Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
From:   Andrea Greco <andrea.greco.gapmilano@gmail.com>
To:     m.grzeschik@pengutronix.de
Cc:     Andrea Greco <a.greco@4sigma.it>, Rob Herring <robh+dt@kernel.org>,
        Mark Rutland <mark.rutland@arm.com>, netdev@vger.kernel.org,
        devicetree@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [RFC PATCH 1/3] arcnet: com20020: Add memory map of com20020
Date:   Sat,  5 May 2018 23:34:45 +0200
Message-Id: <20180505213448.8180-1-andrea.greco.gapmilano@gmail.com>
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

From: Andrea Greco <a.greco@4sigma.it>

Add support for com20022I/com20020, memory mapped chip version.
Support bus: Intel 80xx and Motorola 68xx.
Bus size: Only 8 bit bus size is supported.
Added related device tree bindings

Signed-off-by: Andrea Greco <a.greco@4sigma.it>
---
 .../devicetree/bindings/net/smsc-com20020.txt      |  23 +++
 drivers/net/arcnet/Kconfig                         |  12 +-
 drivers/net/arcnet/Makefile                        |   1 +
 drivers/net/arcnet/arcdevice.h                     |  27 ++-
 drivers/net/arcnet/com20020-membus.c               | 191 +++++++++++++++++++++
 drivers/net/arcnet/com20020.c                      |   9 +-
 6 files changed, 253 insertions(+), 10 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/net/smsc-com20020.txt
 create mode 100644 drivers/net/arcnet/com20020-membus.c

diff --git a/Documentation/devicetree/bindings/net/smsc-com20020.txt b/Documentation/devicetree/bindings/net/smsc-com20020.txt
new file mode 100644
index 000000000000..39c5b19c55af
--- /dev/null
+++ b/Documentation/devicetree/bindings/net/smsc-com20020.txt
@@ -0,0 +1,23 @@
+SMSC com20020, com20022I
+
+timeout: Arcnet timeout, checkout datashet
+clockp: Clock Prescaler, checkout datashet
+clockm: Clock multiplier, checkout datasheet
+
+phy-reset-gpios: Chip reset ppin
+phy-irq-gpios: Chip irq pin
+
+com20020_A@0 {
+    compatible = "smsc,com20020";
+
+	timeout	= <0x3>;
+	backplane = <0x0>;
+
+	clockp = <0x0>;
+	clockm = <0x3>;
+
+	phy-reset-gpios = <&gpio3 21 GPIO_ACTIVE_LOW>;
+	phy-irq-gpios = <&gpio2 10 GPIO_ACTIVE_LOW>;
+
+	status = "okay";
+};
diff --git a/drivers/net/arcnet/Kconfig b/drivers/net/arcnet/Kconfig
index 39bd16f3f86d..d39faf45be1e 100644
--- a/drivers/net/arcnet/Kconfig
+++ b/drivers/net/arcnet/Kconfig
@@ -3,7 +3,7 @@
 #
 
 menuconfig ARCNET
-	depends on NETDEVICES && (ISA || PCI || PCMCIA)
+	depends on NETDEVICES
 	tristate "ARCnet support"
 	---help---
 	  If you have a network card of this type, say Y and check out the
@@ -129,5 +129,15 @@ config ARCNET_COM20020_CS
 
 	  To compile this driver as a module, choose M here: the module will be
 	  called com20020_cs.  If unsure, say N.
+config ARCNET_COM20020_MEMORY_BUS
+	bool "Support for COM20020 on external memory"
+	depends on ARCNET_COM20020 && !(ARCNET_COM20020_PCI || ARCNET_COM20020_ISA || ARCNET_COM20020_CS)
+	help
+	  Say Y here if on your custom board mount com20020 or friends.
+
+	  Com20022I support arcnet bus 10Mbitps.
+	  This driver support only 8bit, and DMA is not supported is attached on your board at external interface bus.
+	  Supported bus Intel80xx / Motorola 68xx.
+	  This driver not work with other com20020 module: PCI or PCMCIA compiled as [M].
 
