diff options
Diffstat (limited to 'drivers/macintosh/smu.c')
| -rw-r--r-- | drivers/macintosh/smu.c | 1337 |
1 files changed, 1337 insertions, 0 deletions
diff --git a/drivers/macintosh/smu.c b/drivers/macintosh/smu.c new file mode 100644 index 000000000..b495bfa77 --- /dev/null +++ b/drivers/macintosh/smu.c @@ -0,0 +1,1337 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * PowerMac G5 SMU driver + * + * Copyright 2004 J. Mayer <l_indien@magic.fr> + * Copyright 2005 Benjamin Herrenschmidt, IBM Corp. + */ + +/* + * TODO: + * - maybe add timeout to commands ? + * - blocking version of time functions + * - polling version of i2c commands (including timer that works with + * interrupts off) + * - maybe avoid some data copies with i2c by directly using the smu cmd + * buffer and a lower level internal interface + * - understand SMU -> CPU events and implement reception of them via + * the userland interface + */ + +#include <linux/types.h> +#include <linux/kernel.h> +#include <linux/device.h> +#include <linux/dmapool.h> +#include <linux/memblock.h> +#include <linux/vmalloc.h> +#include <linux/highmem.h> +#include <linux/jiffies.h> +#include <linux/interrupt.h> +#include <linux/rtc.h> +#include <linux/completion.h> +#include <linux/miscdevice.h> +#include <linux/delay.h> +#include <linux/poll.h> +#include <linux/mutex.h> +#include <linux/of_device.h> +#include <linux/of_irq.h> +#include <linux/of_platform.h> +#include <linux/slab.h> +#include <linux/sched/signal.h> + +#include <asm/byteorder.h> +#include <asm/io.h> +#include <asm/machdep.h> +#include <asm/pmac_feature.h> +#include <asm/smu.h> +#include <asm/sections.h> +#include <linux/uaccess.h> + +#define VERSION "0.7" +#define AUTHOR "(c) 2005 Benjamin Herrenschmidt, IBM Corp." + +#undef DEBUG_SMU + +#ifdef DEBUG_SMU +#define DPRINTK(fmt, args...) do { printk(KERN_DEBUG fmt , ##args); } while (0) +#else +#define DPRINTK(fmt, args...) do { } while (0) +#endif + +/* + * This is the command buffer passed to the SMU hardware + */ +#define SMU_MAX_DATA 254 + +struct smu_cmd_buf { + u8 cmd; + u8 length; + u8 data[SMU_MAX_DATA]; +}; + +struct smu_device { + spinlock_t lock; + struct device_node *of_node; + struct platform_device *of_dev; + int doorbell; /* doorbell gpio */ + u32 __iomem *db_buf; /* doorbell buffer */ + struct device_node *db_node; + unsigned int db_irq; + int msg; + struct device_node *msg_node; + unsigned int msg_irq; + struct smu_cmd_buf *cmd_buf; /* command buffer virtual */ + u32 cmd_buf_abs; /* command buffer absolute */ + struct list_head cmd_list; + struct smu_cmd *cmd_cur; /* pending command */ + int broken_nap; + struct list_head cmd_i2c_list; + struct smu_i2c_cmd *cmd_i2c_cur; /* pending i2c command */ + struct timer_list i2c_timer; +}; + +/* + * I don't think there will ever be more than one SMU, so + * for now, just hard code that + */ +static DEFINE_MUTEX(smu_mutex); +static struct smu_device *smu; +static DEFINE_MUTEX(smu_part_access); +static int smu_irq_inited; +static unsigned long smu_cmdbuf_abs; + +static void smu_i2c_retry(struct timer_list *t); + +/* + * SMU driver low level