ata: ahci_tegra: Add AHCI support for Tegra186

This patch adds support for AHCI-compliant Serial ATA controller
on Tegra186 SoC.

Tegra186 does not have sata-oob reset.
Tegra186 SATA_NVOOB register filed COMMA_CNT position and width are
different compared to Tegra210 and prior.

So, this patch adds a flag has_sata_oob_rst and tegra_ahci_regs to
SoC specific strcuture tegra_ahci_soc and updated their implementation
accordingly.

Signed-off-by: Sowjanya Komatineni <[e-mail]>
Acked-by: Thierry Reding <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Jens Axboe <[e-mail]>

drivers/ata/ahci_tegra.c

···
 #define T_SATA0_CFG_PHY_1_PAD_PLL_IDDQ_EN		BIT(22)
 
 #define T_SATA0_NVOOB                                   0x114
-#define T_SATA0_NVOOB_COMMA_CNT_MASK                    (0xff << 16)
-#define T_SATA0_NVOOB_COMMA_CNT                         (0x07 << 16)
 #define T_SATA0_NVOOB_SQUELCH_FILTER_MODE_MASK          (0x3 << 24)
 #define T_SATA0_NVOOB_SQUELCH_FILTER_MODE               (0x1 << 24)
 #define T_SATA0_NVOOB_SQUELCH_FILTER_LENGTH_MASK        (0x3 << 26)
···
 	int (*init)(struct ahci_host_priv *hpriv);
 };
 
+struct tegra_ahci_regs {
+	unsigned int nvoob_comma_cnt_mask;
+	unsigned int nvoob_comma_cnt_val;
+};
+
 struct tegra_ahci_soc {
 	const char *const		*supply_names;
 	u32				num_supplies;
 	bool				supports_devslp;
+	bool				has_sata_oob_rst;
 	const struct tegra_ahci_ops	*ops;
+	const struct tegra_ahci_regs	*regs;
 };
 
 struct tegra_ahci_priv {
···
 	if (ret)
 		return ret;
 
-	ret = tegra_powergate_sequence_power_up(TEGRA_POWERGATE_SATA,
-						tegra->sata_clk,
-						tegra->sata_rst);
-	if (ret)
-		goto disable_regulators;
+	if (!tegra->pdev->dev.pm_domain) {
+		ret = tegra_powergate_sequence_power_up(TEGRA_POWERGATE_SATA,
+							tegra->sata_clk,
+							tegra->sata_rst);
+		if (ret)
+			goto disable_regulators;
+	}
 
 	reset_control_assert(tegra->sata_oob_rst);
 	reset_control_assert(tegra->sata_cold_rst);
···
 	writel(val, tegra->sata_regs + SCFG_OFFSET + T_SATA_CFG_PHY_0);
 
 	val = readl(tegra->sata_regs + SCFG_OFFSET + T_SATA0_NVOOB);
-	val &= ~(T_SATA0_NVOOB_COMMA_CNT_MASK |
+	val &= ~(tegra->soc->regs->nvoob_comma_cnt_mask |
 		 T_SATA0_NVOOB_SQUELCH_FILTER_LENGTH_MASK |
 		 T_SATA0_NVOOB_SQUELCH_FILTER_MODE_MASK);
-	val |= (T_SATA0_NVOOB_COMMA_CNT |
+	val |= (tegra->soc->regs->nvoob_comma_cnt_val |
 		T_SATA0_NVOOB_SQUELCH_FILTER_LENGTH |
 		T_SATA0_NVOOB_SQUELCH_FILTER_MODE);
 	writel(val, tegra->sata_regs + SCFG_OFFSET + T_SATA0_NVOOB);
···
 	.init = tegra124_ahci_init,
 };
 
+static const struct tegra_ahci_regs tegra124_ahci_regs = {
+	.nvoob_comma_cnt_mask = GENMASK(30, 28),
+	.nvoob_comma_cnt_val = (7 << 28),
+};
+
 static const struct tegra_ahci_soc tegra124_ahci_soc = {
 	.supply_names = tegra124_supply_names,
 	.num_supplies = ARRAY_SIZE(tegra124_supply_names),
 	.supports_devslp = false,
+	.has_sata_oob_rst = true,
 	.ops = &tegra124_ahci_ops,
+	.regs = &tegra124_ahci_regs,
 };
 
 static const struct tegra_ahci_soc tegra210_ahci_soc = {
 	.supports_devslp = false,
+	.has_sata_oob_rst = true,
+	.regs = &tegra124_ahci_regs,
+};
+
+static const struct tegra_ahci_regs tegra186_ahci_regs = {
+	.nvoob_comma_cnt_mask = GENMASK(23, 16),
+	.nvoob_comma_cnt_val = (7 << 16),
+};
+
+static const struct tegra_ahci_soc tegra186_ahci_soc = {
+	.supports_devslp = false,
+	.has_sata_oob_rst = false,
+	.regs = &tegra186_ahci_regs,
 };
 
 static const struct of_device_id tegra_ahci_of_match[] = {
···
 	{
 		.compatible = "nvidia,tegra210-ahci",
 		.data = &tegra210_ahci_soc
+	},
+	{
+		.compatible = "nvidia,tegra186-ahci",
+		.data = &tegra186_ahci_soc
 	},
 	{}
 };
···
 		return PTR_ERR(tegra->sata_rst);
 	}
 
-	tegra->sata_oob_rst = devm_reset_control_get(&pdev->dev, "sata-oob");
-	if (IS_ERR(tegra->sata_oob_rst)) {
-		dev_err(&pdev->dev, "Failed to get sata-oob reset\n");
-		return PTR_ERR(tegra->sata_oob_rst);
+	if (tegra->soc->has_sata_oob_rst) {
+		tegra->sata_oob_rst = devm_reset_control_get(&pdev->dev,
+							     "sata-oob");
+		if (IS_ERR(tegra->sata_oob_rst)) {
+			dev_err(&pdev->dev, "Failed to get sata-oob reset\n");
+			return PTR_ERR(tegra->sata_oob_rst);
+		}
 	}
 
 	tegra->sata_cold_rst = devm_reset_control_get(&pdev->dev, "sata-cold");