[PATCH v14 0/3] ata: Add APM X-Gene SoC AHCI SATA host controller support

[PATCH v14 0/3] ata: Add APM X-Gene SoC AHCI SATA host controller support

[Loc Ho]

This patch adds support for the APM X-Gene SoC AHCI SATA host controller. In
order for the host controller to work, the corresponding PHY driver
musts also be available.

v14:
 * Remove the shutdown already check and replace the while loop check with
   msleep in function xgene_ahci_init_memram

v13:
 * Add fully-winged style comment for function xgene_ahci_read_id and
   xgene_ahci_do_hardrest
 * Minor comments update for function xgene_ahci_read_id,
   xgene_ahci_do_hardrest, and xgene_ahci_hardreset
 * NOTE: There is no functional code change.

v12:
 * Remove function xgene_ahci_get_channel and use the ata_port field port_no
 * Update comment for function xgene_ahci_read_id to function comment style
   '/**'
 * Update comment for multiple lines to fully-winged style

v11:
 * Drop the export functions requirement with libachi
 * Change CONFIG_SATA_XGENE to CONFIG_AHCI_XGENE
 * Rename file sata_xgene.c to ahci_xgene.c
 * Convert to use Hans De Geode version 5 ahci_platform code re-factor changes
   to reduce code duplication. For extra context, use plat_data to store our
   context. The probe function follows the ahci_sunxi implementation. A number
   of code fragments update to reflect this change.
 * Update comment for function xgene_ahci_read_id
 * Minor code move around in function xgene_ahci_do_hardreset and use
   ATA_BUSY instead 0x80
 * Fix hardreset to use start_engine function pointer as required due to newer
   kernel rebased
 * Fix the set DMA mask for 32-bit as well

v10:
 * Update binding documentation

v9:
 * Remove ACPI/EFI include files
 * Remove the IO flush support, interrupt routine, and DTS resources
 * Remove function xgene_rd, xgene_wr, and xgene_wr_flush
 * Remove PMP support (function xgene_ahci_qc_issue, xgene_ahci_qc_prep,
   xgene_ahci_qc_fill_rtf, xgene_ahci_softreset, and xgene_ahci_do_softreset)
 * Rename function xgene_ahci_enable_phy to xgene_ahci_force_phy_rdy
 * Clean up hardreset functions
 * Require v7 of the PHY driver

v8:
 * Remove _ADDR from defines
 * Remove define MSTAWAUX_COHERENT_BYPASS_SET and
   STARAUX_COHERENT_BYPASS_SET and use direct coding
 * Remove the un-necessary check for DTS boot with built in ACPI table
 * Switch to use dma_set_mask_and_coherent for setting DMA mask
 * Remove ACPI table matching code
 * Update clock-names for sata01clk, sata23clk, and sata45clk

v7:
 * Update the clock code by toggle the clock
 * Update the DTS clock mask values due to the clock spilt between host and
   v5 of the PHY drivers

v6:
 * Update binding documentation
 * Change select PHY_XGENE_SATA to PHY_XGENE
 * Add ULL to constants
 * Change indentation and comments
 * Clean up the probe functions a bit more
 * Remove xgene_ahci_remove function
 * Add the flush register to DTS
 * Remove the interrupt-parent from DTS

v5:
 * Sync up to v3 of the PHY driver
 * Remove MSLIM wrapper functions
 * Change the memory shutdown loop to use usleep_range
 * Use devm_ioremap_resource instead devm_ioremap
 * Remove suspend/resume functions as not needed

v4:
 * Remove the ID property in DT
 * Remove the temporary PHY direct function call and use PHY function
 * Change printk to pr_debug
 * Move the IOB flush addresses into the DT
 * Remove the parameters retrieval function as no longer needed
 * Remove the header file as no longer needed
 * Require v2 patch of the SATA PHY driver. Require slightly modification
   in the Kconfig as it is moved to folder driver/phy and use Kconfig
   PHY_XGENE_SATA instead SATA_XGENE_PHY.

v3:
 * Move out the SATA PHY to another driver
 * Remove the clock-cells entry from DTS
 * Remove debug wrapper
 * Remove delay functions wrapper
 * Clean up resource and IRQ query
 * Remove query clock name
 * Switch to use dma_set_mask/dma_coherent_mask
 * Remove un-necessary devm_kfree
 * Update GPL license header to v2
 * Spilt up function xgene_ahci_hardreset
 * Spilt up function xgene_ahci_probe
 * Remove all reference of CONFIG_ARCH_MSLIM
 * Clean up chip revision code

v2:
 * Clean up file sata_xgene.c with Lindent and etc
 * Clean up file sata_xgene_serdes.c with Lindent and etc
 * Add description to each patch

v1:
 * inital version

Signed-off-by: Loc Ho <lho@apm.com>
Signed-off-by: Tuan Phan <tphan@apm.com>
Signed-off-by: Suman Tripathi <stripathi@apm.com>
---
Loc Ho (3):
  Documentation: Add documentation for APM X-Gene SoC SATA host
    controller DTS binding
  ata: Add APM X-Gene SoC AHCI SATA host controller driver
  arm64: Add APM X-Gene SoC AHCI SATA host controller DTS entries

 .../devicetree/bindings/ata/apm-xgene.txt          |   70 +++
 arch/arm64/boot/dts/apm-storm.dtsi                 |   75 +++
 drivers/ata/Kconfig                                |    8 +
 drivers/ata/Makefile                               |    1 +
 drivers/ata/ahci_xgene.c                           |  566 ++++++++++++++++++++
 5 files changed, 720 insertions(+), 0 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/ata/apm-xgene.txt
 create mode 100644 drivers/ata/ahci_xgene.c

[PATCH v14 1/3] Documentation: Add documentation for APM X-Gene SoC SATA host controller DTS binding

[Loc Ho]

Signed-off-by: Loc Ho <lho@apm.com>
Signed-off-by: Tuan Phan <tphan@apm.com>
Signed-off-by: Suman Tripathi <stripathi@apm.com>
---
 .../devicetree/bindings/ata/apm-xgene.txt          |   70 ++++++++++++++++++++
 1 files changed, 70 insertions(+), 0 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/ata/apm-xgene.txt

diff --git a/Documentation/devicetree/bindings/ata/apm-xgene.txt b/Documentation/devicetree/bindings/ata/apm-xgene.txt
new file mode 100644
index 0000000..633eb3b
--- /dev/null
+++ b/Documentation/devicetree/bindings/ata/apm-xgene.txt
@@ -0,0 +1,70 @@
+* APM X-Gene 6.0 Gb/s SATA host controller nodes
+
+SATA host controller nodes are defined to describe on-chip Serial ATA
+controllers. Each SATA controller (pair of ports) have its own node.
+
+Required properties:
+- compatible		: Shall contain:
+  * "apm,xgene-ahci-sgmii" if mux'ed with SGMII
+  * "apm,xgene-ahci-pcie" if mux'ed with PCIe
+- reg			: First memory resource shall be the AHCI memory
+			  resource.
+			  Second memory resource shall be the host controller
+			  memory resource.
+- interrupts		: Interrupt-specifier for SATA host controller IRQ.
+- clocks		: Reference to the clock entry.
+- phys			: A list of phandles + phy-specifiers, one for each
+			  entry in phy-names.
+- phy-names		: Should contain:
+  * "sata-6g" for the SATA 6.0Gbps PHY
+
+Optional properties:
+- status		: Shall be "ok" if enabled or "disabled" if disabled.
+			  Default is "ok".
+- interrupt-parent	: Interrupt controller.
+
+Example:
+		sataclk: sataclk {
+			compatible = "fixed-clock";
+			#clock-cells = <1>;
+			clock-frequency = <100000000>;
+			clock-output-names = "sataclk";
+		};
+
+		phy2: phy@1f22a000 {
+			compatible = "apm,xgene-phy";
+			reg = <0x0 0x1f22a000 0x0 0x100>,
+			      <0x0 0x1f22c000 0x0 0x100>;
+			#phy-cells = <1>;
+		};
+
+		phy3: phy@1f23a000 {
+			compatible = "apm,xgene-phy";
+			reg = <0x0 0x1f23a000 0x0 0x100>,
+			      <0x0 0x1f23c000 0x0 0x100>;
+			#phy-cells = <1>;
+		};
+
+		sata2: sata@1a400000 {
+			compatible = "apm,xgene-ahci-sgmii";
+			reg = <0x0 0x1a400000 0x0 0x1000>,
+			      <0x0 0x1f220000 0x0 0x10000>;
+			interrupt-parent = <&gic>;
+			interrupts = <0x0 0x87 0x4>;
+			status = "ok";
+			clocks = <&sataclk 0>;
+			phys = <&phy2 0>;
+			phy-names = "sata-6g";
+		};
+
+		sata3: sata@1a800000 {
+			compatible = "apm,xgene-ahci-pcie";
+			reg = <0x0 0x1a800000 0x0 0x1000>,
+			      <0x0 0x1f230000 0x0 0x10000>;
+			interrupt-parent = <&gic>;
+			interrupts = <0x0 0x88 0x4>;
+			status = "ok";
+			clocks = <&sataclk 0>;
+			phys = <&phy3 0>;
+			phy-names = "sata-6g";
+		};
-- 
1.5.5

[PATCH v14 2/3] ata: Add APM X-Gene SoC AHCI SATA host controller driver

[Loc Ho]

This patch adds support for the APM X-Gene SoC AHCI SATA host controller
driver. It requires the corresponding APM X-Gene SoC PHY driver.

