kernel: b53: add Register Access Bridge Registers (SRAB) interface

The SRAB interface is used on BCM4707 and BCM5301X SoCs.

Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>

SVN-Revision: 38198

3 files changed, 388 insertions, 0 deletions

diff --git a/target/linux/generic/files/drivers/net/phy/b53/Kconfig b/target/linux/generic/files/drivers/net/phy/b53/Kconfig
index 3b514fb622..67e053ea0f 100644
--- a/target/linux/generic/files/drivers/net/phy/b53/Kconfig
+++ b/target/linux/generic/files/drivers/net/phy/b53/Kconfig
@@ -26,5 +26,12 @@ config B53_MMAP_DRIVER
 	  Select to enable support for memory-mapped switches like the BCM63XX
 	  integrated switches.
 
+config B53_SRAB_DRIVER
+	tristate "B53 SRAB connected switch driver"
+	depends on B53
+	help
+	  Select to enable support for memory-mapped Switch Register Access
+	  Bridge Registers (SRAB) like it is found on the BCM53010
+
 config B53_PHY_FIXUP
 	bool
diff --git a/target/linux/generic/files/drivers/net/phy/b53/Makefile b/target/linux/generic/files/drivers/net/phy/b53/Makefile
index 146196e088..7cc39c7628 100644
--- a/target/linux/generic/files/drivers/net/phy/b53/Makefile
+++ b/target/linux/generic/files/drivers/net/phy/b53/Makefile
@@ -3,6 +3,7 @@ obj-$(CONFIG_B53)		+= b53_common.o
 obj-$(CONFIG_B53_PHY_FIXUP)	+= b53_phy_fixup.o
 
 obj-$(CONFIG_B53_MMAP_DRIVER)	+= b53_mmap.o
+obj-$(CONFIG_B53_SRAB_DRIVER)	+= b53_srab.o
 obj-$(CONFIG_B53_PHY_DRIVER)	+= b53_mdio.o
 obj-$(CONFIG_B53_SPI_DRIVER)	+= b53_spi.o
 
