diff options
| -rw-r--r-- | drivers/fsi/fsi-core.c | 121 |
1 files changed, 114 insertions, 7 deletions
diff --git a/drivers/fsi/fsi-core.c b/drivers/fsi/fsi-core.c index db54561161ac..c9ff8d3b3f03 100644 --- a/drivers/fsi/fsi-core.c +++ b/drivers/fsi/fsi-core.c @@ -46,7 +46,9 @@ static const int engine_page_size = 0x400; /* * FSI slave engine control register offsets */ -#define FSI_SMODE 0x0 /* R/W: Mode register */ +#define FSI_SMODE 0x0 /* R/W: Mode register */ +#define FSI_SISC 0x8 /* R/W: Interrupt condition */ +#define FSI_SSTAT 0x14 /* R : Slave status */ /* * SMODE fields @@ -77,10 +79,14 @@ struct fsi_slave { #define to_fsi_master(d) container_of(d, struct fsi_master, dev) #define to_fsi_slave(d) container_of(d, struct fsi_slave, dev) +static const int slave_retries = 2; +static int discard_errors; + static int fsi_master_read(struct fsi_master *master, int link, uint8_t slave_id, uint32_t addr, void *val, size_t size); static int fsi_master_write(struct fsi_master *master, int link, uint8_t slave_id, uint32_t addr, const void *val, size_t size); +static int fsi_master_break(struct fsi_master *master, int link); /* * fsi_device_read() / fsi_device_write() / fsi_device_peek() @@ -173,18 +179,107 @@ static int fsi_slave_calc_addr(struct fsi_slave *slave, uint32_t *addrp, return 0; } +int fsi_slave_report_and_clear_errors(struct fsi_slave *slave) +{ + struct fsi_master *master = slave->master; + uint32_t irq, stat; + int rc, link; + uint8_t id; + + link = slave->link; + id = slave->id; + + rc = fsi_master_read(master, link, id, FSI_SLAVE_BASE + FSI_SISC, + &irq, sizeof(irq)); + if (rc) + return rc; + + rc = fsi_master_read(master, link, id, FSI_SLAVE_BASE + FSI_SSTAT, + &stat, sizeof(stat)); + if (rc) + return rc; + + dev_info(&slave->dev, "status: 0x%08x, sisc: 0x%08x\n", + be32_to_cpu(stat), be32_to_cpu(irq)); + + /* clear interrupts */ + return fsi_master_write(master, link, id, FSI_SLAVE_BASE + FSI_SISC, + &irq, sizeof(irq)); +} + +static int fsi_slave_set_smode(struct fsi_master *master, int link, int id); + +int fsi_slave_handle_error(struct fsi_slave *slave, bool write, uint32_t addr, + size_t size) +{ + struct fsi_master *master = slave->master; + int rc, link; + uint32_t reg; + uint8_t id; + + if (discard_errors) + return -1; + + link = slave->link; + id = slave->id; + + dev_dbg(&slave->dev, "handling error on %s to 0x%08x[%zd]", + write ? "write" : "read", addr, size); + + /* try a simple clear of error conditions, which may fail if we've lost + * communication with the slave + */ + rc = fsi_slave_report_and_clear_errors(slave); + if (!rc) + return 0; + + /* send a TERM and retry */ + if (master->term) { + rc = master->term(master, link, id); + if (!rc) { + rc = fsi_master_read(master, link, id, 0, + ®, sizeof(reg)); + if (!rc) + rc = fsi_slave_report_and_clear_errors(slave); + if (!rc) + return 0; + } + } + + /* getting serious, reset the slave via BREAK */ + rc = fsi_master_break(master, link); + if (rc) + return rc; + + rc = fsi_slave_set_smode(master, link, id); + if (rc) + return rc; + + return fsi_slave_report_and_clear_errors(slave); +} + int fsi_slave_read(struct fsi_slave *slave, uint32_t addr, void *val, size_t size) { uint8_t id = slave->id; - int rc; + int rc, err_rc, i; rc = fsi_slave_calc_addr(slave, &addr, &id); if (rc) return rc; - return fsi_master_read(slave->master, slave->link, id, - addr, val, size); + for (i = 0; i < slave_retries; i++) { + rc = fsi_master_read(slave->master, slave->link, + id, addr, val, size); + if (!rc) + break; + + err_rc = fsi_slave_handle_error(slave, false, addr, size); + if (err_rc) + break; + } + + return rc; } EXPORT_SYMBOL_GPL(fsi_slave_read); @@ -192,14 +287,24 @@ int fsi_slave_write(struct fsi_slave *slave, uint32_t addr, const void *val, size_t size) { uint8_t id = slave->id; - int rc; + int rc, err_rc, i; rc = fsi_slave_calc_addr(slave, &addr, &id); if (rc) return rc; - return fsi_master_write(slave->master, slave->link, id, - addr, val, size); + for (i = 0; i < slave_retries; i++) { + rc = fsi_master_write(slave->master, slave->link, + id, addr, val, size); + if (!rc) + break; + + err_rc = fsi_slave_handle_error(slave, true, addr, size); + if (err_rc) + break; + } + + return rc; } EXPORT_SYMBOL_GPL(fsi_slave_write); @@ -770,3 +875,5 @@ static void fsi_exit(void) module_init(fsi_init); module_exit(fsi_exit); +module_param(discard_errors, int, 0664); +MODULE_PARM_DESC(discard_errors, "Don't invoke error handling on bus accesses"); |