Signed-off-by: Loc Ho <lho@apm.com>
Signed-off-by: Tuan Phan <tphan@apm.com>
Signed-off-by: Suman Tripathi <stripathi@apm.com>
---
 drivers/ata/Kconfig      |    8 +
 drivers/ata/Makefile     |    1 +
 drivers/ata/ahci_xgene.c |  566 ++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 575 insertions(+), 0 deletions(-)
 create mode 100644 drivers/ata/ahci_xgene.c

diff --git a/drivers/ata/Kconfig b/drivers/ata/Kconfig
index cc67cc0..174e398 100644
--- a/drivers/ata/Kconfig
+++ b/drivers/ata/Kconfig
@@ -115,6 +115,14 @@ config AHCI_SUNXI
 
 	  If unsure, say N.
 
+config AHCI_XGENE
+	tristate "APM X-Gene 6.0Gbps AHCI SATA host controller support"
+	depends on ARM64 || COMPILE_TEST
+	select SATA_AHCI_PLATFORM
+	select PHY_XGENE
+	help
+	  This option enables support for APM X-Gene SoC SATA host controller.
+
 config SATA_FSL
 	tristate "Freescale 3.0Gbps SATA support"
 	depends on FSL_SOC
diff --git a/drivers/ata/Makefile b/drivers/ata/Makefile
index 246050b..72b423b 100644
--- a/drivers/ata/Makefile
+++ b/drivers/ata/Makefile
@@ -12,6 +12,7 @@ obj-$(CONFIG_SATA_DWC)		+= sata_dwc_460ex.o
 obj-$(CONFIG_SATA_HIGHBANK)	+= sata_highbank.o libahci.o
 obj-$(CONFIG_AHCI_IMX)		+= ahci_imx.o
 obj-$(CONFIG_AHCI_SUNXI)	+= ahci_sunxi.o
+obj-$(CONFIG_AHCI_XGENE)	+= ahci_xgene.o
 