diff --git a/target/linux/generic/files/drivers/net/phy/b53/b53_srab.c b/target/linux/generic/files/drivers/net/phy/b53/b53_srab.c
new file mode 100644
index 0000000000..f0743b7017
--- /dev/null
+++ b/target/linux/generic/files/drivers/net/phy/b53/b53_srab.c
@@ -0,0 +1,380 @@
+/*
+ * B53 register access through Switch Register Access Bridge Registers
+ *
+ * Copyright (C) 2013 Hauke Mehrtens <hauke@hauke-m.de>
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/platform_data/b53.h>
+
+#include "b53_priv.h"
+
+/* command and status register of the SRAB */
+#define B53_SRAB_CMDSTAT		0x2c
+#define  B53_SRAB_CMDSTAT_RST		BIT(2)
+#define  B53_SRAB_CMDSTAT_WRITE		BIT(1)
+#define  B53_SRAB_CMDSTAT_GORDYN	BIT(0)
+#define  B53_SRAB_CMDSTAT_PAGE		24
+#define  B53_SRAB_CMDSTAT_REG		16
+
+/* high order word of write data to switch registe */
+#define B53_SRAB_WD_H			0x30
+
+/* low order word of write data to switch registe */
+#define B53_SRAB_WD_L			0x34
+
+/* high order word of read data from switch register */
+#define B53_SRAB_RD_H			0x38
+
+/* low order word of read data from switch register */
+#define B53_SRAB_RD_L			0x3c
+
+/* command and status register of the SRAB */
+#define B53_SRAB_CTRLS			0x40
+#define  B53_SRAB_CTRLS_RCAREQ		BIT(3)
+#define  B53_SRAB_CTRLS_RCAGNT		BIT(4)
+#define  B53_SRAB_CTRLS_SW_INIT_DONE	BIT(6)
+
+/* the register captures interrupt pulses from the switch */
+#define B53_SRAB_INTR			0x44
+
+static int b53_srab_request_grant(struct b53_device *dev)
+{
+	u8 __iomem *regs = dev->priv;
+	u32 ctrls;
+	int i;
+
+	ctrls = readl(regs + B53_SRAB_CTRLS);
+	ctrls |= B53_SRAB_CTRLS_RCAREQ;
+	writel(ctrls, regs + B53_SRAB_CTRLS);
+
+	for (i = 0; i < 20; i++) {
+		ctrls = readl(regs + B53_SRAB_CTRLS);
+		if (ctrls & B53_SRAB_CTRLS_RCAGNT)
+			break;
+		usleep_range(10, 100);
+	}
+	if (WARN_ON(i == 5))
+		return -EIO;
+
+	return 0;
+}
+
+static void b53_srab_release_grant(struct b53_device *dev)
+{
+	u8 __iomem *regs = dev->priv;
+	u32 ctrls;
+
+	ctrls = readl(regs + B53_SRAB_CTRLS);
+	ctrls &= ~B53_SRAB_CTRLS_RCAREQ;
+	writel(ctrls, regs + B53_SRAB_CTRLS);
+}
+
+static int b53_srab_op(struct b53_device *dev, u8 page, u8 reg, u32 op)
+{
+	int i;
+	u32 cmdstat;
+	u8 __iomem *regs = dev->priv;
+
+	/* set register address */
+	cmdstat = (page << B53_SRAB_CMDSTAT_PAGE) |
+		  (reg << B53_SRAB_CMDSTAT_REG) |
+		  B53_SRAB_CMDSTAT_GORDYN |
+		  op;
+	writel(cmdstat, regs + B53_SRAB_CMDSTAT);
+	
+	/* check if operation completed */
+	for (i = 0; i < 5; ++i) {
+		cmdstat = readl(regs + B53_SRAB_CMDSTAT);
+		if (!(cmdstat & B53_SRAB_CMDSTAT_GORDYN))
+			break;
+		usleep_range(10, 100);
+	}
+
+	if (WARN_ON(i == 5))
+		return -EIO;
+
+	return 0;
+}
+
+static int b53_srab_read8(struct b53_device *dev, u8 page, u8 reg, u8 *val)
+{
+	u8 __iomem *regs = dev->priv;
+	int ret = 0;
+
+	ret = b53_srab_request_grant(dev);
+	if (ret)
+		goto err;
+
+	ret = b53_srab_op(dev, page, reg, 0);
+	if (ret)
+		goto err;
+
+	*val = readl(regs + B53_SRAB_RD_L) & 0xff;
+
+err:
+	b53_srab_release_grant(dev);
+
+	return ret;
+}
+
+static int b53_srab_read16(struct b53_device *dev, u8 page, u8 reg, u16 *val)
+{
+	u8 __iomem *regs = dev->priv;
+	int ret = 0;
+
+	ret = b53_srab_request_grant(dev);
+	if (ret)
+		goto err;
+
+	ret = b53_srab_op(dev, page, reg, 0);
+	if (ret)
+		goto err;
+
+	*val = readl(regs + B53_SRAB_RD_L) & 0xffff;
+
+err:
+	b53_srab_release_grant(dev);
+
+	return ret;
+}
+
+static int b53_srab_read32(struct b53_device *dev, u8 page, u8 reg, u32 *val)
+{
+	u8 __iomem *regs = dev->priv;
+	int ret = 0;
+
+	ret = b53_srab_request_grant(dev);
+	if (ret)
+		goto err;
+
+	ret = b53_srab_op(dev, page, reg, 0);
+	if (ret)
+		goto err;
+
+	*val = readl(regs + B53_SRAB_RD_L);
+
+err:
+	b53_srab_release_grant(dev);
+
+	return ret;
+}
+
+static int b53_srab_read48(struct b53_device *dev, u8 page, u8 reg, u64 *val)
+{
+	u8 __iomem *regs = dev->priv;
+	int ret = 0;
+
+	ret = b53_srab_request_grant(dev);
