// SPDX-License-Identifier: GPL-2.0
/*
* A hack to create a platform device from a DMI entry. This will
* allow autoloading of the IPMI drive based on SMBIOS entries.
*/
#include <linux/ipmi.h>
#include <linux/init.h>
#include <linux/dmi.h>
#include <linux/platform_device.h>
#include <linux/property.h>
#include "ipmi_si_sm.h"
#include "ipmi_dmi.h"
#define IPMI_DMI_TYPE_KCS 0x01
#define IPMI_DMI_TYPE_SMIC 0x02
#define IPMI_DMI_TYPE_BT 0x03
#define IPMI_DMI_TYPE_SSIF 0x04
struct ipmi_dmi_info {
enum si_type si_type;
u32 flags;
unsigned long addr;
u8 slave_addr;
struct ipmi_dmi_info *next;
};
static struct ipmi_dmi_info *ipmi_dmi_infos;
static int ipmi_dmi_nr __initdata;
#define set_prop_entry(_p_, _name_, type, val) \
do { \
struct property_entry *_p = &_p_; \
_p->name = _name_; \
_p->length = sizeof(type); \
_p->is_string = false; \
_p->value.type##_data = val; \
} while(0)
static void __init dmi_add_platform_ipmi(unsigned long base_addr,
u32 flags,
u8 slave_addr,
int irq,
int offset,
int type)
{
struct platform_device *pdev;
struct resource r[4];
unsigned int num_r = 1, size;
struct property_entry p[5];
unsigned int pidx = 0;
char *name, *override;
int rv;
enum si_type si_type;
struct ipmi_dmi_info *info;
memset(p, 0, sizeof(p));
name = "dmi-ipmi-si";
override = "ipmi_si";
switch (type) {
case IPMI_DMI_TYPE_SSIF:
name = "dmi-ipmi-ssif";
override = "ipmi_ssif";
offset = 1;
size = 1;
si_type = SI_TYPE_INVALID;
break;
case IPMI_DMI_TYPE_BT:
size = 3;
si_type = SI_BT;
break;
case IPMI_DMI_TYPE_KCS:
size = 2;
si_type = SI_KCS;
break;
case IPMI_DMI_TYPE_SMIC:
size = 2;
si_type = SI_SMIC;
break;
default:
pr_err("ipmi:dmi: Invalid IPMI type: %d\n", type);
return;
}
if (si_type != SI_TYPE_INVALID)
set_prop_entry(p[pidx++], "ipmi-type", u8, si_type);
set_prop_entry(p[pidx++], "slave-addr", u8, slave_addr);
set_prop_entry(p[pidx++], "addr-source", u8, SI_SMBIOS);
info = kmalloc(sizeof(*info), GFP_KERNEL);
if (!info) {
pr_warn("ipmi:dmi: Could not allocate dmi info\n");
} else {
info->si_type = si_type;
info->flags = flags;
info->addr = base_addr;
info->slave_addr = slave_addr;
info->next = ipmi_dmi_infos;
ipmi_dmi_infos = info;
}
pdev = platform_device_alloc(name, ipmi_dmi_nr);
if (!pdev) {
pr_err("ipmi:dmi: Error allocation IPMI platform device\n");
return;
}
pdev->driver_override = kasprintf(GFP_KERNEL, "%s",
override);
if (!pdev->driver_override)
goto err;
if (type == IPMI_DMI_TYPE_SSIF) {
set_prop_entry(p[pidx++], "i2c-addr", u16, base_addr);
goto add_properties;
}
memset(r, 0, sizeof(r));
r[0].start = base_addr;
r[0].end = r[0].start + offset - 1;
r[0].name = "IPMI Address 1";
r[0].flags = flags;
if (size > 1) {
r[1].start = r[0].start + offset;
r[1].end = r[1].start + offset - 1;
r[1].name = "IPMI Address 2";
r[1].flags = flags;
num_r++;
}
if (size > 2) {
r[2].start = r[1].start + offset;
r[2].end = r[2].start + offset - 1;
r[2].name = "IPMI Address 3";
r[2].flags = flags;
num_r++;
}
if (irq) {
r[num_r].start = irq;
r[num_r].end = irq;
r[num_r].name = "IPMI IRQ";
r[num_r].flags = IORESOURCE_IRQ;
num_r++;
}
rv = platform_device_add_resources(pdev, r, num_r);
if (rv) {
dev_err(&pdev->dev,
"ipmi:dmi: Unable to add resources: %d\n", rv);
goto err;
}
add_properties:
rv = platform_device_add_properties(pdev, p);
if (rv) {
dev_err(&pdev->dev,
"ipmi:dmi: Unable to add properties: %d\n", rv);
goto err;
}
rv = platform_device_add(pdev);
if (rv) {
dev_err(&pdev->dev, "ipmi:dmi: Unable to add device: %d\n", rv);
goto err;
}
ipmi_dmi_nr++;
return;
err:
platform_device_put(pdev);
}
/*
* Look up the slave address for a given interface. This is here
* because ACPI doesn't have a slave address while SMBIOS does, but we
* prefer using ACPI so the ACPI code can use the IPMI namespace.