 # SFF w/ custom DMA
 obj-$(CONFIG_PDC_ADMA)		+= pdc_adma.o
diff --git a/drivers/ata/ahci_xgene.c b/drivers/ata/ahci_xgene.c
new file mode 100644
index 0000000..36ba229
--- /dev/null
+++ b/drivers/ata/ahci_xgene.c
@@ -0,0 +1,566 @@
+/*
+ * AppliedMicro X-Gene SoC SATA Host Controller Driver
+ *
+ * Copyright (c) 2014, Applied Micro Circuits Corporation
+ * Author: Loc Ho <lho@apm.com>
+ *         Tuan Phan <tphan@apm.com>
+ *         Suman Tripathi <stripathi@apm.com>
+ *
+ * This program is free software; you can redistribute  it and/or modify it
+ * under  the terms of  the GNU General  Public License as published by the
+ * Free Software Foundation;  either version 2 of the  License, or (at your
+ * option) any later version.
+ *
+ * This program is distributed in the hope that 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/ahci_platform.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/phy/phy.h>
+#include "ahci.h"
+
+/* Controller who PHY shared with SGMII Ethernet PHY */
+#define XGENE_AHCI_SGMII_DTS		"apm,xgene-ahci-sgmii"
+
+/* Controller who PHY (internal reference clock macro) shared with PCIe */
+#define XGENE_AHCI_PCIE_DTS		"apm,xgene-ahci-pcie"
+
+/* Max # of disk per a controller */
+#define MAX_AHCI_CHN_PERCTR		2
+
+#define SATA_ENET_MUX_OFFSET		0x00007000
+#define SATA_DIAG_OFFSET		0x0000D000
+#define SATA_GLB_OFFSET			0x0000D850
+#define SATA_SHIM_OFFSET		0x0000E000
+#define SATA_MASTER_OFFSET		0x0000F000
+#define SATA_PORT0_OFFSET		0x00000100
+#define SATA_PORT1_OFFSET		0x00000180
+
+/* MUX CSR */
+#define SATA_ENET_CONFIG_REG		0x00000000
+#define  CFG_SATA_ENET_SELECT_MASK	0x00000001
+
+/* SATA host controller CSR */
+#define SLVRDERRATTRIBUTES		0x00000000
+#define SLVWRERRATTRIBUTES		0x00000004
+#define MSTRDERRATTRIBUTES		0x00000008
+#define MSTWRERRATTRIBUTES		0x0000000c
+#define BUSCTLREG			0x00000014
+#define IOFMSTRWAUX			0x00000018
+#define INTSTATUSMASK			0x0000002c
+#define ERRINTSTATUS			0x00000030
+#define ERRINTSTATUSMASK		0x00000034
+
+/* SATA host AHCI CSR */
+#define PORTCFG				0x000000a4
+#define  PORTADDR_SET(dst, src) \
+		(((dst) & ~0x0000003f) | (((u32)(src)) & 0x0000003f))
+#define PORTPHY1CFG		0x000000a8
+#define PORTPHY1CFG_FRCPHYRDY_SET(dst, src) \
+		(((dst) & ~0x00100000) | (((u32)(src) << 0x14) & 0x00100000))
+#define PORTPHY2CFG			0x000000ac
+#define PORTPHY3CFG			0x000000b0
+#define PORTPHY4CFG			0x000000b4
+#define PORTPHY5CFG			0x000000b8
+#define SCTL0				0x0000012C
+#define PORTPHY5CFG_RTCHG_SET(dst, src) \
+		(((dst) & ~0xfff00000) | (((u32)(src) << 0x14) & 0xfff00000))
+#define PORTAXICFG_EN_CONTEXT_SET(dst, src) \
+		(((dst) & ~0x01000000) | (((u32)(src) << 0x18) & 0x01000000))
+#define PORTAXICFG			0x000000bc
+#define PORTAXICFG_OUTTRANS_SET(dst, src) \
+		(((dst) & ~0x00f00000) | (((u32)(src) << 0x14) & 0x00f00000))
+
+/* SATA host controller slave CSR */
+#define INT_SLV_TMOMASK			0x00000010
+
+/* SATA global diagnostic CSR */
+#define CFG_MEM_RAM_SHUTDOWN		0x00000070
+#define BLOCK_MEM_RDY			0x00000074
+
+#define pdata_to_ctx(x) container_of(x, struct xgene_ahci_context, plat_data)
+
+struct xgene_ahci_context {
+	struct ahci_platform_data plat_data;
+	struct ahci_host_priv *hpriv;
+	struct device *dev;
+	void __iomem *csr_base;		/* CSR base address of IP */
+	struct phy *phy;
+};
+
+static int xgene_ahci_init_memram(struct xgene_ahci_context *ctx)
+{
+	void __iomem *diagcsr = ctx->csr_base + SATA_DIAG_OFFSET;
+
+	dev_dbg(ctx->dev, "Release memory from shutdown\n");
+	writel(0x0, diagcsr + CFG_MEM_RAM_SHUTDOWN);
+	readl(diagcsr + CFG_MEM_RAM_SHUTDOWN); /* Force a barrier */
+	msleep(1);	/* reset may take up to 1ms */
+	if (readl(diagcsr + BLOCK_MEM_RDY) != 0xFFFFFFFF) {
+		dev_err(ctx->dev, "failed to release memory from shutdown\n");
+		return -ENODEV;
+	}
+	return 0;
+}
+
+/**
+ * xgene_ahci_read_id - Read ID data from the specified device
+ * @dev: device
+ * @tf: proposed taskfile
+ * @id: data buffer
+ *
+ * This custom read ID function is required due to the fact that the HW
+ * does not support DEVSLP and the controller state machine may get stuck
+ * after processing the ID query command.
+ */
+static unsigned int xgene_ahci_read_id(struct ata_device *dev,
+				       struct ata_taskfile *tf, u16 *id)
+{
+	u32 err_mask;
+	void __iomem *port_mmio = ahci_port_base(dev->link->ap);
+
+	err_mask = ata_do_dev_read_id(dev, tf, id);
+	if (err_mask)
+		return err_mask;
+
+	/*
+	 * Mask reserved area. Bit78 spec of Link Power Management
+	 * bit15-8: reserved
+	 * bit7: NCQ autosence
+	 * bit6: Software settings preservation supported
+	 * bit5: reserved
+	 * bit4: In-order sata delivery supported
+	 * bit3: DIPM requests supported
+	 * bit2: DMA Setup FIS Auto-Activate optimization supported
+	 * bit1: DMA Setup FIX non-Zero buffer offsets supported
+	 * bit0: Reserved
+	 *
+	 * Clear reserved bit (DEVSLP bit) as we don't support DEVSLP
+	 */
+	id[78] &= 0x00FF;
+
+	/*
+	 * Due to HW errata, restart the port if no other command active.
+	 * Otherwise the controller may get stuck.
+	 */
+	if (!readl(port_mmio + PORT_CMD_ISSUE)) {
+		writel(PORT_CMD_FIS_RX, port_mmio + PORT_CMD);
+		readl(port_mmio + PORT_CMD);	/* Force a barrier */
+		writel(PORT_CMD_FIS_RX | PORT_CMD_START, port_mmio + PORT_CMD);
+		readl(port_mmio + PORT_CMD);	/* Force a barrier */
+	}
+	return 0;
+}
+
+static void xgene_ahci_force_phy_rdy(struct xgene_ahci_context *ctx,
+				     int channel, int force)
+{
+	void __iomem *mmio = ctx->hpriv->mmio;
+	u32 val;
+
+	val = readl(mmio + PORTCFG);
+	val = PORTADDR_SET(val, channel == 0 ? 2 : 3);
+	writel(val, mmio + PORTCFG);
+	readl(mmio + PORTCFG);	/* Force a barrier */
+	val = readl(mmio + PORTPHY1CFG);
+	val = PORTPHY1CFG_FRCPHYRDY_SET(val, force);
+	writel(val, mmio + PORTPHY1CFG);
+}
+
+static void xgene_ahci_set_phy_cfg(struct xgene_ahci_context *ctx, int channel)
+{
+	void __iomem *mmio = ctx->hpriv->mmio;
+	u32 val;
+
+	dev_dbg(ctx->dev, "port configure mmio 0x%p channel %d\n",
+		mmio, channel);
+	val = readl(mmio + PORTCFG);
+	val = PORTADDR_SET(val, channel == 0 ? 2 : 3);
+	writel(val, mmio + PORTCFG);
+	readl(mmio + PORTCFG);  /* Force a barrier */
+	/* Disable fix rate */
+	writel(0x0001fffe, mmio + PORTPHY1CFG);
+	readl(mmio + PORTPHY1CFG); /* Force a barrier */
+	writel(0x5018461c, mmio + PORTPHY2CFG);
+	readl(mmio + PORTPHY2CFG); /* Force a barrier */
+	writel(0x1c081907, mmio + PORTPHY3CFG);
+	readl(mmio + PORTPHY3CFG); /* Force a barrier */
+	writel(0x1c080815, mmio + PORTPHY4CFG);
+	readl(mmio + PORTPHY4CFG); /* Force a barrier */
+	/* Set window negotiation */
+	val = readl(mmio + PORTPHY5CFG);
+	val = PORTPHY5CFG_RTCHG_SET(val, 0x300);
+	writel(val, mmio + PORTPHY5CFG);
+	readl(mmio + PORTPHY5CFG); /* Force a barrier */
+	val = readl(mmio + PORTAXICFG);
+	val = PORTAXICFG_EN_CONTEXT_SET(val, 0x1); /* Enable context mgmt */
+	val = PORTAXICFG_OUTTRANS_SET(val, 0xe); /* Set outstanding */
+	writel(val, mmio + PORTAXICFG);
+	readl(mmio + PORTAXICFG); /* Force a barrier */
+}
+
+static int xgene_ahci_phy_restart(struct ata_link *link)
+{
+	struct ata_port *port = link->ap;
+	struct ahci_host_priv *hpriv = port->host->private_data;
+	struct xgene_ahci_context *ctx = pdata_to_ctx(hpriv->plat_data);
+
+	xgene_ahci_force_phy_rdy(ctx, port->port_no, 1);
+	xgene_ahci_force_phy_rdy(ctx, port->port_no, 0);
+	return 0;
+}
+
+/**
+ * xgene_ahci_do_hardreset - Issue the actual COMRESET
+ * @link: link to reset
+ * @deadline: deadline jiffies for the operation
+ * @online: Return value to indicate if device online
+ *
+ * Due to the limitation of the hardware PHY, a difference set of setting is
+ * required for each supported disk speed - Gen3 (6.0Gbps), Gen2 (3.0Gbps),
+ * and Gen1 (1.5Gbps). Otherwise during long IO stress test, the PHY will
+ * report disparity error and etc. In addition, during COMRESET, there can
+ * be error reported in the register PORT_SCR_ERR. For SERR_DISPARITY and
+ * SERR_10B_8B_ERR, the PHY receiver line must be reseted. The following
+ * algorithm is followed to proper configure the hardware PHY during COMRESET:
+ *
+ * Alg Part 1:
+ * 1. Start the PHY at Gen3 speed (default setting)
+ * 2. Issue the COMRESET
+ * 3. If no link, go to Alg Part 3
+ * 4. If link up, determine if the negotiated speed matches the PHY
+ *    configured speed
+ * 5. If they matched, go to Alg Part 2
+ * 6. If they do not matched and first time, configure the PHY for the linked
+ *    up disk speed and repeat step 2
+ * 7. Go to Alg Part 2
+ *
+ * Alg Part 2:
+ * 1. On link up, if there are any SERR_DISPARITY and SERR_10B_8B_ERR error
+ *    reported in the register PORT_SCR_ERR, then reset the PHY receiver line
+ * 2. Go to Alg Part 3
+ *
+ * Alg Part 3:
+ * 1. Clear any pending from register PORT_SCR_ERR.
+ */
+static int xgene_ahci_do_hardreset(struct ata_link *link,
+				   unsigned long deadline, bool *online)
+{
+	const unsigned long *timing = sata_ehc_deb_timing(&link->eh_context);