 endif # ARCNET
diff --git a/drivers/net/arcnet/Makefile b/drivers/net/arcnet/Makefile
index 53525e8ea130..19425c1e06f4 100644
--- a/drivers/net/arcnet/Makefile
+++ b/drivers/net/arcnet/Makefile
@@ -14,3 +14,4 @@ obj-$(CONFIG_ARCNET_COM20020) += com20020.o
 obj-$(CONFIG_ARCNET_COM20020_ISA) += com20020-isa.o
 obj-$(CONFIG_ARCNET_COM20020_PCI) += com20020-pci.o
 obj-$(CONFIG_ARCNET_COM20020_CS) += com20020_cs.o
+obj-$(CONFIG_ARCNET_COM20020_MEMORY_BUS) += com20020-membus.o
diff --git a/drivers/net/arcnet/arcdevice.h b/drivers/net/arcnet/arcdevice.h
index d09b2b46ab63..16c608269cca 100644
--- a/drivers/net/arcnet/arcdevice.h
+++ b/drivers/net/arcnet/arcdevice.h
@@ -201,7 +201,7 @@ struct ArcProto {
 	void (*rx)(struct net_device *dev, int bufnum,
 		   struct archdr *pkthdr, int length);
 	int (*build_header)(struct sk_buff *skb, struct net_device *dev,
-			    unsigned short ethproto, uint8_t daddr);
+				unsigned short ethproto, uint8_t daddr);
 
 	/* these functions return '1' if the skb can now be freed */
 	int (*prepare_tx)(struct net_device *dev, struct archdr *pkt,
@@ -326,9 +326,9 @@ struct arcnet_local {
 		void (*recontrigger) (struct net_device * dev, int enable);
 
 		void (*copy_to_card)(struct net_device *dev, int bufnum,
-				     int offset, void *buf, int count);
+					 int offset, void *buf, int count);
 		void (*copy_from_card)(struct net_device *dev, int bufnum,
-				       int offset, void *buf, int count);
+					   int offset, void *buf, int count);
 	} hw;
 
 	void __iomem *mem_start;	/* pointer to ioremap'ed MMIO */
@@ -360,7 +360,7 @@ struct net_device *alloc_arcdev(const char *name);
 int arcnet_open(struct net_device *dev);
 int arcnet_close(struct net_device *dev);
 netdev_tx_t arcnet_send_packet(struct sk_buff *skb,
-			       struct net_device *dev);
+				   struct net_device *dev);
 void arcnet_timeout(struct net_device *dev);
 
 /* I/O equivalents */
@@ -371,7 +371,23 @@ void arcnet_timeout(struct net_device *dev);
 #define BUS_ALIGN  1
 #endif
 
-/* addr and offset allow register like names to define the actual IO  address.
+#ifdef CONFIG_ARCNET_COM20020_MEMORY_BUS
+#define arcnet_inb(addr, offset)					\
+	ioread8((void __iomem *)(addr) + BUS_ALIGN * (offset))
+
+#define arcnet_outb(value, addr, offset)				\
+	iowrite8(value, (void __iomem *)(addr) + BUS_ALIGN * (offset))
+
+#define arcnet_insb(addr, offset, buffer, count)			\
+	ioread8_rep((void __iomem *)					\
+	(addr) + BUS_ALIGN * (offset), buffer, count)
+
+#define arcnet_outsb(addr, offset, buffer, count)			\
+	iowrite8_rep((void __iomem *)					\
+	(addr) + BUS_ALIGN * (offset), buffer, count)
+#else
+/**
+ * addr and offset allow register like names to define the actual IO  address.
  * A configuration option multiplies the offset for alignment.
  */
 #define arcnet_inb(addr, offset)					\
@@ -388,6 +404,7 @@ void arcnet_timeout(struct net_device *dev);
 	readb((addr) + (offset))
 #define arcnet_writeb(value, addr, offset)				\
 	writeb(value, (addr) + (offset))
+#endif
 
