arch/x86/include/asm/iosf_mbi.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  * Intel OnChip System Fabric MailBox access support
   4  */
   5
   6 #ifndef IOSF_MBI_SYMS_H
   7 #define IOSF_MBI_SYMS_H
   8
   9 #include <linux/notifier.h>
  10
  11 #define MBI_MCR_OFFSET          0xD0
  12 #define MBI_MDR_OFFSET          0xD4
  13 #define MBI_MCRX_OFFSET         0xD8
  14
  15 #define MBI_RD_MASK             0xFEFFFFFF
  16 #define MBI_WR_MASK             0X01000000
  17
  18 #define MBI_MASK_HI             0xFFFFFF00
  19 #define MBI_MASK_LO             0x000000FF
  20 #define MBI_ENABLE              0xF0
  21
  22 /* IOSF SB read/write opcodes */
  23 #define MBI_MMIO_READ           0x00
  24 #define MBI_MMIO_WRITE          0x01
  25 #define MBI_CFG_READ            0x04
  26 #define MBI_CFG_WRITE           0x05
  27 #define MBI_CR_READ             0x06
  28 #define MBI_CR_WRITE            0x07
  29 #define MBI_REG_READ            0x10
  30 #define MBI_REG_WRITE           0x11
  31 #define MBI_ESRAM_READ          0x12
  32 #define MBI_ESRAM_WRITE         0x13
  33
  34 /* Baytrail available units */
  35 #define BT_MBI_UNIT_AUNIT       0x00
  36 #define BT_MBI_UNIT_SMC         0x01
  37 #define BT_MBI_UNIT_CPU         0x02
  38 #define BT_MBI_UNIT_BUNIT       0x03
  39 #define BT_MBI_UNIT_PMC         0x04
  40 #define BT_MBI_UNIT_GFX         0x06
  41 #define BT_MBI_UNIT_SMI         0x0C
  42 #define BT_MBI_UNIT_CCK         0x14
  43 #define BT_MBI_UNIT_USB         0x43
  44 #define BT_MBI_UNIT_SATA        0xA3
  45 #define BT_MBI_UNIT_PCIE        0xA6
  46
  47 /* Quark available units */
  48 #define QRK_MBI_UNIT_HBA        0x00
  49 #define QRK_MBI_UNIT_HB         0x03
  50 #define QRK_MBI_UNIT_RMU        0x04
  51 #define QRK_MBI_UNIT_MM         0x05
  52 #define QRK_MBI_UNIT_SOC        0x31
  53
  54 /* Action values for the pmic_bus_access_notifier functions */
  55 #define MBI_PMIC_BUS_ACCESS_BEGIN       1
  56 #define MBI_PMIC_BUS_ACCESS_END         2
  57
  58 #if IS_ENABLED(CONFIG_IOSF_MBI)
  59
  60 bool iosf_mbi_available(void);
  61
  62 /**
  63  * iosf_mbi_read() - MailBox Interface read command
  64  * @port:       port indicating subunit being accessed
  65  * @opcode:     port specific read or write opcode
  66  * @offset:     register address offset
  67  * @mdr:        register data to be read
  68  *
  69  * Locking is handled by spinlock - cannot sleep.
  70  * Return: Nonzero on error
  71  */
  72 int iosf_mbi_read(u8 port, u8 opcode, u32 offset, u32 *mdr);
  73
  74 /**
  75  * iosf_mbi_write() - MailBox unmasked write command
  76  * @port:       port indicating subunit being accessed
  77  * @opcode:     port specific read or write opcode
  78  * @offset:     register address offset
  79  * @mdr:        register data to be written
  80  *
  81  * Locking is handled by spinlock - cannot sleep.
  82  * Return: Nonzero on error
  83  */
  84 int iosf_mbi_write(u8 port, u8 opcode, u32 offset, u32 mdr);
  85
  86 /**
  87  * iosf_mbi_modify() - MailBox masked write command
  88  * @port:       port indicating subunit being accessed
  89  * @opcode:     port specific read or write opcode
  90  * @offset:     register address offset
  91  * @mdr:        register data being modified
  92  * @mask:       mask indicating bits in mdr to be modified
  93  *
  94  * Locking is handled by spinlock - cannot sleep.
  95  * Return: Nonzero on error
  96  */
  97 int iosf_mbi_modify(u8 port, u8 opcode, u32 offset, u32 mdr, u32 mask);
  98
  99 /**
 100  * iosf_mbi_punit_acquire() - Acquire access to the P-Unit
 101  *
 102  * One some systems the P-Unit accesses the PMIC to change various voltages
 103  * through the same bus as other kernel drivers use for e.g. battery monitoring.
 104  *
 105  * If a driver sends requests to the P-Unit which require the P-Unit to access
 106  * the PMIC bus while another driver is also accessing the PMIC bus various bad
 107  * things happen.
 108  *
 109  * Call this function before sending requests to the P-Unit which may make it
 110  * access the PMIC, be it through iosf_mbi* functions or through other means.
 111  * This function will block all kernel access to the PMIC I2C bus, so that the
 112  * P-Unit can safely access the PMIC over the shared I2C bus.
 113  *
 114  * Note on these systems the i2c-bus driver will request a sempahore from the
 115  * P-Unit for exclusive access to the PMIC bus when i2c drivers are accessing
 116  * it, but this does not appear to be sufficient, we still need to avoid making
 117  * certain P-Unit requests during the access window to avoid problems.
