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@@ -1,94 +0,0 @@
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-From 120357ea176e420d313cf8cf2ff35fbe233d3bab Mon Sep 17 00:00:00 2001
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-From: Uenal Mutlu <[email protected]>
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-Date: Mon, 13 May 2019 16:24:10 +0200
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-Subject: [PATCH] drivers: ata: ahci_sunxi: Increased SATA/AHCI DMA TX/RX FIFOs
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-
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-Increasing the SATA/AHCI DMA TX/RX FIFOs (P0DMACR.TXTS and .RXTS, ie.
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-TX_TRANSACTION_SIZE and RX_TRANSACTION_SIZE) from default 0x0 each
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-to 0x3 each, gives a write performance boost of 120 MiB/s to 132 MiB/s
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-from lame 36 MiB/s to 45 MiB/s previously.
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-Read performance is above 200 MiB/s.
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-[tested on SSD using dd bs=4K/8K/12K/16K/20K/24K/32K: peak-perf at 12K]
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-
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-Tested on the SBCs Banana Pi R1 (aka Lamobo R1) and Banana Pi M1 which
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-are based on the Allwinner A20 32bit-SoC (ARMv7-a / arm-linux-gnueabihf).
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-These devices are RaspberryPi-like small devices.
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-
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-This problem of slow SATA write-speed with these small devices lasts
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-for about 7 years now (beginning with the A10 SoC). Many commentators
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-throughout the years wrongly assumed the slow write speed was a
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-hardware limitation. This patch finally solves the problem, which
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-in fact was just a hard-to-find software problem due to lack of
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-SATA/AHCI documentation by the SoC-maker Allwinner Technology.
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-
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-Lists of the affected sunxi and other boards and SoCs with SATA using
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-the ahci_sunxi driver:
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- $ grep -i -e "^&ahci" arch/arm/boot/dts/sun*dts
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- and http://linux-sunxi.org/SATA#Devices_with_SATA_ports
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- See also http://linux-sunxi.org/Category:Devices_with_SATA_port
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-
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-Tested-by: Chen-Yu Tsai <[email protected]>
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-Acked-by: Maxime Ripard <[email protected]>
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-Reviewed-by: Hans de Goede <[email protected]>
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-Signed-off-by: Uenal Mutlu <[email protected]>
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-Signed-off-by: Jens Axboe <[email protected]>
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----
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- drivers/ata/ahci_sunxi.c | 47 ++++++++++++++++++++++++++++++++++++++--
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- 1 file changed, 45 insertions(+), 2 deletions(-)
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-
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---- a/drivers/ata/ahci_sunxi.c
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-+++ b/drivers/ata/ahci_sunxi.c
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-@@ -157,8 +157,51 @@ static void ahci_sunxi_start_engine(stru
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- void __iomem *port_mmio = ahci_port_base(ap);
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- struct ahci_host_priv *hpriv = ap->host->private_data;
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-
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-- /* Setup DMA before DMA start */
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-- sunxi_clrsetbits(hpriv->mmio + AHCI_P0DMACR, 0x0000ff00, 0x00004400);
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-+ /* Setup DMA before DMA start
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-+ *
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-+ * NOTE: A similar SoC with SATA/AHCI by Texas Instruments documents
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-+ * this Vendor Specific Port (P0DMACR, aka PxDMACR) in its
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-+ * User's Guide document (TMS320C674x/OMAP-L1x Processor
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-+ * Serial ATA (SATA) Controller, Literature Number: SPRUGJ8C,
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-+ * March 2011, Chapter 4.33 Port DMA Control Register (P0DMACR),
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-+ * p.68, https://www.ti.com/lit/ug/sprugj8c/sprugj8c.pdf)
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-+ * as equivalent to the following struct:
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-+ *
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-+ * struct AHCI_P0DMACR_t
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-+ * {
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-+ * unsigned TXTS : 4;
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-+ * unsigned RXTS : 4;
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-+ * unsigned TXABL : 4;
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-+ * unsigned RXABL : 4;
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-+ * unsigned Reserved : 16;
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-+ * };
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-+ *
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-+ * TXTS: Transmit Transaction Size (TX_TRANSACTION_SIZE).
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-+ * This field defines the DMA transaction size in DWORDs for
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-+ * transmit (system bus read, device write) operation. [...]
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-+ *
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-+ * RXTS: Receive Transaction Size (RX_TRANSACTION_SIZE).
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-+ * This field defines the Port DMA transaction size in DWORDs
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-+ * for receive (system bus write, device read) operation. [...]
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-+ *
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-+ * TXABL: Transmit Burst Limit.
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-+ * This field allows software to limit the VBUSP master read
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-+ * burst size. [...]
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-+ *
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-+ * RXABL: Receive Burst Limit.
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-+ * Allows software to limit the VBUSP master write burst
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-+ * size. [...]
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-+ *
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-+ * Reserved: Reserved.
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-+ *
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-+ *
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-+ * NOTE: According to the above document, the following alternative
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-+ * to the code below could perhaps be a better option
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-+ * (or preparation) for possible further improvements later:
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-+ * sunxi_clrsetbits(hpriv->mmio + AHCI_P0DMACR, 0x0000ffff,
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-+ * 0x00000033);
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-+ */
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-+ sunxi_clrsetbits(hpriv->mmio + AHCI_P0DMACR, 0x0000ffff, 0x00004433);
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-
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- /* Start DMA */
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- sunxi_setbits(port_mmio + PORT_CMD, PORT_CMD_START);
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