ata: ceva: Add CCI support for SATA if CCI is enabled

This patch adds support for CCI in SATA controller if CCI is
enabled in design. This patch will add CCI settings for SATA
if "dma-coherent" dts property is added.
Signed-off-by: Anurag Kumar Vulisha <anuragku@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

drivers/ata/ahci_ceva.c

@@ -32,6 +32,7 @@
 #define AHCI_VEND_PP3C  0xB0
 #define AHCI_VEND_PP4C  0xB4
 #define AHCI_VEND_PP5C  0xB8
+#define AHCI_VEND_AXICC 0xBC
 #define AHCI_VEND_PAXIC 0xC0
 #define AHCI_VEND_PTC   0xC8
 
@@ -41,6 +42,15 @@
 #define PAXIC_MARIDD	(1 << 16)
 #define PAXIC_OTL	(0x4 << 20)
 
+/* Register bit definitions for cache control */
+#define AXICC_ARCA_VAL  (0xF << 0)
+#define AXICC_ARCF_VAL  (0xF << 4)
+#define AXICC_ARCH_VAL  (0xF << 8)
+#define AXICC_ARCP_VAL  (0xF << 12)
+#define AXICC_AWCFD_VAL (0xF << 16)
+#define AXICC_AWCD_VAL  (0xF << 20)
+#define AXICC_AWCF_VAL  (0xF << 24)
+
 #define PCFG_TPSS_VAL	(0x32 << 16)
 #define PCFG_TPRS_VAL	(0x2 << 12)
 #define PCFG_PAD_VAL	0x2
@@ -82,6 +92,9 @@ struct ceva_ahci_priv {
 	u32 pp3c[NR_PORTS];
 	u32 pp4c[NR_PORTS];
 	u32 pp5c[NR_PORTS];
+	/* Axi Cache Control Register */
+	u32 axicc;
+	bool is_cci_enabled;
 	int flags;
 };
 
@@ -139,6 +152,16 @@ static void ahci_ceva_setup(struct ahci_host_priv *hpriv)
 		tmp = PCFG_TPSS_VAL | PCFG_TPRS_VAL | (PCFG_PAD_VAL + i);
 		writel(tmp, mmio + AHCI_VEND_PCFG);
 
+		/* Set AXI cache control register if CCi is enabled */
+		if (cevapriv->is_cci_enabled) {
+			tmp = readl(mmio + AHCI_VEND_AXICC);
+			tmp |= AXICC_ARCA_VAL | AXICC_ARCF_VAL |
+				AXICC_ARCH_VAL | AXICC_ARCP_VAL |
+				AXICC_AWCFD_VAL | AXICC_AWCD_VAL |
+				AXICC_AWCF_VAL;
+			writel(tmp, mmio + AHCI_VEND_AXICC);
+		}
+
 		/* Port Phy Cfg register enables */
 		tmp = PPCFG_TTA | PPCFG_PSS_EN | PPCFG_ESDF_EN;
 		writel(tmp, mmio + AHCI_VEND_PPCFG);
@@ -177,6 +200,7 @@ static int ceva_ahci_probe(struct platform_device *pdev)
 	struct device *dev = &pdev->dev;
 	struct ahci_host_priv *hpriv;
 	struct ceva_ahci_priv *cevapriv;
+	enum dev_dma_attr attr;
 	int rc;
 
 	cevapriv = devm_kzalloc(dev, sizeof(*cevapriv), GFP_KERNEL);
@@ -248,6 +272,13 @@ static int ceva_ahci_probe(struct platform_device *pdev)
 		return -EINVAL;
 	}
 
+	/*
+	 * Check if CCI is enabled for SATA. The DEV_DMA_COHERENT is returned
+	 * if CCI is enabled, so check for DEV_DMA_COHERENT.
+	 */
+	attr = device_get_dma_attr(dev);
+	cevapriv->is_cci_enabled = (attr == DEV_DMA_COHERENT);
+
 	hpriv->plat_data = cevapriv;
 
 	/* CEVA specific initialization */