highbank: add custom ahci_link_up function

The Calxeda highbank SOC needs a custom sequence to bring up SATA links,
so override ahci_link_up with custom function to handle combophy setup.

Signed-off-by: Mark Langsdorf <mark.langsdorf@gmail.com>
Signed-off-by: Richard Gibbs
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Andre Przywara <osp@andrep.de>

board/highbank/Makefile

@@ -5,4 +5,4 @@
 # SPDX-License-Identifier:	GPL-2.0+
 #
 
-obj-y	:= highbank.o
+obj-y	:= highbank.o ahci.o

board/highbank/ahci.c

@@ -0,0 +1,218 @@
+/*
+ * Copyright 2012 Calxeda, Inc.
+ *
+ * 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 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 <common.h>
+#include <ahci.h>
+#include <asm/io.h>
+
+#define CPHY_MAP(dev, addr) ((((dev) & 0x1f) << 7) | (((addr) >> 9) & 0x7f))
+#define CPHY_ADDR(base, dev, addr) ((base) | (((addr) & 0x1ff) << 2))
+#define CPHY_BASE			0xfff58000
+#define CPHY_WIDTH			0x1000
+#define CPHY_DTE_XS			5
+#define CPHY_MII			31
+#define SERDES_CR_CTL			0x80a0
+#define SERDES_CR_ADDR			0x80a1
+#define SERDES_CR_DATA			0x80a2
+#define CR_BUSY				0x0001
+#define CR_START			0x0001
+#define CR_WR_RDN			0x0002
+#define CPHY_TX_INPUT_STS		0x2001
+#define CPHY_RX_INPUT_STS		0x2002
+#define CPHY_SATA_TX_OVERRIDE_BIT	0x8000
+#define CPHY_SATA_RX_OVERRIDE_BIT	0x4000
+#define CPHY_TX_INPUT_OVERRIDE		0x2004
+#define CPHY_RX_INPUT_OVERRIDE		0x2005
+#define SPHY_LANE			0x100
+#define SPHY_HALF_RATE			0x0001
+#define CPHY_SATA_DPLL_MODE		0x0700
+#define CPHY_SATA_DPLL_SHIFT		8
+#define CPHY_SATA_TX_ATTEN		0x1c00
+#define CPHY_SATA_TX_ATTEN_SHIFT	10
+
+#define HB_SREG_SATA_ATTEN		0xfff3cf24
+
+#define SATA_PORT_BASE			0xffe08000
+#define SATA_VERSIONR			0xf8
+#define SATA_HB_VERSION			0x3332302a
+
+static u32 __combo_phy_reg_read(u8 phy, u8 dev, u32 addr)
+{
+	u32 data;
+	writel(CPHY_MAP(dev, addr), CPHY_BASE + 0x800 + CPHY_WIDTH * phy);
+	data = readl(CPHY_ADDR(CPHY_BASE + CPHY_WIDTH * phy, dev, addr));
+	return data;
+}
+
+static void __combo_phy_reg_write(u8 phy, u8 dev, u32 addr, u32 data)
+{
+	writel(CPHY_MAP(dev, addr), CPHY_BASE + 0x800 + CPHY_WIDTH * phy);
+	writel(data, CPHY_ADDR(CPHY_BASE + CPHY_WIDTH * phy, dev, addr));
+}
+
+static u32 combo_phy_read(u8 phy, u32 addr)
+{
+	u8 dev = CPHY_DTE_XS;
+	if (phy == 5)
+		dev = CPHY_MII;
+	while (__combo_phy_reg_read(phy, dev, SERDES_CR_CTL) & CR_BUSY)
+		udelay(5);
+	__combo_phy_reg_write(phy, dev, SERDES_CR_ADDR, addr);
+	__combo_phy_reg_write(phy, dev, SERDES_CR_CTL, CR_START);
+	while (__combo_phy_reg_read(phy, dev, SERDES_CR_CTL) & CR_BUSY)
+		udelay(5);
+	return __combo_phy_reg_read(phy, dev, SERDES_CR_DATA);
+}
+
+static void combo_phy_write(u8 phy, u32 addr, u32 data)
+{
+	u8 dev = CPHY_DTE_XS;
+	if (phy == 5)
+		dev = CPHY_MII;
+	while (__combo_phy_reg_read(phy, dev, SERDES_CR_CTL) & CR_BUSY)
+		udelay(5);
+	__combo_phy_reg_write(phy, dev, SERDES_CR_ADDR, addr);
+	__combo_phy_reg_write(phy, dev, SERDES_CR_DATA, data);
+	__combo_phy_reg_write(phy, dev, SERDES_CR_CTL, CR_WR_RDN | CR_START);
+}
+
+static void cphy_spread_spectrum_override(u8 phy, u8 lane, u32 val)
+{
+	u32 tmp;
+	tmp = combo_phy_read(phy, CPHY_RX_INPUT_STS + lane * SPHY_LANE);
+	tmp &= ~CPHY_SATA_RX_OVERRIDE_BIT;
+	combo_phy_write(phy, CPHY_RX_INPUT_OVERRIDE + lane * SPHY_LANE, tmp);
+
+	tmp |= CPHY_SATA_RX_OVERRIDE_BIT;
+	combo_phy_write(phy, CPHY_RX_INPUT_OVERRIDE + lane * SPHY_LANE, tmp);
+
+	tmp &= ~CPHY_SATA_DPLL_MODE;