stuff + */ + +static void smu_start_cmd(void) +{ + unsigned long faddr, fend; + struct smu_cmd *cmd; + + if (list_empty(&smu->cmd_list)) + return; + + /* Fetch first command in queue */ + cmd = list_entry(smu->cmd_list.next, struct smu_cmd, link); + smu->cmd_cur = cmd; + list_del(&cmd->link); + + DPRINTK("SMU: starting cmd %x, %d bytes data\n", cmd->cmd, + cmd->data_len); + DPRINTK("SMU: data buffer: %8ph\n", cmd->data_buf); + + /* Fill the SMU command buffer */ + smu->cmd_buf->cmd = cmd->cmd; + smu->cmd_buf->length = cmd->data_len; + memcpy(smu->cmd_buf->data, cmd->data_buf, cmd->data_len); + + /* Flush command and data to RAM */ + faddr = (unsigned long)smu->cmd_buf; + fend = faddr + smu->cmd_buf->length + 2; + flush_dcache_range(faddr, fend); + + + /* We also disable NAP mode for the duration of the command + * on U3 based machines. + * This is slightly racy as it can be written back to 1 by a sysctl + * but that never happens in practice. There seem to be an issue with + * U3 based machines such as the iMac G5 where napping for the + * whole duration of the command prevents the SMU from fetching it + * from memory. This might be related to the strange i2c based + * mechanism the SMU uses to access memory. + */ + if (smu->broken_nap) + powersave_nap = 0; + + /* This isn't exactly a DMA mapping here, I suspect + * the SMU is actually communicating with us via i2c to the + * northbridge or the CPU to access RAM. + */ + writel(smu->cmd_buf_abs, smu->db_buf); + + /* Ring the SMU doorbell */ + pmac_do_feature_call(PMAC_FTR_WRITE_GPIO, NULL, smu->doorbell, 4); +} + + +static irqreturn_t smu_db_intr(int irq, void *arg) +{ + unsigned long flags; + struct smu_cmd *cmd; + void (*done)(struct smu_cmd *cmd, void *misc) = NULL; + void *misc = NULL; + u8 gpio; + int rc = 0; + + /* SMU completed the command, well, we hope, let's make sure + * of it + */ + spin_lock_irqsave(&smu->lock, flags); + + gpio = pmac_do_feature_call(PMAC_FTR_READ_GPIO, NULL, smu->doorbell); + if ((gpio & 7) != 7) { + spin_unlock_irqrestore(&smu->lock, flags); + return IRQ_HANDLED; + } + + cmd = smu->cmd_cur; + smu->cmd_cur = NULL; + if (cmd == NULL) + goto bail; + + if (rc == 0) { + unsigned long faddr; + int reply_len; + u8 ack; + + /* CPU might have brought back the cache line, so we need + * to flush again before peeking at the SMU response. We + * flush the entire buffer for now as we haven't read the + * reply length (it's only 2 cache lines anyway) + */ + faddr = (unsigned long)smu->cmd_buf; + flush_dcache_range(faddr, faddr + 256); + + /* Now check ack */ + ack = (~cmd->cmd) & 0xff; + if (ack != smu->cmd_buf->cmd) { + DPRINTK("SMU: incorrect ack, want %x got %x\n", + ack, smu->cmd_buf->cmd); + rc = -EIO; + } + reply_len = rc == 0 ? smu->cmd_buf->length : 0; + DPRINTK("SMU: reply len: %d\n", reply_len); + if (reply_len > cmd->reply_len) { + printk(KERN_WARNING "SMU: reply buffer too small," + "got %d bytes for a %d bytes buffer\n", + reply_len, cmd->reply_len); + reply_len = cmd->reply_len; + } + cmd->reply_len = reply_len; + if (cmd->reply_buf && reply_len) + memcpy(cmd->reply_buf, smu->cmd_buf->data, reply_len); + } + + /* Now complete the command. Write status last in order as we lost + * ownership of the command structure as soon as it's no longer -1 + */ + done = cmd->done; + misc = cmd->misc; + mb(); + cmd->status = rc; + + /* Re-enable NAP mode */ + if (smu->broken_nap) + powersave_nap = 1; + bail: + /* Start next command if any */ + smu_start_cmd(); + spin_unlock_irqrestore(&smu->lock, flags); + + /* Call command completion handler if any */ + if (done) + done(cmd, misc); + + /* It's an edge interrupt, nothing to do */ + return IRQ_HANDLED; +} + + +static irqreturn_t smu_msg_intr(int irq, void *arg) +{ + /* I don't quite know what to do with this one, we seem to never + * receive it, so I suspect we have to arm it someway in the SMU + * to start getting events that way. + */ + + printk(KERN_INFO "SMU: message interrupt !\n"); + + /* It's an edge interrupt, nothing to do */ + return IRQ_HANDLED; +} + + +/* + * Queued command management. + * + */ + +int smu_queue_cmd(struct smu_cmd *cmd) +{ + unsigned long flags; + + if (smu == NULL) + return -ENODEV; + if (cmd->data_len > SMU_MAX_DATA || + cmd->reply_len > SMU_MAX_DATA) + return -EINVAL; + + cmd->status = 1; + spin_lock_irqsave(&smu->lock, flags); + list_add_tail(&cmd->link, &smu->cmd_list); + if (smu->cmd_cur == NULL) + smu_start_cmd(); + spin_unlock_irqrestore(&smu->lock, flags); + + /* Workaround for early calls when irq isn't available */ + if (!smu_irq_inited || !smu->db_irq) + smu_spinwait_cmd(cmd); + + return 0; +} +EXPORT_SYMBOL(smu_queue_cmd); + + +int smu_queue_simple(struct smu_simple_cmd *scmd, u8 command, + unsigned int data_len, + void (*done)(struct smu_cmd *cmd, void *misc), + void *misc, ...) +{ + struct smu_cmd *cmd = &scmd->cmd; + va_list list; + int i; + + if (data_len > sizeof(scmd->buffer)) + return -EINVAL; + + memset(scmd, 0, sizeof(*scmd)); + cmd->cmd = command; + cmd->data_len = data_len; + cmd->data_buf = scmd->buffer; + cmd->reply_len = sizeof(scmd->buffer); + cmd->reply_buf = scmd->buffer; + cmd->done = done; + cmd->misc = misc; + + va_start(list, misc); + for (i = 0; i < data_len; ++i) + scmd->buffer[i] = (u8)va_arg(list, int); + va_end(list); + + return smu_queue_cmd(cmd); +} +EXPORT_SYMBOL(smu_queue_simple); + + +void smu_poll(void) +{ + u8 gpio; + + if (smu == NULL) + return; + + gpio = pmac_do_feature_call(PMAC_FTR_READ_GPIO, NULL, smu->doorbell); + if ((gpio & 7) == 7) + smu_db_intr(smu->db_irq, smu); +} +EXPORT_SYMBOL(smu_poll); + + +void smu_done_complete(struct smu_cmd *cmd, void *misc) +{ + struct completion *comp = misc; + + complete(comp); +} +EXPORT_SYMBOL(smu_done_complete); + + +void smu_spinwait_cmd(struct smu_cmd *cmd) +{ + while(cmd->status == 1) + smu_poll(); +} +EXPORT_SYMBOL(smu_spinwait_cmd); + + +/* RTC low level commands */ +static inline int bcd2hex (int n) +{ + return (((n & 0xf0) >> 4) * 10) + (n & 0xf); +} + + +static inline int hex2bcd (int n) +{ + return ((n / 10) << 4) + (n % 10); +} + + +static inline void smu_fill_set_rtc_cmd(struct smu_cmd_buf *cmd_buf, + struct rtc_time *time) +{ + cmd_buf->cmd = 0x8e; + cmd_buf->length = 8; + cmd_buf->data[0] = 0x80; + cmd_buf->data[1] = hex2bcd(time->tm_sec); + cmd_buf->data[2] = hex2bcd(time->tm_min); + cmd_buf->data[3] = hex2bcd(time->tm_hour); + cmd_buf->data[4] = time->tm_wday; + cmd_buf->data[5] = hex2bcd(time->tm_mday); + cmd_buf->data[6] = hex2bcd(time->tm_mon) + 1; + cmd_buf->data[7] = hex2bcd(time->tm_year - 100); +} + + +int smu_get_rtc_time(struct rtc_time *time, int spinwait) +{ + struct smu_simple_cmd cmd; + int rc; + + if (smu == NULL) + return -ENODEV; + + memset(time, 0, sizeof(struct rtc_time)); + rc = smu_queue_simple(&cmd, SMU_CMD_RTC_COMMAND, 1, NULL, NULL, + SMU_CMD_RTC_GET_DATETIME); + if (rc) + return rc; + smu_spinwait_simple(&cmd); + + time->tm_sec = bcd2hex(cmd.buffer[0]); + time->tm_min = bcd2hex(cmd.buffer[1]); + time->tm_hour = bcd2hex(cmd.buffer[2]); + time->tm_wday = bcd2hex(cmd.buffer[3]); + time->tm_mday = bcd2hex(cmd.buffer[4]); + time->tm_mon = bcd2hex(cmd.buffer[5]) - 1; + time->tm_year = bcd2hex(cmd.buffer[6]) + 100; + + return 0; +} + + +int smu_set_rtc_time(struct rtc_time *time, int spinwait) +{ + struct smu_simple_cmd cmd; + int rc; + + if (smu == NULL) + return -ENODEV; + + rc = smu_queue_simple(&cmd, SMU_CMD_RTC_COMMAND, 8, NULL, NULL, + SMU_CMD_RTC_SET_DATETIME, + hex2bcd(time->tm_sec), + hex2bcd(time->tm_min), + hex2bcd(time->tm_hour), + time->tm_wday, + hex2bcd(time->tm_mday), + hex2bcd(time->tm_mon) + 1, + hex2bcd(time->tm_year - 100)); + if (rc) + return rc; + smu_spinwait_simple(&cmd); + + return 0; +} + + +void smu_shutdown(void) +{ + struct smu_simple_cmd cmd; + + if (smu == NULL) + return; + + if (smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 9, NULL, NULL, + 'S', 'H', 'U', 'T', 'D', 'O', 'W', 'N', 0)) + return; + smu_spinwait_simple(&cmd); + for (;;) + ; +} + + +void smu_restart(void) +{ + struct smu_simple_cmd cmd; + + if (smu == NULL) + return; + + if (smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 8, NULL, NULL, + 'R', 'E', 'S', 'T', 'A', 'R', 'T', 0)) + return; + smu_spinwait_simple(&cmd); + for (;;) + ; +} + + +int smu_present(void) +{ + return smu != NULL; +} +EXPORT_SYMBOL(smu_present); + + +int __init smu_init (void) +{ + struct device_node *np; + const u32 *data; + int ret = 0; + + np = of_find_node_by_type(NULL, "smu"); + if (np == NULL) + return -ENODEV; + + printk(KERN_INFO "SMU: Driver %s %s\n", VERSION, AUTHOR); + + /* + * SMU based G5s need some memory below 2Gb. Thankfully this is + * called at a time where memblock is still available. + */ + smu_cmdbuf_abs = memblock_phys_alloc_range(4096, 4096, 0, 0x80000000UL); + if (smu_cmdbuf_abs == 0) { + printk(KERN_ERR "SMU: Command buffer allocation failed !\n"); + ret = -EINVAL; + goto fail_np; + } + + smu = memblock_alloc(sizeof(struct smu_device), SMP_CACHE_BYTES); + if (!smu) + panic("%s: Failed to allocate %zu bytes\n", __func__, + sizeof(struct smu_device)); + + spin_lock_init(&smu->lock); + INIT_LIST_HEAD(&smu->cmd_list); + INIT_LIST_HEAD(&smu->cmd_i2c_list); + smu->of_node = np; + smu->db_irq = 0; + smu->msg_irq = 0; + + /* smu_cmdbuf_abs is in the low 2G of RAM, can be converted to a + * 32 bits value safely + */ + smu->cmd_buf_abs = (u32)smu_cmdbuf_abs; + smu->cmd_buf = __va(smu_cmdbuf_abs); + + smu->db_node = of_find_node_by_name(NULL, "smu-doorbell"); + if (smu->db_node == NULL) { + printk(KERN_ERR "SMU: Can't find doorbell GPIO !