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Diffstat (limited to 'arch/x86/include/asm/iosf_mbi.h')
| -rw-r--r-- | arch/x86/include/asm/iosf_mbi.h | 253 |
1 files changed, 253 insertions, 0 deletions
diff --git a/arch/x86/include/asm/iosf_mbi.h b/arch/x86/include/asm/iosf_mbi.h new file mode 100644 index 000000000..a1911fea8 --- /dev/null +++ b/arch/x86/include/asm/iosf_mbi.h @@ -0,0 +1,253 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Intel OnChip System Fabric MailBox access support + */ + +#ifndef IOSF_MBI_SYMS_H +#define IOSF_MBI_SYMS_H + +#include <linux/notifier.h> + +#define MBI_MCR_OFFSET 0xD0 +#define MBI_MDR_OFFSET 0xD4 +#define MBI_MCRX_OFFSET 0xD8 + +#define MBI_RD_MASK 0xFEFFFFFF +#define MBI_WR_MASK 0X01000000 + +#define MBI_MASK_HI 0xFFFFFF00 +#define MBI_MASK_LO 0x000000FF +#define MBI_ENABLE 0xF0 + +/* IOSF SB read/write opcodes */ +#define MBI_MMIO_READ 0x00 +#define MBI_MMIO_WRITE 0x01 +#define MBI_CFG_READ 0x04 +#define MBI_CFG_WRITE 0x05 +#define MBI_CR_READ 0x06 +#define MBI_CR_WRITE 0x07 +#define MBI_REG_READ 0x10 +#define MBI_REG_WRITE 0x11 +#define MBI_ESRAM_READ 0x12 +#define MBI_ESRAM_WRITE 0x13 + +/* Baytrail available units */ +#define BT_MBI_UNIT_AUNIT 0x00 +#define BT_MBI_UNIT_SMC 0x01 +#define BT_MBI_UNIT_CPU 0x02 +#define BT_MBI_UNIT_BUNIT 0x03 +#define BT_MBI_UNIT_PMC 0x04 +#define BT_MBI_UNIT_GFX 0x06 +#define BT_MBI_UNIT_SMI 0x0C +#define BT_MBI_UNIT_CCK 0x14 +#define BT_MBI_UNIT_USB 0x43 +#define BT_MBI_UNIT_SATA 0xA3 +#define BT_MBI_UNIT_PCIE 0xA6 + +/* Quark available units */ +#define QRK_MBI_UNIT_HBA 0x00 +#define QRK_MBI_UNIT_HB 0x03 +#define QRK_MBI_UNIT_RMU 0x04 +#define QRK_MBI_UNIT_MM 0x05 +#define QRK_MBI_UNIT_SOC 0x31 + +/* Action values for the pmic_bus_access_notifier functions */ +#define MBI_PMIC_BUS_ACCESS_BEGIN 1 +#define MBI_PMIC_BUS_ACCESS_END 2 + +#if IS_ENABLED(CONFIG_IOSF_MBI) + +bool iosf_mbi_available(void); + +/** + * iosf_mbi_read() - MailBox Interface read command + * @port: port indicating subunit being accessed + * @opcode: port specific read or write opcode + * @offset: register address offset + * @mdr: register data to be read + * + * Locking is handled by spinlock - cannot sleep. + * Return: Nonzero on error + */ +int iosf_mbi_read(u8 port, u8 opcode, u32 offset, u32 *mdr); + +/** + * iosf_mbi_write() - MailBox unmasked write command + * @port: port indicating subunit being accessed + * @opcode: port specific read or write opcode + * @offset: register address offset + * @mdr: register data to be written + * + * Locking is handled by spinlock - cannot sleep. + * Return: Nonzero on error + */ +int iosf_mbi_write(u8 port, u8 opcode, u32 offset, u32 mdr); + +/** + * iosf_mbi_modify() - MailBox masked write command + * @port: port indicating subunit being accessed + * @opcode: port specific read or write opcode + * @offset: register address offset + * @mdr: register data being modified + * @mask: mask indicating bits in mdr to be modified + * + * Locking is handled by spinlock - cannot sleep. + * Return: Nonzero on error + */ +int iosf_mbi_modify(u8 port, u8 opcode, u32 offset, u32 mdr, u32 mask); + +/** + * iosf_mbi_punit_acquire() - Acquire access to the P-Unit + * + * One some systems the P-Unit accesses the PMIC to change various voltages + * through the same bus as other kernel drivers use for e.g. battery monitoring. + * + * If a driver sends requests to the P-Unit which require the P-Unit to access + * the PMIC bus while another driver is also accessing the PMIC bus various bad + * things happen. + * + * Call this function before sending requests to the P-Unit which may make it + * access the PMIC, be it through iosf_mbi* functions or through other means. + * This function will block all kernel access to the PMIC I2C bus, so that the + * P-Unit can safely access the PMIC over the shared I2C bus. + * + * Note on these systems the i2c-bus driver will request a sempahore from the + * P-Unit for exclusive access to the PMIC