+	struct ata_port *ap = link->ap;
+	struct ahci_host_priv *hpriv = ap->host->private_data;
+	struct xgene_ahci_context *ctx = pdata_to_ctx(hpriv->plat_data);
+	struct ahci_port_priv *pp = ap->private_data;
+	u8 *d2h_fis = pp->rx_fis + RX_FIS_D2H_REG;
+	void __iomem *port_mmio = ahci_port_base(ap);
+	struct ata_taskfile tf;
+	int first_time = 1;
+	int rc;
+	u32 val;
+	int i;
+
+hardreset_retry:
+	/* clear D2H reception area to properly wait for D2H FIS */
+	ata_tf_init(link->device, &tf);
+	tf.command = ATA_BUSY;
+	ata_tf_to_fis(&tf, 0, 0, d2h_fis);
+	rc = sata_link_hardreset(link, timing, deadline, online,
+				 ahci_check_ready);
+
+	if (*online) {
+		/* Check to ensure that the disk comes up in matching speed */
+		if (first_time) {
+			u32 gen_speed;
+
+			first_time = 0;
+			sata_scr_read(link, SCR_STATUS, &gen_speed);
+			gen_speed = (gen_speed >> 4) & 0xf;
+			if (gen_speed == 1 || gen_speed == 2) {
+				/*
+				 * For Gen2/1 and start of the first time
+				 * COMRESET, re-program the PHY setting for
+				 * Gen2/1 speed and re-start the COMRESET
+				 * again.
+				 */
+				phy_set_speed(ctx->phy, ap->port_no,
+					      gen_speed == 2 ? 3000000000ULL :
+							       1500000000ULL);
+				xgene_ahci_phy_restart(link);
+				goto hardreset_retry;
+			}
+		}
+
+		/* Clear SER_DISPARITY/SER_10B_8B_ERR if set due to errata */
+		for (i = 0; i < 5; i++) {
+			/* Check if error bit set */
+			val = readl(port_mmio + PORT_SCR_ERR);
+			if (!(val & (SERR_DISPARITY | SERR_10B_8B_ERR)))
+				break;
+			/* Clear any error due to errata */
+			xgene_ahci_force_phy_rdy(ctx, ap->port_no, 1);
+			/* Reset the PHY Rx path */
+			phy_set_speed(ctx->phy, ap->port_no, 0);
+			xgene_ahci_force_phy_rdy(ctx, ap->port_no, 0);
+			/* Clear all errors */
+			val = readl(port_mmio + PORT_SCR_ERR);
+			writel(val, port_mmio + PORT_SCR_ERR);
+		}
+	}
+
+	/* clear all errors if any pending */
+	val = readl(port_mmio + PORT_SCR_ERR);
+	writel(val, port_mmio + PORT_SCR_ERR);
+
+	return rc;
+}
+
+static int xgene_ahci_hardreset(struct ata_link *link, unsigned int *class,
+				unsigned long deadline)
+{
+	struct ata_port *ap = link->ap;
+        struct ahci_host_priv *hpriv = ap->host->private_data;
+	void __iomem *port_mmio = ahci_port_base(ap);
+	bool online;
+	int rc;
+	int portcmd_saved;
+	u32 portclb_saved;
+	u32 portclbhi_saved;
+	u32 portrxfis_saved;
+	u32 portrxfishi_saved;
+
+	/* As hardreset resets these CSR, save it to restore later */
+	portcmd_saved = readl(port_mmio + PORT_CMD);
+	portclb_saved = readl(port_mmio + PORT_LST_ADDR);
+	portclbhi_saved = readl(port_mmio + PORT_LST_ADDR_HI);
+	portrxfis_saved = readl(port_mmio + PORT_FIS_ADDR);
+	portrxfishi_saved = readl(port_mmio + PORT_FIS_ADDR_HI);
+
+	ahci_stop_engine(ap);
+
+	rc = xgene_ahci_do_hardreset(link, deadline, &online);
+
+	/* As controller hardreset clears them, restore them */
+	writel(portcmd_saved, port_mmio + PORT_CMD);
+	writel(portclb_saved, port_mmio + PORT_LST_ADDR);
+	writel(portclbhi_saved, port_mmio + PORT_LST_ADDR_HI);
+	writel(portrxfis_saved, port_mmio + PORT_FIS_ADDR);
+	writel(portrxfishi_saved, port_mmio + PORT_FIS_ADDR_HI);
+
+	hpriv->start_engine(ap);
+
+	if (online)
+		*class = ahci_dev_classify(ap);
+
+	return rc;
+}
+
+static struct ata_port_operations xgene_ahci_ops = {
+	.inherits = &ahci_ops,
+	.hardreset = xgene_ahci_hardreset,
+	.read_id = xgene_ahci_read_id,
+};
+
+static const struct ata_port_info xgene_ahci_port_info = {
+	AHCI_HFLAGS(AHCI_HFLAG_NO_PMP | AHCI_HFLAG_YES_NCQ),
+	.flags = AHCI_FLAG_COMMON | ATA_FLAG_NCQ,
+	.pio_mask = ATA_PIO4,
+	.udma_mask = ATA_UDMA6,
+	.port_ops = &xgene_ahci_ops,
+};
+
+static int xgene_ahci_hw_init(struct ahci_host_priv *hpriv)
+{
+	struct xgene_ahci_context *ctx = pdata_to_ctx(hpriv->plat_data);
+	int i;
+	int rc;
+	u32 val;
+
+	/* Remove IP RAM out of shutdown */
+	rc = xgene_ahci_init_memram(ctx);
+	if (rc)
+		return rc;
+
+	for (i = 0; i < MAX_AHCI_CHN_PERCTR; i++)
+		xgene_ahci_set_phy_cfg(ctx, i);
+
+	/* AXI disable Mask */
+	writel(0xffffffff, hpriv->mmio + HOST_IRQ_STAT);
+	readl(hpriv->mmio + HOST_IRQ_STAT); /* Force a barrier */
+	writel(0, ctx->csr_base + INTSTATUSMASK);
+	readl(ctx->csr_base + INTSTATUSMASK); /* Force a barrier */
+	dev_dbg(ctx->dev, "top level interrupt mask 0x%X value 0x%08X\n",
+		INTSTATUSMASK, val);
+
+	writel(0x0, ctx->csr_base + ERRINTSTATUSMASK);
+	readl(ctx->csr_base + ERRINTSTATUSMASK); /* Force a barrier */
+	writel(0x0, ctx->csr_base + SATA_SHIM_OFFSET + INT_SLV_TMOMASK);
+	readl(ctx->csr_base + SATA_SHIM_OFFSET + INT_SLV_TMOMASK);
+
+	/* Enable AXI Interrupt */
+	writel(0xffffffff, ctx->csr_base + SLVRDERRATTRIBUTES);
+	writel(0xffffffff, ctx->csr_base + SLVWRERRATTRIBUTES);
+	writel(0xffffffff, ctx->csr_base + MSTRDERRATTRIBUTES);
+	writel(0xffffffff, ctx->csr_base + MSTWRERRATTRIBUTES);
+
+	/* Enable coherency */
+	val = readl(ctx->csr_base + BUSCTLREG);
+	val &= ~0x00000002;     /* Enable write coherency */
+	val &= ~0x00000001;     /* Enable read coherency */
+	writel(val, ctx->csr_base + BUSCTLREG);
+
+	val = readl(ctx->csr_base + IOFMSTRWAUX);
+	val |= (1 << 3);        /* Enable read coherency */
+	val |= (1 << 9);        /* Enable write coherency */
+	writel(val, ctx->csr_base + IOFMSTRWAUX);
+	val = readl(ctx->csr_base + IOFMSTRWAUX);
+	dev_dbg(ctx->dev, "coherency 0x%X value 0x%08X\n",
+		IOFMSTRWAUX, val);
+
+	return rc;
+}
+
+static int xgene_ahci_mux_select(struct xgene_ahci_context *ctx)
+{
+	void *mux_csr = ctx->csr_base + SATA_ENET_MUX_OFFSET;
+	u32 val;
+
+	val = readl(mux_csr + SATA_ENET_CONFIG_REG);
+	val &= ~CFG_SATA_ENET_SELECT_MASK;
+	writel(val, mux_csr + SATA_ENET_CONFIG_REG);
+	val = readl(mux_csr + SATA_ENET_CONFIG_REG);
+	return val & CFG_SATA_ENET_SELECT_MASK ? -1 : 0;
+}
+
+static int xgene_ahci_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct ahci_host_priv *hpriv;
+	struct xgene_ahci_context *hplat_data;
+	struct resource *res;
+	int rc;
+
+	hpriv = ahci_platform_get_resources(pdev);
+	if (IS_ERR(hpriv))
+		return PTR_ERR(hpriv);
+
+	hplat_data = devm_kzalloc(dev, sizeof(*hplat_data), GFP_KERNEL);
+	if (!hplat_data) {
+		dev_err(dev, "can't allocate host context\n");
+		return -ENOMEM;
+	}
+	hpriv->plat_data = hplat_data;
+	hplat_data->hpriv = hpriv;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+	if (!res) {
+		dev_err(dev, "no csr space\n");
+		return -EINVAL;
+	}
+
+	/*
+	 * Can't use devm_ioremap_resource due to overlapping region.
+	 * 0xYYYY.0000 - host core
+	 * 0xYYYY.7000 - Mux (if applicable)
+	 * 0xYYYY.A000 - PHY indirect access
+	 * 0xYYYY.C000 - Clock
+	 * 0xYYYY.D000 - RAM shutdown removal
+	 * As we map the entire region as one, it overlaps with the PHY driver.
+	 */
+	hplat_data->csr_base = devm_ioremap(dev, res->start,
+					    resource_size(res));
+	if (!hplat_data->csr_base) {
+		dev_err(dev, "can't map %pR\n", res);
+		return -ENOMEM;
+	}
+
+	dev_dbg(dev, "VAddr 0x%p Mmio VAddr 0x%p\n", hplat_data->csr_base,
+		hpriv->mmio);
+
+	/* Select ATA */
+	if (of_device_is_compatible(pdev->dev.of_node,
+		XGENE_AHCI_SGMII_DTS)) {
+		if (xgene_ahci_mux_select(hplat_data)) {
+			dev_err(dev, "SATA mux selection failed\n");
+			return -ENODEV;
+		}
+	}
+
+	rc = ahci_platform_enable_resources(hpriv);
+	if (rc)
+		goto put_resources;
+
+	/* HW requires toggle of the clock */
+	ahci_platform_disable_clks(hpriv);
+	rc = ahci_platform_enable_clks(hpriv);
+	if (rc)
+		goto put_resources;
+
+	/* Configure the PHY */
+	hplat_data->phy = devm_phy_get(dev, "sata-6g");
+	if (!hplat_data->phy) {
+		dev_err(dev, "no PHY available\n");
+		rc = -ENODEV;
+		goto disable_resources;
+	}
+
+	rc = phy_init(hplat_data->phy);
+	if (rc) {
+		dev_err(dev, "PHY initialize failed %d\n", rc);
+		goto disable_resources;
+	}
+
+	/* Configure the host controller */
+	xgene_ahci_hw_init(hpriv);
+
+	/* Setup DMA mask - 32 for 32-bit system and 64 for 64-bit system */
+	rc = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(8*sizeof(void *)));
+	if (rc) {
+		dev_err(dev, "Unable to set dma mask\n");
+		goto disable_resources;
+	}
+
+	rc = ahci_platform_init_host(pdev, hpriv, &xgene_ahci_port_info, 0, 0);
+	if (rc)
+		goto disable_resources;
+
+	dev_dbg(dev, "X-Gene SATA host controller initialized\n");
+	return 0;
+
+disable_resources:
+	ahci_platform_disable_resources(hpriv);
+put_resources:
+	ahci_platform_put_resources(hpriv);
+	return rc;
+}
+
+static const struct of_device_id xgene_ahci_of_match[] = {
+	{.compatible = XGENE_AHCI_SGMII_DTS,},
+	{.compatible = XGENE_AHCI_PCIE_DTS,},
+	{},
+};
+MODULE_DEVICE_TABLE(of, xgene_ahci_of_match);
+
+static struct platform_driver xgene_ahci_driver = {
+	.driver = {
+		.name = "xgene-ahci",
+		.owner = THIS_MODULE,
+		.of_match_table = xgene_ahci_of_match,
+	},
+	.probe = xgene_ahci_probe,
+};
+
+module_platform_driver(xgene_ahci_driver);
+
+MODULE_DESCRIPTION("APM X-Gene AHCI SATA driver");
+MODULE_AUTHOR("Loc Ho <lho@apm.com>");
+MODULE_LICENSE("GPL");
+MODULE_VERSION("0.4");
-- 
1.5.5

