pci_save_config_regs(9f)

1pci_save_config_regs(9F) Kernel Functions for Drivers pci_save_config_regs(9F)
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NAME

6       pci_save_config_regs,  pci_restore_config_regs  -  save and restore the
7       PCI configuration registers
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SYNOPSIS

10       #include <sys/ddi.h>
11       #include <sys/sunddi.h>
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15       int pci_save_config_regs(dev_info_t *dip);
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18       int pci_restore_config_regs(dev_info_t *dip);
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INTERFACE LEVEL

22       Solaris DDI-specific (Solaris DDI).
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ARGUMENTS

25       dip    Pointer to the device's dev_info structure.
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DESCRIPTION

29       pci_save_config_regs() saves the  current  configuration  registers  on
30       persistent system memory. pci_restore_config_regs() restores configura‐
31       tion registers previously saved by pci_save_config_regs().
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34       pci_save_config_regs() should be called by the driver's  power()  entry
35       point  before  powering  a  device  off  (to  PCI  state D3). Likewise,
36       pci_restore_config_regs() should be called after powering a  device  on
37       (from PCI state D3), but before accessing the device. See power(9E).
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RETURN VALUES

40       pci_save_config_regs() and pci_restore_config_regs() return:
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42       DDI_SUCCESS    Operation completed successfully.
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45       DDI_FAILURE    Operation failed to complete successfully.
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CONTEXT

49       Both these functions can be called from user or kernel context.
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EXAMPLES

52       Example 1 Invoking the save and restore functions
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54         static int
55         xx_power(dev_info_t *dip, int component, int level) {
56            struct xx *xx;
57            int rval = DDI_SUCCESS;
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59            xx = ddi_get_soft_state(xx_softstate, ddi_get_instance(dip));
60            if (xx == NULL) {
61                return (DDI_FAILURE);
62            }
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64            mutex_enter(&xx−>x_mutex);
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66            switch (level) {
67            case PM_LEVEL_D0:
68                XX_POWER_ON(xx);
69                if (pci_restore_config_regs(dip) == DDI_FAILURE) {
70                    /*
71                     * appropriate error path handling here
72                     */
73                    ...
74                    rval = DDI_FAILURE;
75                    }
76                break;
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78            case PM_LEVEL_D3:
79                if (pci_save_config_regs(dip) == DDI_FAILURE) {
80                     /*
81                      * appropriate error path handling here
82                      */
83                     ...
84                     rval = DDI_FAILURE;
85                     }
86                 else {
87                     XX_POWER_OFF(xx);
88                 }
89                 break;
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91             default:
92                   rval = DDI_FAILURE;
93                   break;
94             }
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96             mutex_exit(&xx−>x_mutex);
97             return (rval);
98         }
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ATTRIBUTES

102       See attributes(5) for descriptions of the following attributes:
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107       ┌─────────────────────────────┬─────────────────────────────┐
108       │      ATTRIBUTE TYPE         │      ATTRIBUTE VALUE        │
109       ├─────────────────────────────┼─────────────────────────────┤
110       │Interface Stability          │Committed                    │
111       └─────────────────────────────┴─────────────────────────────┘
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