 #endif				/* __KERNEL__ */
 #endif				/* _LINUX_ARCDEVICE_H */
diff --git a/drivers/net/arcnet/com20020-membus.c b/drivers/net/arcnet/com20020-membus.c
new file mode 100644
index 000000000000..6e4a2f3a84f7
--- /dev/null
+++ b/drivers/net/arcnet/com20020-membus.c
@@ -0,0 +1,191 @@
+// SPDX-License-Identifier: (GPL-2.0 OR MIT)
+/* Linux ARCnet driver for com 20020.
+ *
+ * This datasheet:
+ * http://ww1.microchip.com/downloads/en/DeviceDoc/200223vrevc.pdf
+ * http://ww1.microchip.com/downloads/en/DeviceDoc/20020.pdf
+ *
+ * This driver support:
+ * - com20020,
+ * - com20022
+ * - com20022I-3v3
+ *
+ * This driver support only, 8bit read and write.
+ * DMA is not supported by this driver.
+ */
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/platform_device.h>
+#include <linux/netdevice.h>
+#include <linux/of_address.h>
+#include <linux/of_gpio.h>
+#include <linux/sizes.h>
+#include <linux/interrupt.h>
+#include <linux/ioport.h>
+#include <linux/random.h>
+
+#include <linux/delay.h>
+#include "arcdevice.h"
+#include "com20020.h"
+
+#define VERSION "arcnet: COM20020 MEMORY BUS support loaded.\n"
+
+static int com20020_probe(struct platform_device *pdev)
+{
+	struct device_node *np;
+	struct net_device *dev;
+	struct arcnet_local *lp;
+	struct resource res, *iores;
+	int ret, phy_reset, err;
+	u32 timeout, backplane, clockp, clockm;
+	void __iomem *ioaddr;
+
+	np = pdev->dev.of_node;
+
+	iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+
+	if (of_address_to_resource(np, 0, &res))
+		return -EINVAL;
+
+	ret = of_property_read_u32(np, "timeout", &timeout);
+	if (ret) {
+		dev_err(&pdev->dev, "timeout is required param");
+		return ret;
+	}
+
+	ret = of_property_read_u32(np, "backplane", &backplane);
+	if (ret) {
+		dev_err(&pdev->dev, "backplane is required param");
+		return ret;
+	}
+
+	ret = of_property_read_u32(np, "clockp", &clockp);
+	if (ret) {
+		dev_err(&pdev->dev, "clockp is required param");
+		return ret;
+	}
+
+	ret = of_property_read_u32(np, "clockm", &clockm);
+	if (ret) {
+		dev_err(&pdev->dev, "clockm is required param");
+		return ret;
+	}
+
+	phy_reset = of_get_named_gpio(np, "phy-reset-gpios", 0);
+	if (phy_reset == -EPROBE_DEFER) {
+		return phy_reset;
+	} else if (!gpio_is_valid(phy_reset)) {
+		dev_err(&pdev->dev, "phy-reset-gpios not valid !");
+		return 0;
+	}
+
+	err = devm_gpio_request_one(&pdev->dev, phy_reset, GPIOF_OUT_INIT_LOW,
+				    "arcnet-phy-reset");
+	if (err) {
+		dev_err(&pdev->dev, "failed to get phy-reset-gpios: %d\n", err);
+		return err;
+	}
+
+	dev = alloc_arcdev(NULL);// Let autoassign name arc%d
+	dev->netdev_ops = &com20020_netdev_ops;
+	lp = netdev_priv(dev);
+
+	lp->card_flags = ARC_CAN_10MBIT;/* pretend all of them can 10Mbit */
+
+	// Force address to 0
+	// Will be set by user with `ip set dev arc0 address YOUR_NODE_ID`
+	dev->dev_addr[0] = 0;
+
+	// request to system this memory region
+	if (!devm_request_mem_region(&pdev->dev, res.start, resource_size(&res),
+				     lp->card_name))
+		return -EBUSY;
+
+	ioaddr = devm_ioremap(&pdev->dev, iores->start, resource_size(iores));
+	if (!ioaddr) {
+		dev_err(&pdev->dev, "ioremap fallied\n");
+		return -ENOMEM;
+	}
+
+	// Reset time is 5 * xTalFreq, minimal xtal is 10Mhz
+	// (5 * 1000) / 10Mhz = 500ns
+
+	gpio_set_value_cansleep(phy_reset, 0);
+	ndelay(500);
+	gpio_set_value_cansleep(phy_reset, 1);
+	ndelay(500);
+
+	/* Dummy access after Reset
+	 * ARCNET controller needs
+	 * this access to detect bustype
+	 */
+	arcnet_outb(0x00, ioaddr, COM20020_REG_W_COMMAND);
+	arcnet_inb(ioaddr, COM20020_REG_R_DIAGSTAT);
+
+	dev->base_addr = (unsigned long)ioaddr;
+	get_random_bytes(dev->dev_addr, sizeof(u8));
+
+	dev->irq = of_get_named_gpio(np, "phy-irq-gpios", 0);
+	if (dev->irq == -EPROBE_DEFER) {
+		return dev->irq;
+	} else if (!gpio_is_valid(dev->irq)) {
+		dev_err(&pdev->dev, "phy-irq-gpios not valid !");
+		return 0;
+	}
+	dev->irq = gpio_to_irq(dev->irq);
+
+	lp->backplane = backplane;
+	lp->clockp = clockp & 7;
+	lp->clockm = clockm & 3;
+	lp->timeout = timeout;
+	lp->hw.owner = THIS_MODULE;
+
+	if (arcnet_inb(ioaddr, COM20020_REG_R_STATUS) == 0xFF) {
+		ret = -EIO;
+		goto err_release_mem;
+	}
+
+	if (com20020_check(dev)) {
+		ret = -EIO;
+		goto err_release_mem;
+	}
+
+	ret = com20020_found(dev, IRQF_TRIGGER_FALLING);
+	if (ret)
+		goto err_release_mem;
+
+	dev_dbg(&pdev->dev, "probe Done\n");
+	return 0;
+
+err_release_mem:
+	devm_iounmap(&pdev->dev, (void __iomem *)ioaddr);
+	devm_release_mem_region(&pdev->dev, res.start, resource_size(&res));
+	dev_err(&pdev->dev, "probe failed!\n");
+	return ret;
+}
+
+static const struct of_device_id of_com20020_match[] = {
+	{ .compatible = "smsc,com20020",	},
+	{ },
+};
+
+MODULE_DEVICE_TABLE(of, of_com20020_match);
+
+static struct platform_driver of_com20020_driver = {
+	.driver			= {
+		.name		= "com20020-memory-bus",
+		.of_match_table = of_com20020_match,
+	},
+	.probe			= com20020_probe,
+};
+
+static int com20020_init(void)
+{
+	return platform_driver_register(&of_com20020_driver);
+}
+late_initcall(com20020_init);
+
+MODULE_LICENSE("GPL");
diff --git a/drivers/net/arcnet/com20020.c b/drivers/net/arcnet/com20020.c
index 78043a9c5981..f09ea77dd6a8 100644
--- a/drivers/net/arcnet/com20020.c
+++ b/drivers/net/arcnet/com20020.c
@@ -43,7 +43,7 @@
 #include "com20020.h"
 
