text: // SPDX-License-Identifier: (GPL-2.0 OR MIT)
  /*
   * Copyright (c) 2018 Synopsys, Inc. and/or its affiliates.
   * stmmac HW Interface Handling
   */
  
  #include "common.h"
  #include "stmmac.h"
  #include "stmmac_ptp.h"
  
  static u32 stmmac_get_id(struct stmmac_priv *priv, u32 id_reg)
  {
  	u32 reg = readl(priv->ioaddr + id_reg);
  
  	if (!reg) {
  		dev_info(priv->device, "Version ID not available\n");
  		return 0x0;
  	}
  
  	dev_info(priv->device, "User ID: 0x%x, Synopsys ID: 0x%x\n",
  			(unsigned int)(reg & GENMASK(15, 8)) >> 8,
  			(unsigned int)(reg & GENMASK(7, 0)));
  	return reg & GENMASK(7, 0);
  }
  
  static void stmmac_dwmac_mode_quirk(struct stmmac_priv *priv)
  {
  	struct mac_device_info *mac = priv->hw;
  
  	if (priv->chain_mode) {
  		dev_info(priv->device, "Chain mode enabled\n");
  		priv->mode = STMMAC_CHAIN_MODE;
  		mac->mode = &chain_mode_ops;
  	} else {
  		dev_info(priv->device, "Ring mode enabled\n");
  		priv->mode = STMMAC_RING_MODE;
  		mac->mode = &ring_mode_ops;
  	}
  }
  
  static int stmmac_dwmac1_quirks(struct stmmac_priv *priv)
  {
  	struct mac_device_info *mac = priv->hw;
  
  	if (priv->plat->enh_desc) {
  		dev_info(priv->device, "Enhanced/Alternate descriptors\n");
  
  		/* GMAC older than 3.50 has no extended descriptors */
  		if (priv->synopsys_id >= DWMAC_CORE_3_50) {
  			dev_info(priv->device, "Enabled extended descriptors\n");
  			priv->extend_desc = 1;
  		} else {
  			dev_warn(priv->device, "Extended descriptors not supported\n");
  		}
  
  		mac->desc = &enh_desc_ops;
  	} else {
  		dev_info(priv->device, "Normal descriptors\n");
  		mac->desc = &ndesc_ops;
  	}
  
  	stmmac_dwmac_mode_quirk(priv);
  	return 0;
  }
  
  static int stmmac_dwmac4_quirks(struct stmmac_priv *priv)
  {
  	stmmac_dwmac_mode_quirk(priv);
  	return 0;
  }
  
  static const struct stmmac_hwif_entry {
  	bool gmac;
  	bool gmac4;
  	bool xgmac;
  	u32 min_id;
  	const struct stmmac_regs_off regs;
  	const void *desc;
  	const void *dma;
  	const void *mac;
  	const void *hwtimestamp;
  	const void *mode;
  	const void *tc;
  	int (*setup)(struct stmmac_priv *priv);
  	int (*quirks)(struct stmmac_priv *priv);
  } stmmac_hw[] = {
  	/* NOTE: New HW versions shall go to the end of this table */
  	{
  		.gmac = false,
  		.gmac4 = false,
  		.xgmac = false,
  		.min_id = 0,
  		.regs = {
  			.ptp_off = PTP_GMAC3_X_OFFSET,
  			.mmc_off = MMC_GMAC3_X_OFFSET,
  		},
  		.desc = NULL,
  		.dma = &dwmac100_dma_ops,
  		.mac = &dwmac100_ops,
  		.hwtimestamp = &stmmac_ptp,
  		.mode = NULL,
  		.tc = NULL,
  		.setup = dwmac100_setup,
  		.quirks = stmmac_dwmac1_quirks,
  	}, {
  		.gmac = true,
  		.gmac4 = false,
  		.xgmac = false,
  		.min_id = 0,
  		.regs = {
  			.ptp_off = PTP_GMAC3_X_OFFSET,
  			.mmc_off = MMC_GMAC3_X_OFFSET,
  		},
  		.desc = NULL,
  		.dma = &dwmac1000_dma_ops,
  		.mac = &dwmac1000_ops,
  		.hwtimestamp = &stmmac_ptp,
  		.mode = NULL,
  		.tc = NULL,
  		.setup = dwmac1000_setup,
  		.quirks = stmmac_dwmac1_quirks,
  	}, {
  		.gmac = false,
  		.gmac4 = true,
  		.xgmac = false,
  		.min_id = 0,
  		.regs = {
  			.ptp_off = PTP_GMAC4_OFFSET,
  			.mmc_off = MMC_GMAC4_OFFSET,
  		},
  		.desc = &dwmac4_desc_ops,
  		.dma = &dwmac4_dma_ops,
  		.mac = &dwmac4_ops,
  		.hwtimestamp = &stmmac_ptp,
  		.mode = NULL,
  		.tc = NULL,
  		.setup = dwmac4_setup,
  		.quirks = stmmac_dwmac4_quirks,
  	}, {
  		.gmac = false,
  		.gmac4 = true,
  		.xgmac = false,
  		.min_id = DWMAC_CORE_4_00,
  		.regs = {
  			.ptp_off = PTP_GMAC4_OFFSET,
  			.mmc_off = MMC_GMAC4_OFFSET,
  		},
  		.desc = &dwmac4_desc_ops,
  		.dma = &dwmac4_dma_ops,
  		.mac = &dwmac410_ops,
  		.hwtimestamp = &stmmac_ptp,
  		.mode = &dwmac4_ring_mode_ops,
  		.tc = NULL,
  		.setup = dwmac4_setup,
  		.quirks = NULL,
  	}, {
  		.gmac = false,
  		.gmac4 = true,
  		.xgmac = false,
  		.min_id = DWMAC_CORE_4_10,
  		.regs = {
  			.ptp_off = PTP_GMAC4_OFFSET,
  			.mmc_off = MMC_GMAC4_OFFSET,
  		},
  		.desc = &dwmac4_desc_ops,
  		.dma = &dwmac410_dma_ops,
  		.mac = &dwmac410_ops,
  		.hwtimestamp = &stmmac_ptp,
  		.mode = &dwmac4_ring_mode_ops,
  		.tc = NULL,
  		.setup = dwmac4_setup,
  		.quirks = NULL,
  	}, {
  		.gmac = false,
  		.gmac4 = true,
  		.xgmac = false,
  		.min_id = DWMAC_CORE_5_10,
  		.regs = {
  			.ptp_off = PTP_GMAC4_OFFSET,
  			.mmc_off = MMC_GMAC4_OFFSET,
  		},
  		.desc = &dwmac4_desc_ops,
  		.dma = &dwmac410_dma_ops,
  		.mac = &dwmac510_ops,
  		.hwtimestamp = &stmmac_ptp,
  		.mode = &dwmac4_ring_mode_ops,
  		.tc = &dwmac510_tc_ops,
  		.setup = dwmac4_setup,
  		.quirks = NULL,
  	}, {
  		.gmac = false,
  		.gmac4 = false,
  		.xgmac = true,
  		.min_id = DWXGMAC_CORE_2_10,
  		.regs = {
  			.ptp_off = PTP_XGMAC_OFFSET,
  			.mmc_off = 0,
  		},
  		.desc = &dwxgmac210_desc_ops,
  		.dma = &dwxgmac210_dma_ops,
  		.mac = &dwxgmac210_ops,
  		.hwtimestamp = &stmmac_ptp,
  		.mode = NULL,
  		.tc = NULL,
  		.setup = dwxgmac2_setup,
  		.quirks = NULL,
  	},
  };
  
