[PATCH 2/3] soc: amazon: al-pos: Introduce Amazon's Annapurna Labs POS driver

From: Talel Shenhar
Date: Mon Sep 09 2019 - 05:14:12 EST

The Amazon's Annapurna Labs SoCs includes Point Of Serialization error
logging unit that reports an error in case write error (e.g. attempt to
write to a read only register).
This patch introduces the support for this unit.

Signed-off-by: Talel Shenhar <talel@xxxxxxxxxx>
---
MAINTAINERS | 6 +++
drivers/soc/Kconfig | 1 +
drivers/soc/Makefile | 1 +
drivers/soc/amazon/Kconfig | 5 ++
drivers/soc/amazon/Makefile | 1 +
drivers/soc/amazon/al_pos.c | 129 ++++++++++++++++++++++++++++++++++++++++++++
6 files changed, 143 insertions(+)
create mode 100644 drivers/soc/amazon/Kconfig
create mode 100644 drivers/soc/amazon/Makefile
create mode 100644 drivers/soc/amazon/al_pos.c

diff --git a/MAINTAINERS b/MAINTAINERS
index e7a47b5..627af40 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -751,6 +751,12 @@ F: drivers/tty/serial/altera_jtaguart.c
F: include/linux/altera_uart.h
F: include/linux/altera_jtaguart.h

+AMAZON ANNAPURNA LABS POS
+M: Talel Shenhar <talel@xxxxxxxxxx>
+S: Maintained
+F: Documentation/devicetree/bindings/soc/amazon/amazon,al-pos.txt
+F: drivers/soc/amazon/al_pos.c
+
AMAZON ANNAPURNA LABS THERMAL MMIO DRIVER
M: Talel Shenhar <talel@xxxxxxxxxx>
S: Maintained
diff --git a/drivers/soc/Kconfig b/drivers/soc/Kconfig
index 833e04a..913a6b1 100644
--- a/drivers/soc/Kconfig
+++ b/drivers/soc/Kconfig
@@ -2,6 +2,7 @@
menu "SOC (System On Chip) specific Drivers"

