Adding upstream version 5.10.209.upstream/5.10.209

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 314 insertions, 0 deletions

diff --git a/drivers/platform/x86/ibm_rtl.c b/drivers/platform/x86/ibm_rtl.c
new file mode 100644
index 000000000..5fc665f7d
--- /dev/null
+++ b/drivers/platform/x86/ibm_rtl.c
@@ -0,0 +1,314 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * IBM Real-Time Linux driver
+ *
+ * Copyright (C) IBM Corporation, 2010
+ *
+ * Author: Keith Mannthey <kmannth@us.ibm.com>
+ *         Vernon Mauery <vernux@us.ibm.com>
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/delay.h>
+#include <linux/module.h>
+#include <linux/io.h>
+#include <linux/dmi.h>
+#include <linux/efi.h>
+#include <linux/mutex.h>
+#include <asm/bios_ebda.h>
+
+#include <linux/io-64-nonatomic-lo-hi.h>
+
+static bool force;
+module_param(force, bool, 0);
+MODULE_PARM_DESC(force, "Force driver load, ignore DMI data");
+
+static bool debug;
+module_param(debug, bool, 0644);
+MODULE_PARM_DESC(debug, "Show debug output");
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Keith Mannthey <kmmanth@us.ibm.com>");
+MODULE_AUTHOR("Vernon Mauery <vernux@us.ibm.com>");
+
+#define RTL_ADDR_TYPE_IO    1
+#define RTL_ADDR_TYPE_MMIO  2
+
+#define RTL_CMD_ENTER_PRTM  1
+#define RTL_CMD_EXIT_PRTM   2
+
+/* The RTL table as presented by the EBDA: */
+struct ibm_rtl_table {
+	char signature[5]; /* signature should be "_RTL_" */
+	u8 version;
+	u8 rt_status;
+	u8 command;
+	u8 command_status;
+	u8 cmd_address_type;
+	u8 cmd_granularity;
+	u8 cmd_offset;
+	u16 reserve1;
+	u32 cmd_port_address; /* platform dependent address */
+	u32 cmd_port_value;   /* platform dependent value */
+} __attribute__((packed));
+
+/* to locate "_RTL_" signature do a masked 5-byte integer compare */
+#define RTL_SIGNATURE 0x0000005f4c54525fULL
+#define RTL_MASK      0x000000ffffffffffULL
+
+#define RTL_DEBUG(fmt, ...)				\
+do {							\
+	if (debug)					\
+		pr_info(fmt, ##__VA_ARGS__);		\
+} while (0)
+
+static DEFINE_MUTEX(rtl_lock);
+static struct ibm_rtl_table __iomem *rtl_table;
+static void __iomem *ebda_map;
+static void __iomem *rtl_cmd_addr;
+static u8 rtl_cmd_type;
+static u8 rtl_cmd_width;
+
+static void __iomem *rtl_port_map(phys_addr_t addr, unsigned long len)
+{
+	if (rtl_cmd_type == RTL_ADDR_TYPE_MMIO)
+		return ioremap(addr, len);
+	return ioport_map(addr, len);
+}
+
+static void rtl_port_unmap(void __iomem *addr)
+{
+	if (addr && rtl_cmd_type == RTL_ADDR_TYPE_MMIO)
+		iounmap(addr);
+	else
+		ioport_unmap(addr);
+}
+
+static int ibm_rtl_write(u8 value)
+{
+	int ret = 0, count = 0;
+	u32 cmd_port_val;
+
+	RTL_DEBUG("%s(%d)\n", __func__, value);
+
+	value = value == 1 ? RTL_CMD_ENTER_PRTM : RTL_CMD_EXIT_PRTM;
+
+	mutex_lock(&rtl_lock);
+
+	if (ioread8(&rtl_table->rt_status) != value) {
+		iowrite8(value, &rtl_table->command);
+
+		switch (rtl_cmd_width) {
+		case 8:
+			cmd_port_val = ioread8(&rtl_table->cmd_port_value);
+			RTL_DEBUG("cmd_port_val = %u\n", cmd_port_val);
+			iowrite8((u8)cmd_port_val, rtl_cmd_addr);
+			break;
+		case 16:
+			cmd_port_val = ioread16(&rtl_table->cmd_port_value);
+			RTL_DEBUG("cmd_port_val = %u\n", cmd_port_val);
+			iowrite16((u16)cmd_port_val, rtl_cmd_addr);
+			break;
+		case 32:
+			cmd_port_val = ioread32(&rtl_table->cmd_port_value);
+			RTL_DEBUG("cmd_port_val = %u\n", cmd_port_val);
+			iowrite32(cmd_port_val, rtl_cmd_addr);
+			break;
+		}
+
+		while (ioread8(&rtl_table->command)) {
+			msleep(10);
+			if (count++ > 500) {
+				pr_err("Hardware not responding to "
+				       "mode switch request\n");
+				ret = -EIO;
+				break;
+			}
+
+		}
+
+		if (ioread8(&rtl_table->command_status)) {
+			RTL_DEBUG("command_status reports failed command\n");
+			ret = -EIO;
+		}
+	}
+
+	mutex_unlock(&rtl_lock);
+	return ret;
+}
+
+static ssize_t rtl_show_version(struct device *dev,
+                                struct device_attribute *attr,
+                                char *buf)
+{
+	return sprintf(buf, "%d\n", (int)ioread8(&rtl_table->version));
+}
+
+static ssize_t rtl_show_state(struct device *dev,