\n"); + ret = -ENXIO; + goto fail_bootmem; + } + data = of_get_property(smu->db_node, "reg", NULL); + if (data == NULL) { + printk(KERN_ERR "SMU: Can't find doorbell GPIO address !\n"); + ret = -ENXIO; + goto fail_db_node; + } + + /* Current setup has one doorbell GPIO that does both doorbell + * and ack. GPIOs are at 0x50, best would be to find that out + * in the device-tree though. + */ + smu->doorbell = *data; + if (smu->doorbell < 0x50) + smu->doorbell += 0x50; + + /* Now look for the smu-interrupt GPIO */ + do { + smu->msg_node = of_find_node_by_name(NULL, "smu-interrupt"); + if (smu->msg_node == NULL) + break; + data = of_get_property(smu->msg_node, "reg", NULL); + if (data == NULL) { + of_node_put(smu->msg_node); + smu->msg_node = NULL; + break; + } + smu->msg = *data; + if (smu->msg < 0x50) + smu->msg += 0x50; + } while(0); + + /* Doorbell buffer is currently hard-coded, I didn't find a proper + * device-tree entry giving the address. Best would probably to use + * an offset for K2 base though, but let's do it that way for now. + */ + smu->db_buf = ioremap(0x8000860c, 0x1000); + if (smu->db_buf == NULL) { + printk(KERN_ERR "SMU: Can't map doorbell buffer pointer !\n"); + ret = -ENXIO; + goto fail_msg_node; + } + + /* U3 has an issue with NAP mode when issuing SMU commands */ + smu->broken_nap = pmac_get_uninorth_variant() < 4; + if (smu->broken_nap) + printk(KERN_INFO "SMU: using NAP mode workaround\n"); + + sys_ctrler = SYS_CTRLER_SMU; + return 0; + +fail_msg_node: + of_node_put(smu->msg_node); +fail_db_node: + of_node_put(smu->db_node); +fail_bootmem: + memblock_free(smu, sizeof(struct smu_device)); + smu = NULL; +fail_np: + of_node_put(np); + return ret; +} + + +static int smu_late_init(void) +{ + if (!smu) + return 0; + + timer_setup(&smu->i2c_timer, smu_i2c_retry, 0); + + if (smu->db_node) { + smu->db_irq = irq_of_parse_and_map(smu->db_node, 0); + if (!smu->db_irq) + printk(KERN_ERR "smu: failed to map irq for node %pOF\n", + smu->db_node); + } + if (smu->msg_node) { + smu->msg_irq = irq_of_parse_and_map(smu->msg_node, 0); + if (!smu->msg_irq) + printk(KERN_ERR "smu: failed to map irq for node %pOF\n", + smu->msg_node); + } + + /* + * Try to request the interrupts + */ + + if (smu->db_irq) { + if (request_irq(smu->db_irq, smu_db_intr, + IRQF_SHARED, "SMU doorbell", smu) < 0) { + printk(KERN_WARNING "SMU: can't " + "request interrupt %d\n", + smu->db_irq); + smu->db_irq = 0; + } + } + + if (smu->msg_irq) { + if (request_irq(smu->msg_irq, smu_msg_intr, + IRQF_SHARED, "SMU message", smu) < 0) { + printk(KERN_WARNING "SMU: can't " + "request interrupt %d\n", + smu->msg_irq); + smu->msg_irq = 0; + } + } + + smu_irq_inited = 1; + return 0; +} +/* This has to be before arch_initcall as the low i2c stuff relies on the + * above having been done before we reach arch_initcalls + */ +core_initcall(smu_late_init); + +/* + * sysfs