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path: root/drivers/pnp/pnpbios/bioscalls.c
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Diffstat (limited to 'drivers/pnp/pnpbios/bioscalls.c')
-rw-r--r--drivers/pnp/pnpbios/bioscalls.c490
1 files changed, 490 insertions, 0 deletions
diff --git a/drivers/pnp/pnpbios/bioscalls.c b/drivers/pnp/pnpbios/bioscalls.c
new file mode 100644
index 000000000..ddc6f2163
--- /dev/null
+++ b/drivers/pnp/pnpbios/bioscalls.c
@@ -0,0 +1,490 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * bioscalls.c - the lowlevel layer of the PnPBIOS driver
+ */
+
+#include <linux/types.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/linkage.h>
+#include <linux/kernel.h>
+#include <linux/device.h>
+#include <linux/pnp.h>
+#include <linux/mm.h>
+#include <linux/smp.h>
+#include <linux/kmod.h>
+#include <linux/completion.h>
+#include <linux/spinlock.h>
+
+#include <asm/page.h>
+#include <asm/desc.h>
+#include <asm/byteorder.h>
+
+#include "pnpbios.h"
+
+__visible struct {
+ u16 offset;
+ u16 segment;
+} pnp_bios_callpoint;
+
+/*
+ * These are some opcodes for a "static asmlinkage"
+ * As this code is *not* executed inside the linux kernel segment, but in a
+ * alias at offset 0, we need a far return that can not be compiled by
+ * default (please, prove me wrong! this is *really* ugly!)
+ * This is the only way to get the bios to return into the kernel code,
+ * because the bios code runs in 16 bit protected mode and therefore can only
+ * return to the caller if the call is within the first 64kB, and the linux
+ * kernel begins at offset 3GB...
+ */
+
+asmlinkage __visible void pnp_bios_callfunc(void);
+
+__asm__(".text \n"
+ __ALIGN_STR "\n"
+ ".globl pnp_bios_callfunc\n"
+ "pnp_bios_callfunc:\n"
+ " pushl %edx \n"
+ " pushl %ecx \n"
+ " pushl %ebx \n"
+ " pushl %eax \n"
+ " lcallw *pnp_bios_callpoint\n"
+ " addl $16, %esp \n"
+ " lret \n"
+ ".previous \n");
+
+#define Q2_SET_SEL(cpu, selname, address, size) \
+do { \
+ struct desc_struct *gdt = get_cpu_gdt_rw((cpu)); \
+ set_desc_base(&gdt[(selname) >> 3], (u32)(address)); \
+ set_desc_limit(&gdt[(selname) >> 3], (size) - 1); \
+} while(0)
+
+static struct desc_struct bad_bios_desc = GDT_ENTRY_INIT(0x4092,
+ (unsigned long)__va(0x400UL), PAGE_SIZE - 0x400 - 1);
+
+/*
+ * At some point we want to use this stack frame pointer to unwind
+ * after PnP BIOS oopses.
+ */
+
+__visible u32 pnp_bios_fault_esp;
+__visible u32 pnp_bios_fault_eip;
+__visible u32 pnp_bios_is_utter_crap = 0;
+
+static DEFINE_SPINLOCK(pnp_bios_lock);
+
+/*
+ * Support Functions
+ */
+
+static inline u16 call_pnp_bios(u16 func, u16 arg1, u16 arg2, u16 arg3,
+ u16 arg4, u16 arg5, u16 arg6, u16 arg7,
+ void *ts1_base, u32 ts1_size,
+ void *ts2_base, u32 ts2_size)
+{
+ unsigned long flags;
+ u16 status;
+ struct desc_struct save_desc_40;
+ int cpu;
+
+ /*
+ * PnP BIOSes are generally not terribly re-entrant.
+ * Also, don't rely on them to save everything correctly.