+                              struct device_attribute *attr,
+                              char *buf)
+{
+	return sprintf(buf, "%d\n", ioread8(&rtl_table->rt_status));
+}
+
+static ssize_t rtl_set_state(struct device *dev,
+                             struct device_attribute *attr,
+                             const char *buf,
+                             size_t count)
+{
+	ssize_t ret;
+
+	if (count < 1 || count > 2)
+		return -EINVAL;
+
+	switch (buf[0]) {
+	case '0':
+		ret = ibm_rtl_write(0);
+		break;
+	case '1':
+		ret = ibm_rtl_write(1);
+		break;
+	default:
+		ret = -EINVAL;
+	}
+	if (ret >= 0)
+		ret = count;
+
+	return ret;
+}
+
+static struct bus_type rtl_subsys = {
+	.name = "ibm_rtl",
+	.dev_name = "ibm_rtl",
+};
+
+static DEVICE_ATTR(version, S_IRUGO, rtl_show_version, NULL);
+static DEVICE_ATTR(state, 0600, rtl_show_state, rtl_set_state);
+
+static struct device_attribute *rtl_attributes[] = {
+	&dev_attr_version,
+	&dev_attr_state,
+	NULL
+};
+
+
+static int rtl_setup_sysfs(void) {
+	int ret, i;
+
+	ret = subsys_system_register(&rtl_subsys, NULL);
+	if (!ret) {
+		for (i = 0; rtl_attributes[i]; i ++)
+			device_create_file(rtl_subsys.dev_root, rtl_attributes[i]);
+	}
+	return ret;
+}
+
+static void rtl_teardown_sysfs(void) {
+	int i;
+	for (i = 0; rtl_attributes[i]; i ++)
+		device_remove_file(rtl_subsys.dev_root, rtl_attributes[i]);
+	bus_unregister(&rtl_subsys);
+}
+
+
+static const struct dmi_system_id ibm_rtl_dmi_table[] __initconst = {
+	{                                                  \
+		.matches = {                               \
+			DMI_MATCH(DMI_SYS_VENDOR, "IBM"),  \
+		},                                         \
+	},
+	{ }
+};
+
+static int __init ibm_rtl_init(void) {
+	unsigned long ebda_addr, ebda_size;
+	unsigned int ebda_kb;
+	int ret = -ENODEV, i;
+
+	if (force)
+		pr_warn("module loaded by force\n");
+	/* first ensure that we are running on IBM HW */
+	else if (efi_enabled(EFI_BOOT) || !dmi_check_system(ibm_rtl_dmi_table))
+		return -ENODEV;
+
+	/* Get the address for the Extended BIOS Data Area */
+	ebda_addr = get_bios_ebda();
+	if (!ebda_addr) {
+		RTL_DEBUG("no BIOS EBDA found\n");
+		return -ENODEV;
+	}
+
+	ebda_map = ioremap(ebda_addr, 4);
+	if (!ebda_map)
+		return -ENOMEM;
+
+	/* First word in the EDBA is the Size in KB */
+	ebda_kb = ioread16(ebda_map);
+	RTL_DEBUG("EBDA is %d kB\n", ebda_kb);
+
+	if (ebda_kb == 0)
+		goto out;
+
+	iounmap(ebda_map);
+	ebda_size = ebda_kb*1024;
+
+	/* Remap the whole table */
+	ebda_map = ioremap(ebda_addr, ebda_size);
+	if (!ebda_map)
+		return -ENOMEM;
+
+	/* search for the _RTL_ signature at the start of the table */
+	for (i = 0 ; i < ebda_size/sizeof(unsigned int); i++) {
+		struct ibm_rtl_table __iomem * tmp;
+		tmp = (struct ibm_rtl_table __iomem *) (ebda_map+i);
+		if ((readq(&tmp->signature) & RTL_MASK) == RTL_SIGNATURE) {
+			phys_addr_t addr;
+			unsigned int plen;
+			RTL_DEBUG("found RTL_SIGNATURE at %p\n", tmp);
+			rtl_table = tmp;
+			/* The address, value, width and offset are platform
+			 * dependent and found in the ibm_rtl_table */
+			rtl_cmd_width = ioread8(&rtl_table->cmd_granularity);
+			rtl_cmd_type = ioread8(&rtl_table->cmd_address_type);
+			RTL_DEBUG("rtl_cmd_width = %u, rtl_cmd_type = %u\n",
+				  rtl_cmd_width, rtl_cmd_type);
+			addr = ioread32(&rtl_table->cmd_port_address);
+			RTL_DEBUG("addr = %#llx\n", (unsigned long long)addr);
+			plen = rtl_cmd_width/sizeof(char);
+			rtl_cmd_addr = rtl_port_map(addr, plen);
+			RTL_DEBUG("rtl_cmd_addr = %p\n", rtl_cmd_addr);
+			if (!rtl_cmd_addr) {
+				ret = -ENOMEM;
+				break;
+			}
+			ret = rtl_setup_sysfs();
+			break;
+		}
+	}
+
+out:
+	if (ret) {
+		iounmap(ebda_map);
+		rtl_port_unmap(rtl_cmd_addr);
+	}
+
+	return ret;
+}
+
+static void __exit ibm_rtl_exit(void)
+{
+	if (rtl_table) {
+		RTL_DEBUG("cleaning up");
+		/* do not leave the machine in SMI-free mode */
+		ibm_rtl_write(0);
+		/* unmap, unlink and remove all traces */
+		rtl_teardown_sysfs();
+		iounmap(ebda_map);
+		rtl_port_unmap(rtl_cmd_addr);
+	}
+}
+
+module_init(ibm_rtl_init);
+module_exit(ibm_rtl_exit);