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