[PATCH v14 3/3] arm64: Add APM X-Gene SoC AHCI SATA host controller DTS entries

[Loc Ho]

Signed-off-by: Loc Ho <lho@apm.com>
Signed-off-by: Tuan Phan <tphan@apm.com>
Signed-off-by: Suman Tripathi <stripathi@apm.com>
---
 arch/arm64/boot/dts/apm-storm.dtsi |   75 ++++++++++++++++++++++++++++++++++++
 1 files changed, 75 insertions(+), 0 deletions(-)

diff --git a/arch/arm64/boot/dts/apm-storm.dtsi b/arch/arm64/boot/dts/apm-storm.dtsi
index c78ddcf..57b0770 100644
--- a/arch/arm64/boot/dts/apm-storm.dtsi
+++ b/arch/arm64/boot/dts/apm-storm.dtsi
@@ -221,6 +221,48 @@
 				enable-offset = <0x0>;
 				enable-mask = <0x06>;
 			};
+
+			sata01clk: sata01clk@1f21c000 {
+				compatible = "apm,xgene-device-clock";
+				#clock-cells = <1>;
+				clocks = <&socplldiv2 0>;
+				clock-names = "socplldiv2";
+				reg = <0x0 0x1f21c000 0x0 0x1000>;
+				reg-names = "csr-reg";
+				clock-output-names = "sata01clk";
+				csr-offset = <0x4>;
+				csr-mask = <0x05>;
+				enable-offset = <0x0>;
+				enable-mask = <0x39>;
+			};
+
+			sata23clk: sata23clk@1f22c000 {
+				compatible = "apm,xgene-device-clock";
+				#clock-cells = <1>;
+				clocks = <&socplldiv2 0>;
+				clock-names = "socplldiv2";
+				reg = <0x0 0x1f22c000 0x0 0x1000>;
+				reg-names = "csr-reg";
+				clock-output-names = "sata23clk";
+				csr-offset = <0x4>;
+				csr-mask = <0x05>;
+				enable-offset = <0x0>;
+				enable-mask = <0x39>;
+			};
+
+			sata45clk: sata45clk@1f23c000 {
+				compatible = "apm,xgene-device-clock";
+				#clock-cells = <1>;
+				clocks = <&socplldiv2 0>;
+				clock-names = "socplldiv2";
+				reg = <0x0 0x1f23c000 0x0 0x1000>;
+				reg-names = "csr-reg";
+				clock-output-names = "sata45clk";
+				csr-offset = <0x4>;
+				csr-mask = <0x05>;
+				enable-offset = <0x0>;
+				enable-mask = <0x39>;
+			};
 		};
 
 		serial0: serial@1c020000 {
@@ -262,5 +304,38 @@
 			apm,tx-boost-gain = <31 31 31 31 31 31>;
 			apm,tx-eye-tuning = <2 10 10 2 10 10>;
 		};
+
+		sata1: sata@1a000000 {
+			compatible = "apm,xgene-ahci-sgmii";
+			reg = <0x0 0x1a000000 0x0 0x1000>,
+			      <0x0 0x1f210000 0x0 0x10000>;
+			interrupts = <0x0 0x86 0x4>;
+			status = "disabled";
+			clocks = <&sata01clk 0>;
+			phys = <&phy1 0>;
+			phy-names = "sata-6g";
+		};
+
+		sata2: sata@1a400000 {
+			compatible = "apm,xgene-ahci-sgmii";
+			reg = <0x0 0x1a400000 0x0 0x1000>,
+			      <0x0 0x1f220000 0x0 0x10000>;
+			interrupts = <0x0 0x87 0x4>;
+			status = "ok";
+			clocks = <&sata23clk 0>;
+			phys = <&phy2 0>;
+			phy-names = "sata-6g";
+		};
+
+		sata3: sata@1a800000 {
+			compatible = "apm,xgene-ahci-pcie";
+			reg = <0x0 0x1a800000 0x0 0x1000>,
+			      <0x0 0x1f230000 0x0 0x10000>;
+			interrupts = <0x0 0x88 0x4>;
+			status = "ok";
+			clocks = <&sata45clk 0>;
+			phys = <&phy3 0>;
+			phy-names = "sata-6g";
+		};
 	};
 };
-- 
1.5.5

Re: [PATCH v14 2/3] ata: Add APM X-Gene SoC AHCI SATA host controller driver

[Bartlomiej Zolnierkiewicz]

Hi,

On Monday, February 24, 2014 10:28:06 PM Loc Ho wrote:
> This patch adds support for the APM X-Gene SoC AHCI SATA host controller
> driver. It requires the corresponding APM X-Gene SoC PHY driver.
> 
> Signed-off-by: Loc Ho <lho@apm.com>
> Signed-off-by: Tuan Phan <tphan@apm.com>
> Signed-off-by: Suman Tripathi <stripathi@apm.com>
> ---
>  drivers/ata/Kconfig      |    8 +
>  drivers/ata/Makefile     |    1 +
>  drivers/ata/ahci_xgene.c |  566 ++++++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 575 insertions(+), 0 deletions(-)
>  create mode 100644 drivers/ata/ahci_xgene.c
> 
> diff --git a/drivers/ata/Kconfig b/drivers/ata/Kconfig
> index cc67cc0..174e398 100644
> --- a/drivers/ata/Kconfig
> +++ b/drivers/ata/Kconfig
> @@ -115,6 +115,14 @@ config AHCI_SUNXI
>  
>  	  If unsure, say N.
>  
> +config AHCI_XGENE
> +	tristate "APM X-Gene 6.0Gbps AHCI SATA host controller support"
> +	depends on ARM64 || COMPILE_TEST
> +	select SATA_AHCI_PLATFORM

Other platform AHCI drivers depend on SATA_AHCI_PLATFORM and I think
that this driver should also do it for now.

> +	select PHY_XGENE
> +	help
> +	  This option enables support for APM X-Gene SoC SATA host controller.
> +
>  config SATA_FSL
>  	tristate "Freescale 3.0Gbps SATA support"
>  	depends on FSL_SOC
> diff --git a/drivers/ata/Makefile b/drivers/ata/Makefile
> index 246050b..72b423b 100644
> --- a/drivers/ata/Makefile
> +++ b/drivers/ata/Makefile
> @@ -12,6 +12,7 @@ obj-$(CONFIG_SATA_DWC)		+= sata_dwc_460ex.o
>  obj-$(CONFIG_SATA_HIGHBANK)	+= sata_highbank.o libahci.o
>  obj-$(CONFIG_AHCI_IMX)		+= ahci_imx.o
>  obj-$(CONFIG_AHCI_SUNXI)	+= ahci_sunxi.o
> +obj-$(CONFIG_AHCI_XGENE)	+= ahci_xgene.o
>  
>  # SFF w/ custom DMA
>  obj-$(CONFIG_PDC_ADMA)		+= pdc_adma.o
> diff --git a/drivers/ata/ahci_xgene.c b/drivers/ata/ahci_xgene.c
> new file mode 100644
> index 0000000..36ba229
> --- /dev/null
> +++ b/drivers/ata/ahci_xgene.c
> @@ -0,0 +1,566 @@
> +/*
> + * AppliedMicro X-Gene SoC SATA Host Controller Driver
> + *
> + * Copyright (c) 2014, Applied Micro Circuits Corporation
> + * Author: Loc Ho <lho@apm.com>
> + *         Tuan Phan <tphan@apm.com>
> + *         Suman Tripathi <stripathi@apm.com>
> + *
> + * This program is free software; you can redistribute  it and/or modify it
> + * under  the terms of  the GNU General  Public License as published by the
> + * Free Software Foundation;  either version 2 of the  License, or (at your
> + * option) any later version.
> + *
> + * This program is distributed in the hope that 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.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program.  If not, see <http://www.gnu.org/licenses/>.
> + *
> + */
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/ahci_platform.h>
> +#include <linux/of_address.h>
> +#include <linux/of_irq.h>
> +#include <linux/phy/phy.h>
> +#include "ahci.h"
> +
> +/* Controller who PHY shared with SGMII Ethernet PHY */
> +#define XGENE_AHCI_SGMII_DTS		"apm,xgene-ahci-sgmii"
> +
> +/* Controller who PHY (internal reference clock macro) shared with PCIe */
> +#define XGENE_AHCI_PCIE_DTS		"apm,xgene-ahci-pcie"
> +
> +/* Max # of disk per a controller */
> +#define MAX_AHCI_CHN_PERCTR		2
> +
> +#define SATA_ENET_MUX_OFFSET		0x00007000
> +#define SATA_DIAG_OFFSET		0x0000D000
> +#define SATA_GLB_OFFSET			0x0000D850
> +#define SATA_SHIM_OFFSET		0x0000E000
> +#define SATA_MASTER_OFFSET		0x0000F000
> +#define SATA_PORT0_OFFSET		0x00000100
> +#define SATA_PORT1_OFFSET		0x00000180
> +
> +/* MUX CSR */
> +#define SATA_ENET_CONFIG_REG		0x00000000
> +#define  CFG_SATA_ENET_SELECT_MASK	0x00000001
> +
> +/* SATA host controller CSR */
> +#define SLVRDERRATTRIBUTES		0x00000000
> +#define SLVWRERRATTRIBUTES		0x00000004
> +#define MSTRDERRATTRIBUTES		0x00000008
> +#define MSTWRERRATTRIBUTES		0x0000000c
> +#define BUSCTLREG			0x00000014
> +#define IOFMSTRWAUX			0x00000018
> +#define INTSTATUSMASK			0x0000002c
> +#define ERRINTSTATUS			0x00000030
> +#define ERRINTSTATUSMASK		0x00000034
> +
> +/* SATA host AHCI CSR */
> +#define PORTCFG				0x000000a4
> +#define  PORTADDR_SET(dst, src) \
> +		(((dst) & ~0x0000003f) | (((u32)(src)) & 0x0000003f))
> +#define PORTPHY1CFG		0x000000a8
> +#define PORTPHY1CFG_FRCPHYRDY_SET(dst, src) \
> +		(((dst) & ~0x00100000) | (((u32)(src) << 0x14) & 0x00100000))
> +#define PORTPHY2CFG			0x000000ac
> +#define PORTPHY3CFG			0x000000b0
> +#define PORTPHY4CFG			0x000000b4
> +#define PORTPHY5CFG			0x000000b8
> +#define SCTL0				0x0000012C
> +#define PORTPHY5CFG_RTCHG_SET(dst, src) \
> +		(((dst) & ~0xfff00000) | (((u32)(src) << 0x14) & 0xfff00000))
> +#define PORTAXICFG_EN_CONTEXT_SET(dst, src) \
> +		(((dst) & ~0x01000000) | (((u32)(src) << 0x18) & 0x01000000))
> +#define PORTAXICFG			0x000000bc
> +#define PORTAXICFG_OUTTRANS_SET(dst, src) \
> +		(((dst) & ~0x00f00000) | (((u32)(src) << 0x14) & 0x00f00000))
> +
> +/* SATA host controller slave CSR */
> +#define INT_SLV_TMOMASK			0x00000010
> +
> +/* SATA global diagnostic CSR */
> +#define CFG_MEM_RAM_SHUTDOWN		0x00000070
> +#define BLOCK_MEM_RDY			0x00000074
> +
> +#define pdata_to_ctx(x) container_of(x, struct xgene_ahci_context, plat_data)
> +
> +struct xgene_ahci_context {
> +	struct ahci_platform_data plat_data;