source "drivers/soc/actions/Kconfig"
+source "drivers/soc/amazon/Kconfig"
source "drivers/soc/amlogic/Kconfig"
source "drivers/soc/aspeed/Kconfig"
source "drivers/soc/atmel/Kconfig"
diff --git a/drivers/soc/Makefile b/drivers/soc/Makefile
index 2ec3550..c1c5c64 100644
--- a/drivers/soc/Makefile
+++ b/drivers/soc/Makefile
@@ -6,6 +6,7 @@
obj-$(CONFIG_ARCH_ACTIONS) += actions/
obj-$(CONFIG_SOC_ASPEED) += aspeed/
obj-$(CONFIG_ARCH_AT91) += atmel/
+obj-y += amazon/
obj-y += bcm/
obj-$(CONFIG_ARCH_DOVE) += dove/
obj-$(CONFIG_MACH_DOVE) += dove/
diff --git a/drivers/soc/amazon/Kconfig b/drivers/soc/amazon/Kconfig
new file mode 100644
index 00000000..fdd4cdd
--- /dev/null
+++ b/drivers/soc/amazon/Kconfig
@@ -0,0 +1,5 @@
+config AL_POS
+ bool "Amazon's Annapurna Labs POS driver"
+ depends on ARCH_ALPINE || COMPILE_TEST
+ help
+ Include support for the SoC POS error capability.
diff --git a/drivers/soc/amazon/Makefile b/drivers/soc/amazon/Makefile
new file mode 100644
index 00000000..a31441a
--- /dev/null
+++ b/drivers/soc/amazon/Makefile
@@ -0,0 +1 @@
+obj-$(CONFIG_AL_POS) += al_pos.o
diff --git a/drivers/soc/amazon/al_pos.c b/drivers/soc/amazon/al_pos.c
new file mode 100644
index 00000000..6d0bdff
--- /dev/null
+++ b/drivers/soc/amazon/al_pos.c
@@ -0,0 +1,129 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ */
+#include <linux/bitfield.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/of_platform.h>
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Talel Shenhar");
+MODULE_DESCRIPTION("Amazon's Annapurna Labs POS driver");
+
+/* Registers Offset */
+#define AL_POS_ERROR_LOG_1 0x0
+#define AL_POS_ERROR_LOG_0 0x4
+
+/* Registers Fields */
+#define AL_POS_ERROR_LOG_1_VALID GENMASK(31, 31)
+#define AL_POS_ERROR_LOG_1_BRESP GENMASK(18, 17)
+#define AL_POS_ERROR_LOG_1_REQUEST_ID GENMASK(16, 8)
+#define AL_POS_ERROR_LOG_1_ADDR_HIGH GENMASK(7, 0)
+
+#define AL_POS_ERROR_LOG_0_ADDR_LOW GENMASK(31, 0)
+
+static int al_pos_panic;
+module_param(al_pos_panic, int, 0);
+MODULE_PARM_DESC(al_pos_panic, "Defines if POS error is causing panic()");
+
+struct al_pos {
+ struct platform_device *pdev;
+ void __iomem *mmio_base;
+ int irq;
+};
+
+static irqreturn_t al_pos_irq_handler(int irq, void *info)
+{
+ struct platform_device *pdev = info;
+ struct al_pos *pos = platform_get_drvdata(pdev);
+ u32 log1;
+ u32 log0;
+ u64 addr;
+ u16 request_id;
+ u8 bresp;
+
+ log1 = readl_relaxed(pos->mmio_base + AL_POS_ERROR_LOG_1);
+ if (!FIELD_GET(AL_POS_ERROR_LOG_1_VALID, log1))
+ return IRQ_NONE;
+
+ log0 = readl_relaxed(pos->mmio_base + AL_POS_ERROR_LOG_0);
+ writel_relaxed(0, pos->mmio_base + AL_POS_ERROR_LOG_1);
+
+ addr = FIELD_GET(AL_POS_ERROR_LOG_0_ADDR_LOW, log0);
+ addr |= (FIELD_GET(AL_POS_ERROR_LOG_1_ADDR_HIGH, log1) << 32);
+ request_id = FIELD_GET(AL_POS_ERROR_LOG_1_REQUEST_ID, log1);
+ bresp = FIELD_GET(AL_POS_ERROR_LOG_1_BRESP, log1);
+
+ dev_err(&pdev->dev, "addr=0x%llx request_id=0x%x bresp=0x%x\n",
+ addr, request_id, bresp);
+
+ if (al_pos_panic)
+ panic("POS");
+
+ return IRQ_HANDLED;
+}
+
+static int al_pos_probe(struct platform_device *pdev)
+{
+ struct al_pos *pos;
+ struct resource *resource;
+ int ret;
+
+ pos = devm_kzalloc(&pdev->dev, sizeof(*pos), GFP_KERNEL);
+ if (!pos)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, pos);
+ pos->pdev = pdev;
+
+ resource = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ pos->mmio_base = devm_ioremap_resource(&pdev->dev, resource);
+ if (IS_ERR(pos->mmio_base)) {
+ dev_err(&pdev->dev, "failed to ioremap memory (%ld)\n",
+ PTR_ERR(pos->mmio_base));
+ return PTR_ERR(pos->mmio_base);
+ }
+
+ pos->irq = irq_of_parse_and_map(pdev->dev.of_node, 0);
+ if (pos->irq <= 0) {
+ dev_err(&pdev->dev, "fail to parse and map irq\n");
+ return -EINVAL;
+ }
+
+ ret = devm_request_irq(&pdev->dev,
+ pos->irq,
+ al_pos_irq_handler,
+ 0,
+ pdev->name,
+ pdev);
+ if (ret != 0) {
+ dev_err(&pdev->dev,
+ "failed to register to irq %d (%d)\n",
+ pos->irq, ret);
+ return ret;
+ }
+
+ dev_info(&pdev->dev, "successfully loaded\n");
+
+ return 0;
+}
+
+static const struct of_device_id al_pos_of_match[] = {
+ { .compatible = "amazon,al-pos", },
+ {},
+};
+
+MODULE_DEVICE_TABLE(of, al_pos_of_match);
+
+static struct platform_driver al_pos_driver = {
+ .probe = al_pos_probe,
+ .driver = {
+ .name = "al-pos",
+ .of_match_table = al_pos_of_match,
+ },
+};
+
+module_platform_driver(al_pos_driver);
--
2.7.4