* This function allows an ACPI-specified IPMI device to look up the
* slave address from the DMI table.
*/
int ipmi_dmi_get_slave_addr(enum si_type si_type, u32 flags,
unsigned long base_addr)
{
struct ipmi_dmi_info *info = ipmi_dmi_infos;
while (info) {
if (info->si_type == si_type &&
info->flags == flags &&
info->addr == base_addr)
return info->slave_addr;
info = info->next;
}
return 0;
}
EXPORT_SYMBOL(ipmi_dmi_get_slave_addr);
#define DMI_IPMI_MIN_LENGTH 0x10
#define DMI_IPMI_VER2_LENGTH 0x12
#define DMI_IPMI_TYPE 4
#define DMI_IPMI_SLAVEADDR 6
#define DMI_IPMI_ADDR 8
#define DMI_IPMI_ACCESS 0x10
#define DMI_IPMI_IRQ 0x11
#define DMI_IPMI_IO_MASK 0xfffe
static void __init dmi_decode_ipmi(const struct dmi_header *dm)
{
const u8 *data = (const u8 *) dm;
u32 flags = IORESOURCE_IO;
unsigned long base_addr;
u8 len = dm->length;
u8 slave_addr;
int irq = 0, offset;
int type;
if (len < DMI_IPMI_MIN_LENGTH)
return;
type = data[DMI_IPMI_TYPE];
slave_addr = data[DMI_IPMI_SLAVEADDR];
memcpy(&base_addr, data + DMI_IPMI_ADDR, sizeof(unsigned long));
if (len >= DMI_IPMI_VER2_LENGTH) {
if (type == IPMI_DMI_TYPE_SSIF) {
offset = 0;
flags = 0;
base_addr = data[DMI_IPMI_ADDR] >> 1;
if (base_addr == 0) {
/*
* Some broken systems put the I2C address in
* the slave address field. We try to
* accommodate them here.
*/
base_addr = data[DMI_IPMI_SLAVEADDR] >> 1;
slave_addr = 0;
}
} else {
if (base_addr & 1) {
/* I/O */
base_addr &= DMI_IPMI_IO_MASK;
} else {
/* Memory */
flags = IORESOURCE_MEM;
}
/*
* If bit 4 of byte 0x10 is set, then the lsb
* for the address is odd.
*/
base_addr |= (data[DMI_IPMI_ACCESS] >> 4) & 1;
irq = data[DMI_IPMI_IRQ];
/*
* The top two bits of byte 0x10 hold the
* register spacing.
*/
switch ((data[DMI_IPMI_ACCESS] >> 6) & 3) {
case 0: /* Byte boundaries */
offset = 1;
break;
case 1: /* 32-bit boundaries */
offset = 4;
break;
case 2: /* 16-byte boundaries */
offset = 16;
break;
default:
pr_err("ipmi:dmi: Invalid offset: 0\n");
return;
}
}
} else {
/* Old DMI spec. */
/*
* Note that technically, the lower bit of the base
* address should be 1 if the address is I/O and 0 if
* the address is in memory. So many systems get that
* wrong (and all that I have seen are I/O) so we just
* ignore that bit and assume I/O. Systems that use
* memory should use the newer spec, anyway.
*/
base_addr = base_addr & DMI_IPMI_IO_MASK;
offset = 1;
}
dmi_add_platform_ipmi(base_addr, flags, slave_addr, irq,
offset, type);
}
static int __init scan_for_dmi_ipmi(void)
{
const struct dmi_device *dev = NULL;
while ((dev = dmi_find_device(DMI_DEV_TYPE_IPMI, NULL, dev)))
dmi_decode_ipmi((const struct dmi_header *) dev->device_data);
return 0;
}
subsys_initcall(scan_for_dmi_ipmi);
