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-rw-r--r--target/linux/sunxi/patches-3.12/140-add-a31-reset-driver.patch189
1 files changed, 189 insertions, 0 deletions
diff --git a/target/linux/sunxi/patches-3.12/140-add-a31-reset-driver.patch b/target/linux/sunxi/patches-3.12/140-add-a31-reset-driver.patch
new file mode 100644
index 0000000000..3d48a5fa1f
--- /dev/null
+++ b/target/linux/sunxi/patches-3.12/140-add-a31-reset-driver.patch
@@ -0,0 +1,189 @@
+From d8d7a5805579db687fdfdfda4125b43d6a50e616 Mon Sep 17 00:00:00 2001
+From: Maxime Ripard <maxime.ripard@free-electrons.com>
+Date: Tue, 24 Sep 2013 11:07:43 +0300
+Subject: [PATCH] reset: Add Allwinner A31 Reset Controller Driver
+
+The Allwinner A31 has an IP maintaining a few other IPs in the SoC in
+reset by default. Among these IPs are the High Speed Timers, hence why
+we can't use the regular driver construct, and need to call the
+registering function directly during machine initialisation.
+
+Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
+---
+ drivers/reset/Makefile | 1 +
+ drivers/reset/reset-sunxi.c | 156 ++++++++++++++++++++++++++++++++++++++++++++
+ 2 files changed, 157 insertions(+)
+ create mode 100644 drivers/reset/reset-sunxi.c
+
+diff --git a/drivers/reset/Makefile b/drivers/reset/Makefile
+index 1e2d83f..f216b74 100644
+--- a/drivers/reset/Makefile
++++ b/drivers/reset/Makefile
+@@ -1 +1,2 @@
+ obj-$(CONFIG_RESET_CONTROLLER) += core.o
++obj-$(CONFIG_ARCH_SUNXI) += reset-sun6i.o
+diff --git a/drivers/reset/reset-sunxi.c b/drivers/reset/reset-sunxi.c
+new file mode 100644
+index 0000000..5bbd59a
+--- /dev/null
++++ b/drivers/reset/reset-sunxi.c
+@@ -0,0 +1,156 @@
++/*
++ * Allwinner SoCs Reset Controller driver
++ *
++ * Copyright 2013 Maxime Ripard
++ *
++ * Maxime Ripard <maxime.ripard@free-electrons.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.
++ */
++
++#include <linux/err.h>
++#include <linux/io.h>
++#include <linux/module.h>
++#include <linux/of.h>
++#include <linux/of_address.h>
++#include <linux/platform_device.h>
++#include <linux/reset-controller.h>
++#include <linux/slab.h>
++#include <linux/types.h>
++
++struct sunxi_reset_data {
++ void __iomem *membase;
++ struct reset_controller_dev rcdev;
++};
++
++static int sunxi_reset_assert(struct reset_controller_dev *rcdev,
++ unsigned long id)
++{
++ struct sunxi_reset_data *data = container_of(rcdev,
++ struct sunxi_reset_data,
++ rcdev);
++ int bank = id / BITS_PER_LONG;
++ int offset = id % BITS_PER_LONG;
++ u32 reg = readl(data->membase + (bank * 4));
++
++ writel(reg & ~BIT(offset), data->membase + (bank * 4));
++
++ return 0;
++}
++
++static int sunxi_reset_deassert(struct reset_controller_dev *rcdev,
++ unsigned long id)
++{
++ struct sunxi_reset_data *data = container_of(rcdev,
++ struct sunxi_reset_data,
++ rcdev);
++ int bank = id / BITS_PER_LONG;
++ int offset = id % BITS_PER_LONG;
++ u32 reg = readl(data->membase + (bank * 4));
++
++ writel(reg | BIT(offset), data->membase + (bank * 4));
++
++ return 0;
++}
++
++static struct reset_control_ops sunxi_reset_ops = {
++ .assert = sunxi_reset_assert,
++ .deassert = sunxi_reset_deassert,
++};
++
++static int sunxi_reset_init(struct device_node *np)
++{
++ struct sunxi_reset_data *data;
++ struct resource res;
++ resource_size_t size;
++ int ret;
++
++ data = kzalloc(sizeof(*data), GFP_KERNEL);
++ if (!data)
++ return -ENOMEM;
++
++ ret = of_address_to_resource(np, 0, &res);
++ if (ret)
++ goto err_alloc;
++
++ size = resource_size(&res);
++ data->membase = ioremap(res.start, size);
++ if (!data->membase) {
++ ret = -ENOMEM;
++ goto err_alloc;
++ }
++
++ data->rcdev.owner = THIS_MODULE;
++ data->rcdev.nr_resets = size * 32;
++ data->rcdev.ops = &sunxi_reset_ops;
++ data->rcdev.of_node = np;
++ reset_controller_register(&data->rcdev);
++
++ return 0;
++
++err_alloc:
++ kfree(data);
++ return ret;
++};
++
++/*
++ * These are the reset controller we need to initialize early on in
++ * our system, before we can even think of using a regular device
++ * driver for it.
++ */
++static const struct of_device_id sunxi_early_reset_dt_ids[] __initdata = {
++ { .compatible = "allwinner,sun6i-a31-ahb1-reset", },
++ { /* sentinel */ },
++};
++
++void __init sun6i_reset_init(void)
++{
++ struct device_node *np;
++
++ for_each_matching_node(np, sunxi_early_reset_dt_ids)
++ sunxi_reset_init(np);
++}
++
++/*
++ * And these are the controllers we can register through the regular
++ * device model.
++ */
++static const struct of_device_id sunxi_reset_dt_ids[] = {
++ { .compatible = "allwinner,sun4i-clock-reset", },
++ { /* sentinel */ },
++};
++MODULE_DEVICE_TABLE(of, sunxi_reset_dt_ids);
++
++static int sunxi_reset_probe(struct platform_device *pdev)
++{
++ return sunxi_reset_init(pdev->dev.of_node);
++}
++
++static int sunxi_reset_remove(struct platform_device *pdev)
++{
++ struct sunxi_reset_data *data = platform_get_drvdata(pdev);
++
++ reset_controller_unregister(&data->rcdev);
++ iounmap(data->membase);
++ kfree(data);
++
++ return 0;
++}
++
++static struct platform_driver sunxi_reset_driver = {
++ .probe = sunxi_reset_probe,
++ .remove = sunxi_reset_remove,
++ .driver = {
++ .name = "sunxi-reset",
++ .owner = THIS_MODULE,
++ .of_match_table = sunxi_reset_dt_ids,
++ },
++};
++module_platform_driver(sunxi_reset_driver);
++
++MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com");
++MODULE_DESCRIPTION("Allwinner SoCs Reset Controller Driver");
++MODULE_LICENSE("GPL");
+--
+1.8.4
+