bus when i2c drivers are accessing + * it, but this does not appear to be sufficient, we still need to avoid making + * certain P-Unit requests during the access window to avoid problems. + * + * This function locks a mutex, as such it may sleep. + */ +void iosf_mbi_punit_acquire(void); + +/** + * iosf_mbi_punit_release() - Release access to the P-Unit + */ +void iosf_mbi_punit_release(void); + +/** + * iosf_mbi_block_punit_i2c_access() - Block P-Unit accesses to the PMIC bus + * + * Call this function to block P-Unit access to the PMIC I2C bus, so that the + * kernel can safely access the PMIC over the shared I2C bus. + * + * This function acquires the P-Unit bus semaphore and notifies + * pmic_bus_access_notifier listeners that they may no longer access the + * P-Unit in a way which may cause it to access the shared I2C bus. + * + * Note this function may be called multiple times and the bus will not + * be released until iosf_mbi_unblock_punit_i2c_access() has been called the + * same amount of times. + * + * Return: Nonzero on error + */ +int iosf_mbi_block_punit_i2c_access(void); + +/* + * iosf_mbi_unblock_punit_i2c_access() - Release PMIC I2C bus block + * + * Release i2c access block gotten through iosf_mbi_block_punit_i2c_access(). + */ +void iosf_mbi_unblock_punit_i2c_access(void); + +/** + * iosf_mbi_register_pmic_bus_access_notifier - Register PMIC bus notifier + * + * This function can be used by drivers which may need to acquire P-Unit + * managed resources from interrupt context, where iosf_mbi_punit_acquire() + * can not be used. + * + * This function allows a driver to register a notifier to get notified (in a + * process context) before other drivers start accessing the PMIC bus. + * + * This allows the driver to acquire any resources, which it may need during + * the window the other driver is accessing the PMIC, before hand. + * + * @nb: notifier_block to register + */ +int iosf_mbi_register_pmic_bus_access_notifier(struct notifier_block *nb); + +/** + * iosf_mbi_register_pmic_bus_access_notifier - Unregister PMIC bus notifier + * + * @nb: notifier_block to unregister + */ +int iosf_mbi_unregister_pmic_bus_access_notifier(struct notifier_block *nb); + +/** + * iosf_mbi_unregister_pmic_bus_access_notifier_unlocked - Unregister PMIC bus + * notifier, unlocked + * + * Like iosf_mbi_unregister_pmic_bus_access_notifier(), but for use when the + * caller has already called iosf_mbi_punit_acquire() itself. + * + * @nb: notifier_block to unregister + */ +int iosf_mbi_unregister_pmic_bus_access_notifier_unlocked( + struct notifier_block *nb); + +/** + * iosf_mbi_assert_punit_acquired - Assert that the P-Unit has been acquired. + */ +void iosf_mbi_assert_punit_acquired(void); + +#else /* CONFIG_IOSF_MBI is not enabled */ +static inline +bool iosf_mbi_available(void) +{ + return false; +} + +static inline +int iosf_mbi_read(u8 port, u8 opcode, u32 offset, u32 *mdr) +{ + WARN(1, "IOSF_MBI driver not available"); + return -EPERM; +} + +static inline +int iosf_mbi_write(u8 port, u8 opcode, u32 offset, u32 mdr) +{ + WARN(1, "IOSF_MBI driver not available"); + return -EPERM; +} + +static inline +int iosf_mbi_modify(u8 port, u8 opcode, u32 offset, u32 mdr, u32 mask) +{ + WARN(1, "IOSF_MBI driver not available"); + return -EPERM; +} + +static inline void iosf_mbi_punit_acquire(void) {} +static inline void iosf_mbi_punit_release(void) {} + +static inline +int iosf_mbi_register_pmic_bus_access_notifier(struct notifier_block *nb) +{ + return 0; +} + +static inline +int iosf_mbi_unregister_pmic_bus_access_notifier(struct notifier_block *nb) +{ + return 0; +} + +static inline int +iosf_mbi_unregister_pmic_bus_access_notifier_unlocked(struct notifier_block *nb) +{ + return 0; +} + +static inline +int iosf_mbi_call_pmic_bus_access_notifier_chain(unsigned long val, void *v) +{ + return 0; +} + +static inline void iosf_mbi_assert_punit_acquired(void) {} + +#endif /* CONFIG_IOSF_MBI */ + +#endif /* IOSF_MBI_SYMS_H */ |