+	if (ret)
+		goto err;
+
+	ret = b53_srab_op(dev, page, reg, 0);
+	if (ret)
+		goto err;
+
+	*val = readl(regs + B53_SRAB_RD_L);
+	*val += ((u64)readl(regs + B53_SRAB_RD_H) & 0xffff) << 32;
+	
+err:
+	b53_srab_release_grant(dev);
+
+	return ret;
+}
+
+static int b53_srab_read64(struct b53_device *dev, u8 page, u8 reg, u64 *val)
+{
+	u8 __iomem *regs = dev->priv;
+	int ret = 0;
+
+	ret = b53_srab_request_grant(dev);
+	if (ret)
+		goto err;
+
+	ret = b53_srab_op(dev, page, reg, 0);
+	if (ret)
+		goto err;
+
+	*val = readl(regs + B53_SRAB_RD_L);
+	*val += (u64)readl(regs + B53_SRAB_RD_H) << 32;
+
+err:
+	b53_srab_release_grant(dev);
+
+	return ret;
+}
+
+static int b53_srab_write8(struct b53_device *dev, u8 page, u8 reg, u8 value)
+{
+	u8 __iomem *regs = dev->priv;
+	int ret = 0;
+
+	ret = b53_srab_request_grant(dev);
+	if (ret)
+		goto err;
+
+	writel(value, regs + B53_SRAB_WD_L);
+
+	ret = b53_srab_op(dev, page, reg, B53_SRAB_CMDSTAT_WRITE);
+
+err:
+	b53_srab_release_grant(dev);
+
+	return ret;
+}
+
+static int b53_srab_write16(struct b53_device *dev, u8 page, u8 reg,
+			     u16 value)
+{
+	u8 __iomem *regs = dev->priv;
+	int ret = 0;
+
+	ret = b53_srab_request_grant(dev);
+	if (ret)
+		goto err;
+
+	writel(value, regs + B53_SRAB_WD_L);
+
+	ret = b53_srab_op(dev, page, reg, B53_SRAB_CMDSTAT_WRITE);
+
+err:
+	b53_srab_release_grant(dev);
+
+	return ret;
+}
+
+static int b53_srab_write32(struct b53_device *dev, u8 page, u8 reg,
+				    u32 value)
+{
+	u8 __iomem *regs = dev->priv;
+	int ret = 0;
+
+	ret = b53_srab_request_grant(dev);
+	if (ret)
+		goto err;
+
+	writel(value, regs + B53_SRAB_WD_L);
+
+	ret = b53_srab_op(dev, page, reg, B53_SRAB_CMDSTAT_WRITE);
+
+err:
+	b53_srab_release_grant(dev);
+
+	return ret;
+
+}
+
+static int b53_srab_write48(struct b53_device *dev, u8 page, u8 reg,
+				    u64 value)
+{
+	u8 __iomem *regs = dev->priv;
+	int ret = 0;
+
+	ret = b53_srab_request_grant(dev);
+	if (ret)
+		goto err;
+
+	writel((u32)value, regs + B53_SRAB_WD_L);
+	writel((u16)(value >> 32), regs + B53_SRAB_WD_H);
+
+	ret = b53_srab_op(dev, page, reg, B53_SRAB_CMDSTAT_WRITE);
+
+err:
+	b53_srab_release_grant(dev);
+
+	return ret;
+
+}
+
+static int b53_srab_write64(struct b53_device *dev, u8 page, u8 reg,
+			     u64 value)
+{
+	u8 __iomem *regs = dev->priv;
+	int ret = 0;
+
+	ret = b53_srab_request_grant(dev);
+	if (ret)
+		goto err;
+
+	writel((u32)value, regs + B53_SRAB_WD_L);
+	writel((u32)(value >> 32), regs + B53_SRAB_WD_H);
+
+	ret = b53_srab_op(dev, page, reg, B53_SRAB_CMDSTAT_WRITE);
+
+err:
+	b53_srab_release_grant(dev);
+
+	return ret;
+}
+
+static struct b53_io_ops b53_srab_ops = {
+	.read8 = b53_srab_read8,
+	.read16 = b53_srab_read16,
+	.read32 = b53_srab_read32,
+	.read48 = b53_srab_read48,
+	.read64 = b53_srab_read64,
+	.write8 = b53_srab_write8,
+	.write16 = b53_srab_write16,
+	.write32 = b53_srab_write32,
+	.write48 = b53_srab_write48,
+	.write64 = b53_srab_write64,
+};
+
+static int b53_srab_probe(struct platform_device *pdev)
+{
+	struct b53_platform_data *pdata = pdev->dev.platform_data;
+	struct b53_device *dev;
+
+	if (!pdata)
+		return -EINVAL;
+
+	dev = b53_switch_alloc(&pdev->dev, &b53_srab_ops, pdata->regs);
+	if (!dev)
+		return -ENOMEM;
+
+	if (pdata)
+		dev->pdata = pdata;
+
+	pdev->dev.platform_data = dev;
+
+	return b53_switch_register(dev);
+}
+
+static int b53_srab_remove(struct platform_device *pdev)
+{
+	struct b53_device *dev = pdev->dev.platform_data;
+
+	if (dev) {
+		pdev->dev.platform_data = dev->pdata;
+		b53_switch_remove(dev);
+	}
+
+	return 0;
+}
+
+static struct platform_driver b53_srab_driver = {
+	.probe = b53_srab_probe,
+	.remove = b53_srab_remove,
+	.driver = {
+		.name = "b53-srab-switch",
+	},
+};
+
+module_platform_driver(b53_srab_driver);
+MODULE_AUTHOR("Hauke Mehrtens <hauke@hauke-m.de>");
+MODULE_DESCRIPTION("B53 Switch Register Access Bridge Registers (SRAB) access driver");
+MODULE_LICENSE("Dual BSD/GPL");