plat_data is used only to get to struct xgene_ahci_context instance
so it can be removed (especially since we want to remove struct
ahci_platform_data altogether in the long-term) and hpriv->plat_data
should be set to point to context instance itself.  Actually, this
seems to be the case already as hpriv->plat_data is set to hplat_data
(not to &hplat_data->plat_data) in xgene_ahci_probe() so I wonder how
does this driver work currently?

> +	struct ahci_host_priv *hpriv;
> +	struct device *dev;
> +	void __iomem *csr_base;		/* CSR base address of IP */
> +	struct phy *phy;
> +};
> +
> +static int xgene_ahci_init_memram(struct xgene_ahci_context *ctx)
> +{
> +	void __iomem *diagcsr = ctx->csr_base + SATA_DIAG_OFFSET;
> +
> +	dev_dbg(ctx->dev, "Release memory from shutdown\n");
> +	writel(0x0, diagcsr + CFG_MEM_RAM_SHUTDOWN);
> +	readl(diagcsr + CFG_MEM_RAM_SHUTDOWN); /* Force a barrier */
> +	msleep(1);	/* reset may take up to 1ms */
> +	if (readl(diagcsr + BLOCK_MEM_RDY) != 0xFFFFFFFF) {
> +		dev_err(ctx->dev, "failed to release memory from shutdown\n");
> +		return -ENODEV;
> +	}
> +	return 0;
> +}
> +
> +/**
> + * xgene_ahci_read_id - Read ID data from the specified device
> + * @dev: device
> + * @tf: proposed taskfile
> + * @id: data buffer
> + *
> + * This custom read ID function is required due to the fact that the HW
> + * does not support DEVSLP and the controller state machine may get stuck
> + * after processing the ID query command.
> + */
> +static unsigned int xgene_ahci_read_id(struct ata_device *dev,
> +				       struct ata_taskfile *tf, u16 *id)
> +{
> +	u32 err_mask;
> +	void __iomem *port_mmio = ahci_port_base(dev->link->ap);
> +
> +	err_mask = ata_do_dev_read_id(dev, tf, id);
> +	if (err_mask)
> +		return err_mask;
> +
> +	/*
> +	 * Mask reserved area. Bit78 spec of Link Power Management

Word78?

> +	 * bit15-8: reserved
> +	 * bit7: NCQ autosence
> +	 * bit6: Software settings preservation supported
> +	 * bit5: reserved
> +	 * bit4: In-order sata delivery supported
> +	 * bit3: DIPM requests supported
> +	 * bit2: DMA Setup FIS Auto-Activate optimization supported
> +	 * bit1: DMA Setup FIX non-Zero buffer offsets supported
> +	 * bit0: Reserved
> +	 *
> +	 * Clear reserved bit (DEVSLP bit) as we don't support DEVSLP
> +	 */
> +	id[78] &= 0x00FF;
> +
> +	/*
> +	 * Due to HW errata, restart the port if no other command active.
> +	 * Otherwise the controller may get stuck.
> +	 */
> +	if (!readl(port_mmio + PORT_CMD_ISSUE)) {
> +		writel(PORT_CMD_FIS_RX, port_mmio + PORT_CMD);
> +		readl(port_mmio + PORT_CMD);	/* Force a barrier */
> +		writel(PORT_CMD_FIS_RX | PORT_CMD_START, port_mmio + PORT_CMD);
> +		readl(port_mmio + PORT_CMD);	/* Force a barrier */
> +	}
> +	return 0;
> +}
> +
> +static void xgene_ahci_force_phy_rdy(struct xgene_ahci_context *ctx,
> +				     int channel, int force)

'force' can be made bool

> +{
> +	void __iomem *mmio = ctx->hpriv->mmio;
> +	u32 val;
> +
> +	val = readl(mmio + PORTCFG);
> +	val = PORTADDR_SET(val, channel == 0 ? 2 : 3);
> +	writel(val, mmio + PORTCFG);
> +	readl(mmio + PORTCFG);	/* Force a barrier */
> +	val = readl(mmio + PORTPHY1CFG);
> +	val = PORTPHY1CFG_FRCPHYRDY_SET(val, force);
> +	writel(val, mmio + PORTPHY1CFG);
> +}
> +
> +static void xgene_ahci_set_phy_cfg(struct xgene_ahci_context *ctx, int channel)
> +{
> +	void __iomem *mmio = ctx->hpriv->mmio;
> +	u32 val;
> +
> +	dev_dbg(ctx->dev, "port configure mmio 0x%p channel %d\n",
> +		mmio, channel);
> +	val = readl(mmio + PORTCFG);
> +	val = PORTADDR_SET(val, channel == 0 ? 2 : 3);
> +	writel(val, mmio + PORTCFG);
> +	readl(mmio + PORTCFG);  /* Force a barrier */
> +	/* Disable fix rate */
> +	writel(0x0001fffe, mmio + PORTPHY1CFG);
> +	readl(mmio + PORTPHY1CFG); /* Force a barrier */
> +	writel(0x5018461c, mmio + PORTPHY2CFG);
> +	readl(mmio + PORTPHY2CFG); /* Force a barrier */
> +	writel(0x1c081907, mmio + PORTPHY3CFG);
> +	readl(mmio + PORTPHY3CFG); /* Force a barrier */
> +	writel(0x1c080815, mmio + PORTPHY4CFG);
> +	readl(mmio + PORTPHY4CFG); /* Force a barrier */
> +	/* Set window negotiation */
> +	val = readl(mmio + PORTPHY5CFG);
> +	val = PORTPHY5CFG_RTCHG_SET(val, 0x300);
> +	writel(val, mmio + PORTPHY5CFG);
> +	readl(mmio + PORTPHY5CFG); /* Force a barrier */
> +	val = readl(mmio + PORTAXICFG);
> +	val = PORTAXICFG_EN_CONTEXT_SET(val, 0x1); /* Enable context mgmt */
> +	val = PORTAXICFG_OUTTRANS_SET(val, 0xe); /* Set outstanding */
> +	writel(val, mmio + PORTAXICFG);
> +	readl(mmio + PORTAXICFG); /* Force a barrier */
> +}
> +
> +static int xgene_ahci_phy_restart(struct ata_link *link)
> +{
> +	struct ata_port *port = link->ap;
> +	struct ahci_host_priv *hpriv = port->host->private_data;
> +	struct xgene_ahci_context *ctx = pdata_to_ctx(hpriv->plat_data);
> +
> +	xgene_ahci_force_phy_rdy(ctx, port->port_no, 1);
> +	xgene_ahci_force_phy_rdy(ctx, port->port_no, 0);
> +	return 0;

The return value is always 0 and is never checked by user of this
function (-> it should be made of void type).

