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Diffstat (limited to 'drivers/ata/ahci_sunxi.c')
-rw-r--r--drivers/ata/ahci_sunxi.c68
1 files changed, 52 insertions, 16 deletions
diff --git a/drivers/ata/ahci_sunxi.c b/drivers/ata/ahci_sunxi.c
index b26437430163..5d4584570ae0 100644
--- a/drivers/ata/ahci_sunxi.c
+++ b/drivers/ata/ahci_sunxi.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-only
/*
* Allwinner sunxi AHCI SATA platform driver
* Copyright 2013 Olliver Schinagl <oliver@schinagl.nl>
@@ -6,23 +7,14 @@
* based on the AHCI SATA platform driver by Jeff Garzik and Anton Vorontsov
* Based on code from Allwinner Technology Co., Ltd. <www.allwinnertech.com>,
* Daniel Wang <danielwang@allwinnertech.com>
- *
- * 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/ahci_platform.h>
#include <linux/clk.h>
#include <linux/errno.h>
#include <linux/kernel.h>
+#include <linux/mod_devicetable.h>
#include <linux/module.h>
-#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/regulator/consumer.h>
#include "ahci.h"
@@ -157,21 +149,64 @@ static void ahci_sunxi_start_engine(struct ata_port *ap)
void __iomem *port_mmio = ahci_port_base(ap);
struct ahci_host_priv *hpriv = ap->host->private_data;
- /* Setup DMA before DMA start */
- sunxi_clrsetbits(hpriv->mmio + AHCI_P0DMACR, 0x0000ff00, 0x00004400);
+ /* Setup DMA before DMA start
+ *
+ * NOTE: A similar SoC with SATA/AHCI by Texas Instruments documents
+ * this Vendor Specific Port (P0DMACR, aka PxDMACR) in its
+ * User's Guide document (TMS320C674x/OMAP-L1x Processor
+ * Serial ATA (SATA) Controller, Literature Number: SPRUGJ8C,
+ * March 2011, Chapter 4.33 Port DMA Control Register (P0DMACR),
+ * p.68, https://www.ti.com/lit/ug/sprugj8c/sprugj8c.pdf)
+ * as equivalent to the following struct:
+ *
+ * struct AHCI_P0DMACR_t
+ * {
+ * unsigned TXTS : 4;
+ * unsigned RXTS : 4;
+ * unsigned TXABL : 4;
+ * unsigned RXABL : 4;
+ * unsigned Reserved : 16;
+ * };
+ *
+ * TXTS: Transmit Transaction Size (TX_TRANSACTION_SIZE).
+ * This field defines the DMA transaction size in DWORDs for
+ * transmit (system bus read, device write) operation. [...]
+ *
+ * RXTS: Receive Transaction Size (RX_TRANSACTION_SIZE).
+ * This field defines the Port DMA transaction size in DWORDs
+ * for receive (system bus write, device read) operation. [...]
+ *
+ * TXABL: Transmit Burst Limit.
+ * This field allows software to limit the VBUSP master read
+ * burst size. [...]
+ *
+ * RXABL: Receive Burst Limit.
+ * Allows software to limit the VBUSP master write burst
+ * size. [...]
+ *
+ * Reserved: Reserved.
+ *
+ *
+ * NOTE: According to the above document, the following alternative
+ * to the code below could perhaps be a better option
+ * (or preparation) for possible further improvements later:
+ * sunxi_clrsetbits(hpriv->mmio + AHCI_P0DMACR, 0x0000ffff,
+ * 0x00000033);
+ */
+ sunxi_clrsetbits(hpriv->mmio + AHCI_P0DMACR, 0x0000ffff, 0x00004433);
/* Start DMA */
sunxi_setbits(port_mmio + PORT_CMD, PORT_CMD_START);
}
static const struct ata_port_info ahci_sunxi_port_info = {
- .flags = AHCI_FLAG_COMMON | ATA_FLAG_NCQ,
+ .flags = AHCI_FLAG_COMMON | ATA_FLAG_NCQ | ATA_FLAG_NO_DIPM,
.pio_mask = ATA_PIO4,
.udma_mask = ATA_UDMA6,
.port_ops = &ahci_platform_ops,
};
-static struct scsi_host_template ahci_platform_sht = {
+static const struct scsi_host_template ahci_platform_sht = {
AHCI_SHT(DRV_NAME),
};
@@ -181,7 +216,7 @@ static int ahci_sunxi_probe(struct platform_device *pdev)
struct ahci_host_priv *hpriv;
int rc;
- hpriv = ahci_platform_get_resources(pdev);
+ hpriv = ahci_platform_get_resources(pdev, AHCI_PLATFORM_GET_RESETS);
if (IS_ERR(hpriv))
return PTR_ERR(hpriv);
@@ -250,7 +285,8 @@ static SIMPLE_DEV_PM_OPS(ahci_sunxi_pm_ops, ahci_platform_suspend,
static const struct of_device_id ahci_sunxi_of_match[] = {
{ .compatible = "allwinner,sun4i-a10-ahci", },
- { },
+ { .compatible = "allwinner,sun8i-r40-ahci", },
+ { /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, ahci_sunxi_of_match);