  int stmmac_hwif_init(struct stmmac_priv *priv)
  {
  	bool needs_xgmac = priv->plat->has_xgmac;
  	bool needs_gmac4 = priv->plat->has_gmac4;
  	bool needs_gmac = priv->plat->has_gmac;
  	const struct stmmac_hwif_entry *entry;
  	struct mac_device_info *mac;
  	bool needs_setup = true;
  	int i, ret;
  	u32 id;
  
  	if (needs_gmac) {
  		id = stmmac_get_id(priv, GMAC_VERSION);
  	} else if (needs_gmac4 || needs_xgmac) {
  		id = stmmac_get_id(priv, GMAC4_VERSION);
  	} else {
  		id = 0;
  	}
  
  	/* Save ID for later use */
  	priv->synopsys_id = id;
  
  	/* Lets assume some safe values first */
  	priv->ptpaddr = priv->ioaddr +
  		(needs_gmac4 ? PTP_GMAC4_OFFSET : PTP_GMAC3_X_OFFSET);
  	priv->mmcaddr = priv->ioaddr +
  		(needs_gmac4 ? MMC_GMAC4_OFFSET : MMC_GMAC3_X_OFFSET);
  
  	/* Check for HW specific setup first */
  	if (priv->plat->setup) {
  		mac = priv->plat->setup(priv);
  		needs_setup = false;
  	} else {
  		mac = devm_kzalloc(priv->device, sizeof(*mac), GFP_KERNEL);
  	}
  
  	if (!mac)
  		return -ENOMEM;
  
  	/* Fallback to generic HW */
  	for (i = ARRAY_SIZE(stmmac_hw) - 1; i >= 0; i--) {
  		entry = &stmmac_hw[i];
  
  		if (needs_gmac ^ entry->gmac)
  			continue;
  		if (needs_gmac4 ^ entry->gmac4)
  			continue;
  		if (needs_xgmac ^ entry->xgmac)
  			continue;
  		/* Use synopsys_id var because some setups can override this */
  		if (priv->synopsys_id < entry->min_id)
  			continue;
  
  		/* Only use generic HW helpers if needed */
  		mac->desc = mac->desc ? : entry->desc;
  		mac->dma = mac->dma ? : entry->dma;
  		mac->mac = mac->mac ? : entry->mac;
  		mac->ptp = mac->ptp ? : entry->hwtimestamp;
  		mac->mode = mac->mode ? : entry->mode;
  		mac->tc = mac->tc ? : entry->tc;
  
  		priv->hw = mac;
  		priv->ptpaddr = priv->ioaddr + entry->regs.ptp_off;
  		priv->mmcaddr = priv->ioaddr + entry->regs.mmc_off;
  
  		/* Entry found */
  		if (needs_setup) {
  			ret = entry->setup(priv);
  			if (ret)
  				return ret;
  		}
  
  		/* Save quirks, if needed for posterior use */
  		priv->hwif_quirks = entry->quirks;
  		return 0;
  	}
  
  	dev_err(priv->device, "Failed to find HW IF (id=0x%x, gmac=%d/%d)\n",
  			id, needs_gmac, needs_gmac4);
  	return -EINVAL;
  }
  