> +}
> +
> +/**
> + * xgene_ahci_do_hardreset - Issue the actual COMRESET
> + * @link: link to reset
> + * @deadline: deadline jiffies for the operation
> + * @online: Return value to indicate if device online
> + *
> + * Due to the limitation of the hardware PHY, a difference set of setting is
> + * required for each supported disk speed - Gen3 (6.0Gbps), Gen2 (3.0Gbps),
> + * and Gen1 (1.5Gbps). Otherwise during long IO stress test, the PHY will
> + * report disparity error and etc. In addition, during COMRESET, there can
> + * be error reported in the register PORT_SCR_ERR. For SERR_DISPARITY and
> + * SERR_10B_8B_ERR, the PHY receiver line must be reseted. The following
> + * algorithm is followed to proper configure the hardware PHY during COMRESET:
> + *
> + * Alg Part 1:
> + * 1. Start the PHY at Gen3 speed (default setting)
> + * 2. Issue the COMRESET
> + * 3. If no link, go to Alg Part 3
> + * 4. If link up, determine if the negotiated speed matches the PHY
> + *    configured speed
> + * 5. If they matched, go to Alg Part 2
> + * 6. If they do not matched and first time, configure the PHY for the linked
> + *    up disk speed and repeat step 2
> + * 7. Go to Alg Part 2
> + *
> + * Alg Part 2:
> + * 1. On link up, if there are any SERR_DISPARITY and SERR_10B_8B_ERR error
> + *    reported in the register PORT_SCR_ERR, then reset the PHY receiver line
> + * 2. Go to Alg Part 3
> + *
> + * Alg Part 3:
> + * 1. Clear any pending from register PORT_SCR_ERR.
> + */
> +static int xgene_ahci_do_hardreset(struct ata_link *link,
> +				   unsigned long deadline, bool *online)
> +{
> +	const unsigned long *timing = sata_ehc_deb_timing(&link->eh_context);
> +	struct ata_port *ap = link->ap;
> +	struct ahci_host_priv *hpriv = ap->host->private_data;
> +	struct xgene_ahci_context *ctx = pdata_to_ctx(hpriv->plat_data);
> +	struct ahci_port_priv *pp = ap->private_data;
> +	u8 *d2h_fis = pp->rx_fis + RX_FIS_D2H_REG;
> +	void __iomem *port_mmio = ahci_port_base(ap);
> +	struct ata_taskfile tf;
> +	int first_time = 1;
> +	int rc;
> +	u32 val;
> +	int i;
> +
> +hardreset_retry:
> +	/* clear D2H reception area to properly wait for D2H FIS */
> +	ata_tf_init(link->device, &tf);
> +	tf.command = ATA_BUSY;
> +	ata_tf_to_fis(&tf, 0, 0, d2h_fis);
> +	rc = sata_link_hardreset(link, timing, deadline, online,
> +				 ahci_check_ready);
> +
> +	if (*online) {
> +		/* Check to ensure that the disk comes up in matching speed */
> +		if (first_time) {
> +			u32 gen_speed;
> +
> +			first_time = 0;
> +			sata_scr_read(link, SCR_STATUS, &gen_speed);
> +			gen_speed = (gen_speed >> 4) & 0xf;
> +			if (gen_speed == 1 || gen_speed == 2) {
> +				/*
> +				 * For Gen2/1 and start of the first time
> +				 * COMRESET, re-program the PHY setting for
> +				 * Gen2/1 speed and re-start the COMRESET
> +				 * again.
> +				 */
> +				phy_set_speed(ctx->phy, ap->port_no,
> +					      gen_speed == 2 ? 3000000000ULL :
> +							       1500000000ULL);
> +				xgene_ahci_phy_restart(link);
> +				goto hardreset_retry;
> +			}
> +		}
> +
> +		/* Clear SER_DISPARITY/SER_10B_8B_ERR if set due to errata */
> +		for (i = 0; i < 5; i++) {
> +			/* Check if error bit set */
> +			val = readl(port_mmio + PORT_SCR_ERR);
> +			if (!(val & (SERR_DISPARITY | SERR_10B_8B_ERR)))
> +				break;
> +			/* Clear any error due to errata */
> +			xgene_ahci_force_phy_rdy(ctx, ap->port_no, 1);
> +			/* Reset the PHY Rx path */
> +			phy_set_speed(ctx->phy, ap->port_no, 0);
> +			xgene_ahci_force_phy_rdy(ctx, ap->port_no, 0);
> +			/* Clear all errors */
> +			val = readl(port_mmio + PORT_SCR_ERR);
> +			writel(val, port_mmio + PORT_SCR_ERR);
> +		}
> +	}
> +
> +	/* clear all errors if any pending */
> +	val = readl(port_mmio + PORT_SCR_ERR);
> +	writel(val, port_mmio + PORT_SCR_ERR);
> +
> +	return rc;
> +}
> +
> +static int xgene_ahci_hardreset(struct ata_link *link, unsigned int *class,
> +				unsigned long deadline)
> +{
> +	struct ata_port *ap = link->ap;
> +        struct ahci_host_priv *hpriv = ap->host->private_data;
> +	void __iomem *port_mmio = ahci_port_base(ap);
> +	bool online;
> +	int rc;
> +	int portcmd_saved;

u32 portcmd_saved

> +	u32 portclb_saved;
> +	u32 portclbhi_saved;
> +	u32 portrxfis_saved;
> +	u32 portrxfishi_saved;
> +
> +	/* As hardreset resets these CSR, save it to restore later */
> +	portcmd_saved = readl(port_mmio + PORT_CMD);
> +	portclb_saved = readl(port_mmio + PORT_LST_ADDR);
> +	portclbhi_saved = readl(port_mmio + PORT_LST_ADDR_HI);
> +	portrxfis_saved = readl(port_mmio + PORT_FIS_ADDR);
> +	portrxfishi_saved = readl(port_mmio + PORT_FIS_ADDR_HI);
> +
> +	ahci_stop_engine(ap);
> +
> +	rc = xgene_ahci_do_hardreset(link, deadline, &online);
> +
> +	/* As controller hardreset clears them, restore them */
> +	writel(portcmd_saved, port_mmio + PORT_CMD);
> +	writel(portclb_saved, port_mmio + PORT_LST_ADDR);
> +	writel(portclbhi_saved, port_mmio + PORT_LST_ADDR_HI);
> +	writel(portrxfis_saved, port_mmio + PORT_FIS_ADDR);
> +	writel(portrxfishi_saved, port_mmio + PORT_FIS_ADDR_HI);
> +
> +	hpriv->start_engine(ap);
> +
> +	if (online)
> +		*class = ahci_dev_classify(ap);
> +
> +	return rc;
> +}
> +
> +static struct ata_port_operations xgene_ahci_ops = {
> +	.inherits = &ahci_ops,
> +	.hardreset = xgene_ahci_hardreset,
> +	.read_id = xgene_ahci_read_id,
> +};
> +
> +static const struct ata_port_info xgene_ahci_port_info = {
> +	AHCI_HFLAGS(AHCI_HFLAG_NO_PMP | AHCI_HFLAG_YES_NCQ),
> +	.flags = AHCI_FLAG_COMMON | ATA_FLAG_NCQ,
> +	.pio_mask = ATA_PIO4,
> +	.udma_mask = ATA_UDMA6,
> +	.port_ops = &xgene_ahci_ops,
> +};
> +
> +static int xgene_ahci_hw_init(struct ahci_host_priv *hpriv)
> +{
> +	struct xgene_ahci_context *ctx = pdata_to_ctx(hpriv->plat_data);
> +	int i;
> +	int rc;
> +	u32 val;
> +
> +	/* Remove IP RAM out of shutdown */
> +	rc = xgene_ahci_init_memram(ctx);
> +	if (rc)
> +		return rc;
> +
> +	for (i = 0; i < MAX_AHCI_CHN_PERCTR; i++)
> +		xgene_ahci_set_phy_cfg(ctx, i);
> +
> +	/* AXI disable Mask */
> +	writel(0xffffffff, hpriv->mmio + HOST_IRQ_STAT);
> +	readl(hpriv->mmio + HOST_IRQ_STAT); /* Force a barrier */
> +	writel(0, ctx->csr_base + INTSTATUSMASK);
> +	readl(ctx->csr_base + INTSTATUSMASK); /* Force a barrier */
> +	dev_dbg(ctx->dev, "top level interrupt mask 0x%X value 0x%08X\n",
> +		INTSTATUSMASK, val);
> +
> +	writel(0x0, ctx->csr_base + ERRINTSTATUSMASK);
> +	readl(ctx->csr_base + ERRINTSTATUSMASK); /* Force a barrier */
> +	writel(0x0, ctx->csr_base + SATA_SHIM_OFFSET + INT_SLV_TMOMASK);
> +	readl(ctx->csr_base + SATA_SHIM_OFFSET + INT_SLV_TMOMASK);
> +
> +	/* Enable AXI Interrupt */
> +	writel(0xffffffff, ctx->csr_base + SLVRDERRATTRIBUTES);
> +	writel(0xffffffff, ctx->csr_base + SLVWRERRATTRIBUTES);
> +	writel(0xffffffff, ctx->csr_base + MSTRDERRATTRIBUTES);
> +	writel(0xffffffff, ctx->csr_base + MSTWRERRATTRIBUTES);
> +
> +	/* Enable coherency */
> +	val = readl(ctx->csr_base + BUSCTLREG);
> +	val &= ~0x00000002;     /* Enable write coherency */
> +	val &= ~0x00000001;     /* Enable read coherency */
> +	writel(val, ctx->csr_base + BUSCTLREG);
> +
> +	val = readl(ctx->csr_base + IOFMSTRWAUX);
> +	val |= (1 << 3);        /* Enable read coherency */
> +	val |= (1 << 9);        /* Enable write coherency */
> +	writel(val, ctx->csr_base + IOFMSTRWAUX);
> +	val = readl(ctx->csr_base + IOFMSTRWAUX);
> +	dev_dbg(ctx->dev, "coherency 0x%X value 0x%08X\n",
> +		IOFMSTRWAUX, val);
> +
> +	return rc;
> +}
> +
> +static int xgene_ahci_mux_select(struct xgene_ahci_context *ctx)
> +{
> +	void *mux_csr = ctx->csr_base + SATA_ENET_MUX_OFFSET;
> +	u32 val;
> +
> +	val = readl(mux_csr + SATA_ENET_CONFIG_REG);
> +	val &= ~CFG_SATA_ENET_SELECT_MASK;
> +	writel(val, mux_csr + SATA_ENET_CONFIG_REG);
> +	val = readl(mux_csr + SATA_ENET_CONFIG_REG);
> +	return val & CFG_SATA_ENET_SELECT_MASK ? -1 : 0;
> +}
> +
> +static int xgene_ahci_probe(struct platform_device *pdev)
> +{
> +	struct device *dev = &pdev->dev;
> +	struct ahci_host_priv *hpriv;
> +	struct xgene_ahci_context *hplat_data;

