WIP: AHCI driver

src/drivers/ata/ahci_elphel.c

+/*
+ * Elphel AHCI SATA platform driver for elphel393 camera
+ *
+ * Based on the AHCI SATA platform driver by Jeff Garzik and Anton Vorontsov
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ */
+
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/ahci_platform.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/slab.h>
+#include <linux/platform_device.h>
+#include <linux/dma-mapping.h>
+#include "ahci.h"
+
+#define DRV_NAME "elphel-ahci"
+#define MARKER "+"
+
+/* Property names from device tree, these are specific for the controller */
+#define PROP_NAME_CLB_OFFS "clb_offs"
+#define PROP_NAME_FB_OFFS "fb_offs"
+
+static struct ata_port_operations ahci_elphel_ops;
+static const struct ata_port_info ahci_elphel_port_info;
+static struct scsi_host_template ahci_platform_sht;
+static const struct of_device_id ahci_elphel_of_match[];
+
+struct elphel_ahci_priv {
+	u32 clb_offs;
+	u32 fb_offs;
+};
+
+static int elphel_port_start(struct ata_port *ap)
+{
+	void *mem;
+	dma_addr_t mem_dma;
+	struct device *dev = ap->host->dev;
+	struct ahci_port_priv *pp;
+	struct ahci_host_priv *hpriv = ap->host->private_data;
+	const struct elphel_ahci_priv *dpriv = hpriv->plat_data;
+
+	dev_info(dev, "starting port %d", ap->port_no);
+	/*pp = devm_kzalloc(dev, sizeof(struct ahci_port_priv), GFP_KERNEL);
+	if (!pp)
+		return -ENOMEM;
+
+	mem = dmam_alloc_coherent(dev, AHCI_CMD_TBL_AR_SZ, &mem_dma, GFP_KERNEL);
+	if (!mem)
+		return -ENOMEM;
+	memset(mem, 0, AHCI_CMD_TBL_AR_SZ);
+	pp->cmd_tbl = mem;
+	pp->cmd_tbl_dma = mem_dma;*/
+
+	/*
+	 * Set predefined addresses
+	 */
+	/*pp->cmd_slot = hpriv->mmio + dpriv->clb_offs;
+	pp->cmd_slot_dma = virt_to_phys(pp->cmd_slot);
+
+	pp->rx_fis = hpriv->mmio + dpriv->fb_offs;
+	pp->rx_fis_dma = virt_to_phys(pp->rx_fis);*/
+
+	/*
+	 * Save off initial list of interrupts to be enabled.
+	 * This could be changed later
+	 */
+	/*pp->intr_mask = DEF_PORT_IRQ;
+
+	ap->private_data = pp;
+
+	return ahci_port_resume(ap);*/
+	return 0;
+}
+
+static int elphel_parse_prop(const struct device_node *devn,
+		struct device *dev,
+		struct elphel_ahci_priv *dpriv)
+{
+	const __be32 *val;
+
+	if (!devn) {
+		dev_err(dev, "device tree node is not found");
+		return -EINVAL;
+	}
+
+	val = of_get_property(devn, PROP_NAME_CLB_OFFS, NULL);
+	dpriv->clb_offs = be32_to_cpup(val);
+	val = of_get_property(devn, PROP_NAME_FB_OFFS, NULL);
+	dpriv->fb_offs = be32_to_cpup(val);
+
+	return 0;
+}
+
+static int elphel_drv_probe(struct platform_device *pdev)
+{
+	int ret;
+	struct ahci_host_priv *hpriv;
+	struct elphel_ahci_priv *drv_priv;
+	struct device *dev = &pdev->dev;
+	const struct of_device_id *match;
+	void __iomem *mmio = NULL;
+
+	struct resource *res;
+
+	dev_info(&pdev->dev, "probing Elphel AHCI driver");
+	drv_priv = devm_kzalloc(dev, sizeof(struct elphel_ahci_priv), GFP_KERNEL);
+	if (!drv_priv)
+		return -ENOMEM;
+
+	match = of_match_device(ahci_elphel_of_match, &pdev->dev);
+	if (!match)
+		return -EINVAL;
+
+	ret = elphel_parse_prop(dev->of_node, dev, drv_priv);
+	if (ret != 0)
+		return ret;
+
+	/*hpriv = ahci_platform_get_resources(pdev);
+	if (IS_ERR(hpriv))
+		return PTR_ERR(hpriv);
+	hpriv->plat_data = drv_priv;
+	dev_info(dev, "ahci platform resources set");*/
+
+	dev_info(dev, "get IORESOURCE_MEM");
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res) {
+		dev_err(dev, "can not get resourse");
+		return -EINVAL;
+	}
+	dev_info(dev, "resource name: %s", res->name);
+	dev_info(dev, "resource start: 0x%08x", res->start);
+	dev_info(dev, "resource end: 0x%08x", res->end);
+
+	/*mmio = hpriv->mmio;
+	if (!mmio) {
+		dev_err(dev, "mmio pointer is not initialized");
+		ahci_platform_disable_resources(hpriv);
+		return -EINVAL;
+	}
+	dev_info(dev, "mmio pointer: 0x%08p", mmio);
+	dev_info(dev, "HOST CAP register: 0x%08x", readl(mmio + HOST_CAP));
+	ahci_platform_disable_resources(hpriv);*/
+
+	/*ret = ahci_platform_init_host(pdev, hpriv, &ahci_elphel_port_info,
+			&ahci_platform_sht);
+	if (ret) {
+		ahci_platform_disable_resources(hpriv);
+		return ret;
+	}
+	dev_info(dev, "ahci platform host initialized");*/
+
+	return 0;
+}
+
+static int elphel_drv_remove(struct platform_device *pdev)
+{
+	dev_info(&pdev->dev, "removing Elphel AHCI driver");
+	//ata_platform_remove_one(pdev);
+}
+
+static struct ata_port_operations ahci_elphel_ops = {
+		.inherits		= &ahci_ops,
+		.port_start		= elphel_port_start,
+};
+
+static const struct ata_port_info ahci_elphel_port_info = {
+		.flags			= AHCI_FLAG_COMMON,
+		.pio_mask		= ATA_PIO4,
+		.udma_mask		= ATA_UDMA6,
+		.port_ops		= &ahci_elphel_ops,
+};
+
+static struct scsi_host_template ahci_platform_sht = {
+		AHCI_SHT(DRV_NAME),
+};
+
+static const struct of_device_id ahci_elphel_of_match[] = {
+		{ .compatible = "elphel,elphel-ahci", },
+		{ /* end of list */ }
+};
+MODULE_DEVICE_TABLE(of, ahci_elphel_of_match);
+
+static struct platform_driver ahci_elphel_driver = {
+		.probe			= elphel_drv_probe,
+		/*.remove			= ata_platform_remove_one,*/
+		.remove			= elphel_drv_remove,
+		.driver	= {
+				.name	= DRV_NAME,
+				.owner	= THIS_MODULE,
+				.of_match_table	= ahci_elphel_of_match,
+		},
+};
+module_platform_driver(ahci_elphel_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Elphel, Inc.");
+MODULE_DESCRIPTION("Elphel AHCI SATA platform driver for elphel393 camera");