+ */
+ if (pnp_bios_is_utter_crap)
+ return PNP_FUNCTION_NOT_SUPPORTED;
+
+ cpu = get_cpu();
+ save_desc_40 = get_cpu_gdt_rw(cpu)[0x40 / 8];
+ get_cpu_gdt_rw(cpu)[0x40 / 8] = bad_bios_desc;
+
+ /* On some boxes IRQ's during PnP BIOS calls are deadly. */
+ spin_lock_irqsave(&pnp_bios_lock, flags);
+
+ /* The lock prevents us bouncing CPU here */
+ if (ts1_size)
+ Q2_SET_SEL(smp_processor_id(), PNP_TS1, ts1_base, ts1_size);
+ if (ts2_size)
+ Q2_SET_SEL(smp_processor_id(), PNP_TS2, ts2_base, ts2_size);
+
+ __asm__ __volatile__("pushl %%ebp\n\t"
+ "pushl %%edi\n\t"
+ "pushl %%esi\n\t"
+ "pushl %%ds\n\t"
+ "pushl %%es\n\t"
+ "pushl %%fs\n\t"
+ "pushl %%gs\n\t"
+ "pushfl\n\t"
+ "movl %%esp, pnp_bios_fault_esp\n\t"
+ "movl $1f, pnp_bios_fault_eip\n\t"
+ "lcall %5,%6\n\t"
+ "1:popfl\n\t"
+ "popl %%gs\n\t"
+ "popl %%fs\n\t"
+ "popl %%es\n\t"
+ "popl %%ds\n\t"
+ "popl %%esi\n\t"
+ "popl %%edi\n\t"
+ "popl %%ebp\n\t":"=a"(status)
+ :"0"((func) | (((u32) arg1) << 16)),
+ "b"((arg2) | (((u32) arg3) << 16)),
+ "c"((arg4) | (((u32) arg5) << 16)),
+ "d"((arg6) | (((u32) arg7) << 16)),
+ "i"(PNP_CS32), "i"(0)
+ :"memory");
+ spin_unlock_irqrestore(&pnp_bios_lock, flags);
+
+ get_cpu_gdt_rw(cpu)[0x40 / 8] = save_desc_40;
+ put_cpu();
+
+ /* If we get here and this is set then the PnP BIOS faulted on us. */
+ if (pnp_bios_is_utter_crap) {
+ printk(KERN_ERR
+ "PnPBIOS: Warning! Your PnP BIOS caused a fatal error. Attempting to continue\n");
+ printk(KERN_ERR
+ "PnPBIOS: You may need to reboot with the \"pnpbios=off\" option to operate stably\n");
+ printk(KERN_ERR
+ "PnPBIOS: Check with your vendor for an updated BIOS\n");
+ }
+
+ return status;
+}
+
+void pnpbios_print_status(const char *module, u16 status)
+{
+ switch (status) {
+ case PNP_SUCCESS:
+ printk(KERN_ERR "PnPBIOS: %s: function successful\n", module);
+ break;
+ case PNP_NOT_SET_STATICALLY:
+ printk(KERN_ERR "PnPBIOS: %s: unable to set static resources\n",
+ module);
+ break;
+ case PNP_UNKNOWN_FUNCTION:
+ printk(KERN_ERR "PnPBIOS: %s: invalid function number passed\n",
+ module);
+ break;
+ case PNP_FUNCTION_NOT_SUPPORTED:
+ printk(KERN_ERR
+ "PnPBIOS: %s: function not supported on this system\n",
+ module);
+ break;
+ case PNP_INVALID_HANDLE:
+ printk(KERN_ERR "PnPBIOS: %s: invalid handle\n", module);
+ break;
+ case PNP_BAD_PARAMETER:
+ printk(KERN_ERR "PnPBIOS: %s: invalid parameters were passed\n",
+ module);
+ break;
+ case PNP_SET_FAILED:
+ printk(KERN_ERR "PnPBIOS: %s: unable to set resources\n",
+ module);
+ break;
+ case PNP_EVENTS_NOT_PENDING:
+ printk(KERN_ERR "PnPBIOS: %s: no events are pending\n", module);