+	tmp |= (val << CPHY_SATA_DPLL_SHIFT) & CPHY_SATA_DPLL_MODE;
+	combo_phy_write(phy, CPHY_RX_INPUT_OVERRIDE + lane * SPHY_LANE, tmp);
+}
+
+static void cphy_tx_attenuation_override(u8 phy, u8 lane)
+{
+	u32 val;
+	u32 tmp;
+	u8  shift;
+
+	shift = ((phy == 5) ? 4 : lane) * 4;
+
+	val = (readl(HB_SREG_SATA_ATTEN) >> shift) & 0xf;
+
+	if (val & 0x8)
+		return;
+
+	tmp = combo_phy_read(phy, CPHY_TX_INPUT_STS + lane * SPHY_LANE);
+	tmp &= ~CPHY_SATA_TX_OVERRIDE_BIT;
+	combo_phy_write(phy, CPHY_TX_INPUT_OVERRIDE + lane * SPHY_LANE, tmp);
+
+	tmp |= CPHY_SATA_TX_OVERRIDE_BIT;
+	combo_phy_write(phy, CPHY_TX_INPUT_OVERRIDE + lane * SPHY_LANE, tmp);
+
+	tmp |= (val << CPHY_SATA_TX_ATTEN_SHIFT) & CPHY_SATA_TX_ATTEN;
+	combo_phy_write(phy, CPHY_TX_INPUT_OVERRIDE + lane * SPHY_LANE, tmp);
+}
+
+static void cphy_disable_port_overrides(u8 port)
+{
+	u32 tmp;
+	u8 lane = 0, phy = 0;
+
+	if (port == 0)
+		phy = 5;
+	else if (port < 5)
+		lane = port - 1;
+	else
+		return;
+	tmp = combo_phy_read(phy, CPHY_RX_INPUT_STS + lane * SPHY_LANE);
+	tmp &= ~CPHY_SATA_RX_OVERRIDE_BIT;
+	combo_phy_write(phy, CPHY_RX_INPUT_OVERRIDE + lane * SPHY_LANE, tmp);
+
+	tmp = combo_phy_read(phy, CPHY_TX_INPUT_OVERRIDE + lane * SPHY_LANE);
+	tmp &= ~CPHY_SATA_TX_OVERRIDE_BIT;
+	combo_phy_write(phy, CPHY_TX_INPUT_OVERRIDE + lane * SPHY_LANE, tmp);
+}
+
+void cphy_disable_overrides(void)
+{
+	int i;
+	u32 port_map;
+
+	port_map = readl(0xffe08000 + HOST_PORTS_IMPL);
+	for (i = 0; i < 5; i++) {
+		if (port_map & (1 << i))
+			cphy_disable_port_overrides(i);
+	}
+}
+
+static void cphy_override_lane(u8 port)
+{
+	u32 tmp, k = 0;
+	u8 lane = 0, phy = 0;
+
+	if (port == 0)
+		phy = 5;
+	else if (port < 5)
+		lane = port - 1;
+	else
+		return;
+
+	do {
+		tmp = combo_phy_read(0, CPHY_RX_INPUT_STS +
+					lane * SPHY_LANE);
+	} while ((tmp & SPHY_HALF_RATE) && (k++ < 1000));
+	cphy_spread_spectrum_override(phy, lane, 3);
+	cphy_tx_attenuation_override(phy, lane);
+}
+
+#define WAIT_MS_LINKUP	4
+
+int ahci_link_up(struct ahci_probe_ent *probe_ent, int port)
+{
+	u32 tmp;
+	int j = 0;
+	u8 *port_mmio = (u8 *)probe_ent->port[port].port_mmio;
+	u32 is_highbank = readl(SATA_PORT_BASE + SATA_VERSIONR) ==
+				SATA_HB_VERSION ? 1 : 0;
+
+	/* Bring up SATA link.
+	 * SATA link bringup time is usually less than 1 ms; only very
+	 * rarely has it taken between 1-2 ms. Never seen it above 2 ms.
+	 */
+	while (j < WAIT_MS_LINKUP) {
+		if (is_highbank && (j == 0)) {
+			cphy_disable_port_overrides(port);
+			writel(0x301, port_mmio + PORT_SCR_CTL);
+			udelay(1000);
+			writel(0x300, port_mmio + PORT_SCR_CTL);
+			udelay(1000);
+			cphy_override_lane(port);
+		}
+
+		tmp = readl(port_mmio + PORT_SCR_STAT);
+		if ((tmp & 0xf) == 0x3)
+			return 0;
+		udelay(1000);
+		j++;
+
+		if ((j == WAIT_MS_LINKUP) && (tmp & 0xf))
+			j = 0;	/* retry phy reset */
+	}
+	return 1;
+}

board/highbank/highbank.c

@@ -35,6 +35,8 @@
 
 DECLARE_GLOBAL_DATA_PTR;
 
+void cphy_disable_overrides(void);
+
 /*
  * Miscellaneous platform dependent initialisations
  */
@@ -62,6 +64,7 @@ void scsi_init(void)
 {
 	u32 reg = readl(HB_SREG_A9_PWRDOM_STAT);
 
+	cphy_disable_overrides();
 	if (reg & PWRDOM_STAT_SATA) {
 		ahci_init((void __iomem *)HB_AHCI_BASE);
 		scsi_scan(1);
@@ -136,3 +139,12 @@ void reset_cpu(ulong addr)
 
 	wfi();
 }
+
+/*
+ * turn off the override before transferring control to Linux, since Linux
+ * may not support spread spectrum.
+ */
+void arch_preboot_os(void)
+{
+	cphy_disable_overrides();
+}