 static const char * const clockrates[] = {
-	"XXXXXXX", "XXXXXXXX", "XXXXXX", "2.5 Mb/s",
+	"10 Mb/s", "XXXXXXXX", "XXXXXX", "2.5 Mb/s",
 	"1.25Mb/s", "625 Kb/s", "312.5 Kb/s", "156.25 Kb/s",
 	"Reserved", "Reserved", "Reserved"
 };
@@ -391,9 +391,10 @@ static void com20020_set_mc_list(struct net_device *dev)
 	}
 }
 
-#if defined(CONFIG_ARCNET_COM20020_PCI_MODULE) || \
-    defined(CONFIG_ARCNET_COM20020_ISA_MODULE) || \
-    defined(CONFIG_ARCNET_COM20020_CS_MODULE)
+#if	defined(CONFIG_ARCNET_COM20020_PCI_MODULE) || \
+	defined(CONFIG_ARCNET_COM20020_ISA_MODULE) || \
+	defined(CONFIG_ARCNET_COM20020_CS_MODULE)  || \
+	defined(CONFIG_ARCNET_COM20020_MEMORY_BUS)
 EXPORT_SYMBOL(com20020_check);
 EXPORT_SYMBOL(com20020_found);
 EXPORT_SYMBOL(com20020_netdev_ops);
-- 
2.14.3