'hplat_data' is a very confusing name for this variable (all other
functions are just using 'ctx' so it would be best to also use 'ctx'
here).

> +	struct resource *res;
> +	int rc;
> +
> +	hpriv = ahci_platform_get_resources(pdev);
> +	if (IS_ERR(hpriv))
> +		return PTR_ERR(hpriv);
> +
> +	hplat_data = devm_kzalloc(dev, sizeof(*hplat_data), GFP_KERNEL);
> +	if (!hplat_data) {
> +		dev_err(dev, "can't allocate host context\n");
> +		return -ENOMEM;
> +	}
> +	hpriv->plat_data = hplat_data;
> +	hplat_data->hpriv = hpriv;
> +
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
> +	if (!res) {
> +		dev_err(dev, "no csr space\n");
> +		return -EINVAL;
> +	}
> +
> +	/*
> +	 * Can't use devm_ioremap_resource due to overlapping region.
> +	 * 0xYYYY.0000 - host core
> +	 * 0xYYYY.7000 - Mux (if applicable)
> +	 * 0xYYYY.A000 - PHY indirect access
> +	 * 0xYYYY.C000 - Clock
> +	 * 0xYYYY.D000 - RAM shutdown removal
> +	 * As we map the entire region as one, it overlaps with the PHY driver.
> +	 */
> +	hplat_data->csr_base = devm_ioremap(dev, res->start,
> +					    resource_size(res));
> +	if (!hplat_data->csr_base) {
> +		dev_err(dev, "can't map %pR\n", res);
> +		return -ENOMEM;
> +	}
> +
> +	dev_dbg(dev, "VAddr 0x%p Mmio VAddr 0x%p\n", hplat_data->csr_base,
> +		hpriv->mmio);
> +
> +	/* Select ATA */
> +	if (of_device_is_compatible(pdev->dev.of_node,
> +		XGENE_AHCI_SGMII_DTS)) {
> +		if (xgene_ahci_mux_select(hplat_data)) {
> +			dev_err(dev, "SATA mux selection failed\n");
> +			return -ENODEV;
> +		}
> +	}
> +
> +	rc = ahci_platform_enable_resources(hpriv);
> +	if (rc)
> +		goto put_resources;
> +
> +	/* HW requires toggle of the clock */
> +	ahci_platform_disable_clks(hpriv);
> +	rc = ahci_platform_enable_clks(hpriv);

Why is this needed (extra clocks disable->enable sequence)?

> +	if (rc)
> +		goto put_resources;
> +
> +	/* Configure the PHY */
> +	hplat_data->phy = devm_phy_get(dev, "sata-6g");

Why the standard "sata-phy" support in 
ahci_platform_[get,enable,disable]_resources()
is not used instead?

> +	if (!hplat_data->phy) {
> +		dev_err(dev, "no PHY available\n");
> +		rc = -ENODEV;
> +		goto disable_resources;
> +	}
> +
> +	rc = phy_init(hplat_data->phy);
> +	if (rc) {
> +		dev_err(dev, "PHY initialize failed %d\n", rc);
> +		goto disable_resources;
> +	}
> +
> +	/* Configure the host controller */
> +	xgene_ahci_hw_init(hpriv);
> +
> +	/* Setup DMA mask - 32 for 32-bit system and 64 for 64-bit system */
> +	rc = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(8*sizeof(void *)));
> +	if (rc) {

phy_exit() is missing

> +		dev_err(dev, "Unable to set dma mask\n");
> +		goto disable_resources;
> +	}
> +
> +	rc = ahci_platform_init_host(pdev, hpriv, &xgene_ahci_port_info, 0, 0);
> +	if (rc)

ditto

> +		goto disable_resources;
> +
> +	dev_dbg(dev, "X-Gene SATA host controller initialized\n");
> +	return 0;
> +
> +disable_resources:
> +	ahci_platform_disable_resources(hpriv);
> +put_resources:
> +	ahci_platform_put_resources(hpriv);

This is internal to ahci-platform.c in the current libata tree
(-> this driver won't build currently) and there is no need to
call it now.

> +	return rc;
> +}
> +
> +static const struct of_device_id xgene_ahci_of_match[] = {
> +	{.compatible = XGENE_AHCI_SGMII_DTS,},
> +	{.compatible = XGENE_AHCI_PCIE_DTS,},
> +	{},
> +};
> +MODULE_DEVICE_TABLE(of, xgene_ahci_of_match);
> +
> +static struct platform_driver xgene_ahci_driver = {
> +	.driver = {
> +		.name = "xgene-ahci",
> +		.owner = THIS_MODULE,
> +		.of_match_table = xgene_ahci_of_match,

Power Management support is missing altogether, please see ahci_imx.c
and ahci_sunxi.c on how it should be implemented.

> +	},
> +	.probe = xgene_ahci_probe,

.remove method is also needed, usually it is handled by adding custom
->host_stop method and using ata_platform_remove_one() as .remove
method (please refer to ahci_imx.c for examples).

> +};
> +
> +module_platform_driver(xgene_ahci_driver);
> +
> +MODULE_DESCRIPTION("APM X-Gene AHCI SATA driver");
> +MODULE_AUTHOR("Loc Ho <lho@apm.com>");
> +MODULE_LICENSE("GPL");
> +MODULE_VERSION("0.4");

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics

Re: [PATCH v14 2/3] ata: Add APM X-Gene SoC AHCI SATA host controller driver

[Loc Ho]

Hi,

>> +#define pdata_to_ctx(x) container_of(x, struct xgene_ahci_context, plat_data)
>> +
>> +struct xgene_ahci_context {
>> +     struct ahci_platform_data plat_data;
>
> plat_data is used only to get to struct xgene_ahci_context instance
> so it can be removed (especially since we want to remove struct
> ahci_platform_data altogether in the long-term) and hpriv->plat_data
> should be set to point to context instance itself.  Actually, this
> seems to be the case already as hpriv->plat_data is set to hplat_data
> (not to &hplat_data->plat_data) in xgene_ahci_probe() so I wonder how
> does this driver work currently?

I will remove the plat_data. .

>> +/**
>> + * xgene_ahci_read_id - Read ID data from the specified device
>> + * @dev: device
>> + * @tf: proposed taskfile
>> + * @id: data buffer
>> + *
>> + * This custom read ID function is required due to the fact that the HW
>> + * does not support DEVSLP and the controller state machine may get stuck
>> + * after processing the ID query command.
>> + */
>> +static unsigned int xgene_ahci_read_id(struct ata_device *dev,
>> +                                    struct ata_taskfile *tf, u16 *id)
>> +{
>> +     u32 err_mask;
>> +     void __iomem *port_mmio = ahci_port_base(dev->link->ap);
>> +
>> +     err_mask = ata_do_dev_read_id(dev, tf, id);
>> +     if (err_mask)
>> +             return err_mask;
>> +
>> +     /*
>> +      * Mask reserved area. Bit78 spec of Link Power Management
>
> Word78?

Yes...

>
>> +      * bit15-8: reserved
>> +      * bit7: NCQ autosence
>> +      * bit6: Software settings preservation supported
>> +      * bit5: reserved
>> +      * bit4: In-order sata delivery supported
>> +      * bit3: DIPM requests supported
>> +      * bit2: DMA Setup FIS Auto-Activate optimization supported
>> +      * bit1: DMA Setup FIX non-Zero buffer offsets supported
>> +      * bit0: Reserved
>> +      *
>> +      * Clear reserved bit (DEVSLP bit) as we don't support DEVSLP
>> +      */
>> +     id[78] &= 0x00FF;

I will also fix this up by bit mask off.

>> +
>> +     /* HW requires toggle of the clock */
>> +     ahci_platform_disable_clks(hpriv);
>> +     rc = ahci_platform_enable_clks(hpriv);
>
> Why is this needed (extra clocks disable->enable sequence)?

This is an HW errata with the clock. If I don't give the clock an full
cycle, it doesn't work.

-Loc