 118  *
 119  * This function locks a mutex, as such it may sleep.
 120  */
 121 void iosf_mbi_punit_acquire(void);
 122
 123 /**
 124  * iosf_mbi_punit_release() - Release access to the P-Unit
 125  */
 126 void iosf_mbi_punit_release(void);
 127
 128 /**
 129  * iosf_mbi_block_punit_i2c_access() - Block P-Unit accesses to the PMIC bus
 130  *
 131  * Call this function to block P-Unit access to the PMIC I2C bus, so that the
 132  * kernel can safely access the PMIC over the shared I2C bus.
 133  *
 134  * This function acquires the P-Unit bus semaphore and notifies
 135  * pmic_bus_access_notifier listeners that they may no longer access the
 136  * P-Unit in a way which may cause it to access the shared I2C bus.
 137  *
 138  * Note this function may be called multiple times and the bus will not
 139  * be released until iosf_mbi_unblock_punit_i2c_access() has been called the
 140  * same amount of times.
 141  *
 142  * Return: Nonzero on error
 143  */
 144 int iosf_mbi_block_punit_i2c_access(void);
 145
 146 /*
 147  * iosf_mbi_unblock_punit_i2c_access() - Release PMIC I2C bus block
 148  *
 149  * Release i2c access block gotten through iosf_mbi_block_punit_i2c_access().
 150  */
 151 void iosf_mbi_unblock_punit_i2c_access(void);
 152
 153 /**
 154  * iosf_mbi_register_pmic_bus_access_notifier - Register PMIC bus notifier
 155  *
 156  * This function can be used by drivers which may need to acquire P-Unit
 157  * managed resources from interrupt context, where iosf_mbi_punit_acquire()
 158  * can not be used.
 159  *
 160  * This function allows a driver to register a notifier to get notified (in a
 161  * process context) before other drivers start accessing the PMIC bus.
 162  *
 163  * This allows the driver to acquire any resources, which it may need during
 164  * the window the other driver is accessing the PMIC, before hand.
 165  *
 166  * @nb: notifier_block to register
 167  */
 168 int iosf_mbi_register_pmic_bus_access_notifier(struct notifier_block *nb);
 169
 170 /**
 171  * iosf_mbi_register_pmic_bus_access_notifier - Unregister PMIC bus notifier
 172  *
 173  * @nb: notifier_block to unregister
 174  */
 175 int iosf_mbi_unregister_pmic_bus_access_notifier(struct notifier_block *nb);
 176
 177 /**
 178  * iosf_mbi_unregister_pmic_bus_access_notifier_unlocked - Unregister PMIC bus
 179  *                                                         notifier, unlocked
 180  *
 181  * Like iosf_mbi_unregister_pmic_bus_access_notifier(), but for use when the
 182  * caller has already called iosf_mbi_punit_acquire() itself.
 183  *
 184  * @nb: notifier_block to unregister
 185  */
 186 int iosf_mbi_unregister_pmic_bus_access_notifier_unlocked(
 187         struct notifier_block *nb);
 188
 189 /**
 190  * iosf_mbi_assert_punit_acquired - Assert that the P-Unit has been acquired.
 191  */
 192 void iosf_mbi_assert_punit_acquired(void);
 193
 194 #else /* CONFIG_IOSF_MBI is not enabled */
 195 static inline
 196 bool iosf_mbi_available(void)
 197 {
 198         return false;
 199 }
 200
 201 static inline
 202 int iosf_mbi_read(u8 port, u8 opcode, u32 offset, u32 *mdr)
 203 {
 204         WARN(1, "IOSF_MBI driver not available");
 205         return -EPERM;
 206 }
 207
 208 static inline
 209 int iosf_mbi_write(u8 port, u8 opcode, u32 offset, u32 mdr)
 210 {
 211         WARN(1, "IOSF_MBI driver not available");
 212         return -EPERM;
 213 }
 214
 215 static inline
 216 int iosf_mbi_modify(u8 port, u8 opcode, u32 offset, u32 mdr, u32 mask)
 217 {
 218         WARN(1, "IOSF_MBI driver not available");
 219         return -EPERM;
 220 }
 221
 222 static inline void iosf_mbi_punit_acquire(void) {}
 223 static inline void iosf_mbi_punit_release(void) {}
 224
 225 static inline
 226 int iosf_mbi_register_pmic_bus_access_notifier(struct notifier_block *nb)
 227 {
 228         return 0;
 229 }
 230
 231 static inline
 232 int iosf_mbi_unregister_pmic_bus_access_notifier(struct notifier_block *nb)
 233 {
 234         return 0;
 235 }
 236
 237 static inline int
 238 iosf_mbi_unregister_pmic_bus_access_notifier_unlocked(struct notifier_block *nb)
 239 {
 240         return 0;
 241 }
 242
 243 static inline
 244 int iosf_mbi_call_pmic_bus_access_notifier_chain(unsigned long val, void *v)
 245 {
 246         return 0;
 247 }
 248
 249 static inline void iosf_mbi_assert_punit_acquired(void) {}
 250
 251 #endif /* CONFIG_IOSF_MBI */
 252
 253 #endif /* IOSF_MBI_SYMS_H */