+ break;
+ case PNP_SYSTEM_NOT_DOCKED:
+ printk(KERN_ERR "PnPBIOS: %s: the system is not docked\n",
+ module);
+ break;
+ case PNP_NO_ISA_PNP_CARDS:
+ printk(KERN_ERR
+ "PnPBIOS: %s: no isapnp cards are installed on this system\n",
+ module);
+ break;
+ case PNP_UNABLE_TO_DETERMINE_DOCK_CAPABILITIES:
+ printk(KERN_ERR
+ "PnPBIOS: %s: cannot determine the capabilities of the docking station\n",
+ module);
+ break;
+ case PNP_CONFIG_CHANGE_FAILED_NO_BATTERY:
+ printk(KERN_ERR
+ "PnPBIOS: %s: unable to undock, the system does not have a battery\n",
+ module);
+ break;
+ case PNP_CONFIG_CHANGE_FAILED_RESOURCE_CONFLICT:
+ printk(KERN_ERR
+ "PnPBIOS: %s: could not dock due to resource conflicts\n",
+ module);
+ break;
+ case PNP_BUFFER_TOO_SMALL:
+ printk(KERN_ERR "PnPBIOS: %s: the buffer passed is too small\n",
+ module);
+ break;
+ case PNP_USE_ESCD_SUPPORT:
+ printk(KERN_ERR "PnPBIOS: %s: use ESCD instead\n", module);
+ break;
+ case PNP_MESSAGE_NOT_SUPPORTED:
+ printk(KERN_ERR "PnPBIOS: %s: the message is unsupported\n",
+ module);
+ break;
+ case PNP_HARDWARE_ERROR:
+ printk(KERN_ERR "PnPBIOS: %s: a hardware failure has occurred\n",
+ module);
+ break;
+ default:
+ printk(KERN_ERR "PnPBIOS: %s: unexpected status 0x%x\n", module,
+ status);
+ break;
+ }
+}
+
+/*
+ * PnP BIOS Low Level Calls
+ */
+
+#define PNP_GET_NUM_SYS_DEV_NODES 0x00
+#define PNP_GET_SYS_DEV_NODE 0x01
+#define PNP_SET_SYS_DEV_NODE 0x02
+#define PNP_GET_EVENT 0x03
+#define PNP_SEND_MESSAGE 0x04
+#define PNP_GET_DOCKING_STATION_INFORMATION 0x05
+#define PNP_SET_STATIC_ALLOCED_RES_INFO 0x09
+#define PNP_GET_STATIC_ALLOCED_RES_INFO 0x0a
+#define PNP_GET_APM_ID_TABLE 0x0b
+#define PNP_GET_PNP_ISA_CONFIG_STRUC 0x40
+#define PNP_GET_ESCD_INFO 0x41
+#define PNP_READ_ESCD 0x42
+#define PNP_WRITE_ESCD 0x43
+
+/*
+ * Call PnP BIOS with function 0x00, "get number of system device nodes"
+ */
+static int __pnp_bios_dev_node_info(struct pnp_dev_node_info *data)
+{
+ u16 status;
+
+ if (!pnp_bios_present())
+ return PNP_FUNCTION_NOT_SUPPORTED;
+ status = call_pnp_bios(PNP_GET_NUM_SYS_DEV_NODES, 0, PNP_TS1, 2,
+ PNP_TS1, PNP_DS, 0, 0, data,
+ sizeof(struct pnp_dev_node_info), NULL, 0);
+ data->no_nodes &= 0xff;
+ return status;
+}
+
+int pnp_bios_dev_node_info(struct pnp_dev_node_info *data)
+{
+ int status = __pnp_bios_dev_node_info(data);
+
+ if (status)
+ pnpbios_print_status("dev_node_info", status);
+ return status;
+}
+
+/*
+ * Note that some PnP BIOSes (e.g., on Sony Vaio laptops) die a horrible
+ * death if they are asked to access the "current" configuration.
