desc_valid = !(rdes3 & XGMAC_RDES3_OWN) && (rdes3 & XGMAC_RDES3_CTXT);
	ts_valid = !(rdes3 & XGMAC_RDES3_TSD) && (rdes3 & XGMAC_RDES3_TSA);

	if (likely(desc_valid && ts_valid))
		return 0;
	return -EINVAL;
}

static int dwxgmac2_get_rx_timestamp_status(void *desc, void *next_desc,
					    u32 ats)
{
	struct dma_desc *p = (struct dma_desc *)desc;
	unsigned int rdes3 = le32_to_cpu(p->des3);
	int ret = -EBUSY;

	if (likely(rdes3 & XGMAC_RDES3_CDA)) {
		ret = dwxgmac2_rx_check_timestamp(next_desc);
		if (ret)
			return ret;
	}

	return ret;
}

static void dwxgmac2_init_rx_desc(struct dma_desc *p, int disable_rx_ic,
				  int mode, int end, int bfsize)
{
	dwxgmac2_set_rx_owner(p, disable_rx_ic);
}

static void dwxgmac2_init_tx_desc(struct dma_desc *p, int mode, int end)
{
	p->des0 = 0;
	p->des1 = 0;
	p->des2 = 0;
	p->des3 = 0;
}

static void dwxgmac2_prepare_tx_desc(struct dma_desc *p, int is_fs, int len,
				     bool csum_flag, int mode, bool tx_own,
				     bool ls, unsigned int tot_pkt_len)
{
	unsigned int tdes3 = le32_to_cpu(p->des3);

	p->des2 |= cpu_to_le32(len & XGMAC_TDES2_B1L);

	tdes3 = tot_pkt_len & XGMAC_TDES3_FL;
	if (is_fs)
		tdes3 |= XGMAC_TDES3_FD;
	else
		tdes3 &= ~XGMAC_TDES3_FD;

	if (csum_flag)
		tdes3 |= 0x3 << XGMAC_TDES3_CIC_SHIFT;
	else
		tdes3 &= ~XGMAC_TDES3_CIC;

	if (ls)
		tdes3 |= XGMAC_TDES3_LD;
	else
		tdes3 &= ~XGMAC_TDES3_LD;

	/* Finally set the OWN bit. Later the DMA will start! */
	if (tx_own)
		tdes3 |= XGMAC_TDES3_OWN;

	if (is_fs && tx_own)
		/* When the own bit, for the first frame, has to be set, all
		 * descriptors for the same frame has to be set before, to
		 * avoid race condition.
		 */
		dma_wmb();

	p->des3 = cpu_to_le32(tdes3);
}

static void dwxgmac2_prepare_tso_tx_desc(struct dma_desc *p, int is_fs,
					 int len1, int len2, bool tx_own,
					 bool ls, unsigned int tcphdrlen,
					 unsigned int tcppayloadlen)
{
	unsigned int tdes3 = le32_to_cpu(p->des3);

	if (len1)
		p->des2 |= cpu_to_le32(len1 & XGMAC_TDES2_B1L);
	if (len2)
		p->des2 |= cpu_to_le32((len2 << XGMAC_TDES2_B2L_SHIFT) &
				XGMAC_TDES2_B2L);
	if (is_fs) {
		tdes3 |= XGMAC_TDES3_FD | XGMAC_TDES3_TSE;
		tdes3 |= (tcphdrlen << XGMAC_TDES3_THL_SHIFT) &
			XGMAC_TDES3_THL;
		tdes3 |= tcppayloadlen & XGMAC_TDES3_TPL;
	} else {
		tdes3 &= ~XGMAC_TDES3_FD;
	}

	if (ls)
		tdes3 |= XGMAC_TDES3_LD;
	else
		tdes3 &= ~XGMAC_TDES3_LD;

	/* Finally set the OWN bit. Later the DMA will start! */
	if (tx_own)
		tdes3 |= XGMAC_TDES3_OWN;

	if (is_fs && tx_own)
		/* When the own bit, for the first frame, has to be set, all
		 * descriptors for the same frame has to be set before, to
		 * avoid race condition.
		 */
		dma_wmb();

	p->des3 = cpu_to_le32(tdes3);
}

static void dwxgmac2_release_tx_desc(struct dma_desc *p, int mode)
{
	p->des0 = 0;
	p->des1 = 0;
	p->des2 = 0;
	p->des3 = 0;
}

static void dwxgmac2_set_tx_ic(struct dma_desc *p)
{
	p->des2 |= cpu_to_le32(XGMAC_TDES2_IOC);
}

static void dwxgmac2_set_mss(struct dma_desc *p, unsigned int mss)
{
	p->des0 = 0;
	p->des1 = 0;
	p->des2 = cpu_to_le32(mss);
	p->des3 = cpu_to_le32(XGMAC_TDES3_CTXT | XGMAC_TDES3_TCMSSV);
}

static void dwxgmac2_get_addr(struct dma_desc *p, unsigned int *addr)
{
	*addr = le32_to_cpu(p->des0);
}

static void dwxgmac2_set_addr(struct dma_desc *p, dma_addr_t addr)
{
	p->des0 = cpu_to_le32(addr);
	p->des1 = 0;
}

static void dwxgmac2_clear(struct dma_desc *p)
{
	p->des0 = 0;
	p->des1 = 0;
	p->des2 = 0;
	p->des3 = 0;
}

const struct stmmac_desc_ops dwxgmac210_desc_ops = {
	.tx_status = dwxgmac2_get_tx_status,
	.rx_status = dwxgmac2_get_rx_status,
	.get_tx_len = dwxgmac2_get_tx_len,
	.get_tx_owner = dwxgmac2_get_tx_owner,
	.set_tx_owner = dwxgmac2_set_tx_owner,
	.set_rx_owner = dwxgmac2_set_rx_owner,
	.get_tx_ls = dwxgmac2_get_tx_ls,
	.get_rx_frame_len = dwxgmac2_get_rx_frame_len,
	.enable_tx_timestamp = dwxgmac2_enable_tx_timestamp,
	.get_tx_timestamp_status = dwxgmac2_get_tx_timestamp_status,
	.get_rx_timestamp_status = dwxgmac2_get_rx_timestamp_status,
	.get_timestamp = dwxgmac2_get_timestamp,
	.set_tx_ic = dwxgmac2_set_tx_ic,
	.prepare_tx_desc = dwxgmac2_prepare_tx_desc,
	.prepare_tso_tx_desc = dwxgmac2_prepare_tso_tx_desc,
	.release_tx_desc = dwxgmac2_release_tx_desc,
	.init_rx_desc = dwxgmac2_init_rx_desc,
	.init_tx_desc = dwxgmac2_init_tx_desc,
	.set_mss = dwxgmac2_set_mss,
	.get_addr = dwxgmac2_get_addr,
	.set_addr = dwxgmac2_set_addr,
	.clear = dwxgmac2_clear,
};