+ * Therefore, if it's a matter of indifference, it's better to call
+ * get_dev_node() and set_dev_node() with boot=1 rather than with boot=0.
+ */
+
+/*
+ * Call PnP BIOS with function 0x01, "get system device node"
+ * Input: *nodenum = desired node,
+ * boot = whether to get nonvolatile boot (!=0)
+ * or volatile current (0) config
+ * Output: *nodenum=next node or 0xff if no more nodes
+ */
+static int __pnp_bios_get_dev_node(u8 *nodenum, char boot,
+ struct pnp_bios_node *data)
+{
+ u16 status;
+ u16 tmp_nodenum;
+
+ if (!pnp_bios_present())
+ return PNP_FUNCTION_NOT_SUPPORTED;
+ if (!boot && pnpbios_dont_use_current_config)
+ return PNP_FUNCTION_NOT_SUPPORTED;
+ tmp_nodenum = *nodenum;
+ status = call_pnp_bios(PNP_GET_SYS_DEV_NODE, 0, PNP_TS1, 0, PNP_TS2,
+ boot ? 2 : 1, PNP_DS, 0, &tmp_nodenum,
+ sizeof(tmp_nodenum), data, 65536);
+ *nodenum = tmp_nodenum;
+ return status;
+}
+
+int pnp_bios_get_dev_node(u8 *nodenum, char boot, struct pnp_bios_node *data)
+{
+ int status;
+
+ status = __pnp_bios_get_dev_node(nodenum, boot, data);
+ if (status)
+ pnpbios_print_status("get_dev_node", status);
+ return status;
+}
+
+/*
+ * Call PnP BIOS with function 0x02, "set system device node"
+ * Input: *nodenum = desired node,
+ * boot = whether to set nonvolatile boot (!=0)
+ * or volatile current (0) config
+ */
+static int __pnp_bios_set_dev_node(u8 nodenum, char boot,
+ struct pnp_bios_node *data)
+{
+ u16 status;
+
+ if (!pnp_bios_present())
+ return PNP_FUNCTION_NOT_SUPPORTED;
+ if (!boot && pnpbios_dont_use_current_config)
+ return PNP_FUNCTION_NOT_SUPPORTED;
+ status = call_pnp_bios(PNP_SET_SYS_DEV_NODE, nodenum, 0, PNP_TS1,
+ boot ? 2 : 1, PNP_DS, 0, 0, data, 65536, NULL,
+ 0);
+ return status;
+}
+
+int pnp_bios_set_dev_node(u8 nodenum, char boot, struct pnp_bios_node *data)
+{
+ int status;
+
+ status = __pnp_bios_set_dev_node(nodenum, boot, data);
+ if (status) {
+ pnpbios_print_status("set_dev_node", status);
+ return status;
+ }
+ if (!boot) { /* Update devlist */
+ status = pnp_bios_get_dev_node(&nodenum, boot, data);
+ if (status)
+ return status;
+ }
+ return status;
+}
+
+/*
+ * Call PnP BIOS with function 0x05, "get docking station information"
+ */
+int pnp_bios_dock_station_info(struct pnp_docking_station_info *data)
+{
+ u16 status;
+
+ if (!pnp_bios_present())
+ return PNP_FUNCTION_NOT_SUPPORTED;
+ status = call_pnp_bios(PNP_GET_DOCKING_STATION_INFORMATION, 0, PNP_TS1,
+ PNP_DS, 0, 0, 0, 0, data,
+ sizeof(struct pnp_docking_station_info), NULL,
+ 0);
+ return status;
+}
+
+/*
+ * Call PnP BIOS with function 0x0a, "get statically allocated resource
+ * information"
+ */
+static int __pnp_bios_get_stat_res(char *info)
+{
+ u16 status;
+
+ if (!pnp_bios_present())
+ return PNP_FUNCTION_NOT_SUPPORTED;
+ status = call_pnp_bios(PNP_GET_STATIC_ALLOCED_RES_INFO, 0, PNP_TS1,
+ PNP_DS, 0, 0, 0, 0, info, 65536, NULL, 0);
+ return status;
+}
+
+int pnp_bios_get_stat_res(char *info)
+{
+ int status;
+
+ status = __pnp_bios_get_stat_res(info);
+ if (status)
+ pnpbios_print_status("get_stat_res", status);
+ return status;
+}
+
+/*
+ * Call PnP BIOS with function 0x40, "get isa pnp configuration structure"
+ */
+static int __pnp_bios_isapnp_config(struct pnp_isa_config_struc *data)
+{
+ u16 status;
+
+ if (!pnp_bios_present())
+ return PNP_FUNCTION_NOT_SUPPORTED;
+ status = call_pnp_bios(PNP_GET_PNP_ISA_CONFIG_STRUC, 0, PNP_TS1, PNP_DS,
+ 0, 0, 0, 0, data,
+ sizeof(struct pnp_isa_config_struc), NULL, 0);
+ return status;
+}
+
+int pnp_bios_isapnp_config(struct pnp_isa_config_struc *data)
+{
+ int status;
+
+ status = __pnp_bios_isapnp_config(data);
+ if (status)
+ pnpbios_print_status("isapnp_config", status);
+ return status;
+}
+
+/*
+ * Call PnP BIOS with function 0x41, "get ESCD info"
+ */
+static int __pnp_bios_escd_info(struct escd_info_struc *data)
+{
+ u16 status;
+
+ if (!pnp_bios_present())
+ return ESCD_FUNCTION_NOT_SUPPORTED;
+ status = call_pnp_bios(PNP_GET_ESCD_INFO, 0, PNP_TS1, 2, PNP_TS1, 4,
+ PNP_TS1, PNP_DS, data,
+ sizeof(struct escd_info_struc), NULL, 0);
+ return status;
+}
+
+int pnp_bios_escd_info(struct escd_info_struc *data)
+{
+ int status;
+
+ status = __pnp_bios_escd_info(data);
+ if (status)
+ pnpbios_print_status("escd_info", status);
+ return status;
+}
+
+/*
+ * Call PnP BIOS function 0x42, "read ESCD"
+ * nvram_base is determined by calling escd_info
+ */
+static int __pnp_bios_read_escd(char *data, u32 nvram_base)
+{
+ u16 status;
+
+ if (!pnp_bios_present())
+ return ESCD_FUNCTION_NOT_SUPPORTED;
+ status = call_pnp_bios(PNP_READ_ESCD, 0, PNP_TS1, PNP_TS2, PNP_DS, 0, 0,
+ 0, data, 65536, __va(nvram_base), 65536);
+ return status;
+}
+
+int pnp_bios_read_escd(char *data, u32 nvram_base)
+{
+ int status;
+
+ status = __pnp_bios_read_escd(data, nvram_base);
+ if (status)
+ pnpbios_print_status("read_escd", status);
+ return status;
+}
+
+void pnpbios_calls_init(union pnp_bios_install_struct *header)
+{
+ int i;
+
+ pnp_bios_callpoint.offset = header->fields.pm16offset;
+ pnp_bios_callpoint.segment = PNP_CS16;
+
+ for_each_possible_cpu(i) {
+ struct desc_struct *gdt = get_cpu_gdt_rw(i);
+ if (!gdt)
+ continue;
+ set_desc_base(&gdt[GDT_ENTRY_PNPBIOS_CS32],
+ (unsigned long)&pnp_bios_callfunc);
+ set_desc_base(&gdt[GDT_ENTRY_PNPBIOS_CS16],
+ (unsigned long)__va(header->fields.pm16cseg));
+ set_desc_base(&gdt[GDT_ENTRY_PNPBIOS_DS],
+ (unsigned long)__va(header->fields.pm16dseg));
+ }
+}