visibility + */ + +static void smu_expose_childs(struct work_struct *unused) +{ + struct device_node *np; + + for_each_child_of_node(smu->of_node, np) + if (of_device_is_compatible(np, "smu-sensors")) + of_platform_device_create(np, "smu-sensors", + &smu->of_dev->dev); +} + +static DECLARE_WORK(smu_expose_childs_work, smu_expose_childs); + +static int smu_platform_probe(struct platform_device* dev) +{ + if (!smu) + return -ENODEV; + smu->of_dev = dev; + + /* + * Ok, we are matched, now expose all i2c busses. We have to defer + * that unfortunately or it would deadlock inside the device model + */ + schedule_work(&smu_expose_childs_work); + + return 0; +} + +static const struct of_device_id smu_platform_match[] = +{ + { + .type = "smu", + }, + {}, +}; + +static struct platform_driver smu_of_platform_driver = +{ + .driver = { + .name = "smu", + .of_match_table = smu_platform_match, + }, + .probe = smu_platform_probe, +}; + +static int __init smu_init_sysfs(void) +{ + /* + * For now, we don't power manage machines with an SMU chip, + * I'm a bit too far from figuring out how that works with those + * new chipsets, but that will come back and bite us + */ + platform_driver_register(&smu_of_platform_driver); + return 0; +} + +device_initcall(smu_init_sysfs); + +struct platform_device *smu_get_ofdev(void) +{ + if (!smu) + return NULL; + return smu->of_dev; +} + +EXPORT_SYMBOL_GPL(smu_get_ofdev); + +/* + * i2c interface + */ + +static void smu_i2c_complete_command(struct smu_i2c_cmd *cmd, int fail) +{ + void (*done)(struct smu_i2c_cmd *cmd, void *misc) = cmd->done; + void *misc = cmd->misc; + unsigned long flags; + + /* Check for read case */ + if (!fail && cmd->read) { + if (cmd->pdata[0] < 1) + fail = 1; + else + memcpy(cmd->info.data, &cmd->pdata[1], + cmd->info.datalen); + } + + DPRINTK("SMU: completing, success: %d\n", !fail); + + /* Update status and mark no pending i2c command with lock + * held so nobody comes in while we dequeue an eventual + * pending next i2c command + */ + spin_lock_irqsave(&smu->lock, flags); + smu->cmd_i2c_cur = NULL; + wmb(); + cmd->status = fail ? -EIO : 0; + + /* Is there another i2c command waiting ? */ + if (!list_empty(&smu->cmd_i2c_list)) { + struct smu_i2c_cmd *newcmd; + + /* Fetch it, new current, remove from list */ + newcmd = list_entry(smu->cmd_i2c_list.next, + struct smu_i2c_cmd, link); + smu->cmd_i2c_cur = newcmd; + list_del(&cmd->link); + + /* Queue with low level smu */ + list_add_tail(&cmd->scmd.link, &smu->cmd_list); + if (smu->cmd_cur == NULL) + smu_start_cmd(); + } + spin_unlock_irqrestore(&smu->lock, flags); + + /* Call command completion handler if any */ + if (done) + done(cmd, misc); + +} + + +static void smu_i2c_retry(struct timer_list *unused) +{ + struct smu_i2c_cmd *cmd = smu->cmd_i2c_cur; + + DPRINTK("SMU: i2c failure, requeuing...\n"); + + /* requeue command simply by resetting reply_len */ + cmd->pdata[0] = 0xff; + cmd->scmd.reply_len = sizeof(cmd->pdata); + smu_queue_cmd(&cmd->scmd); +} + + +static void smu_i2c_low_completion(struct smu_cmd *scmd, void *misc) +{ + struct smu_i2c_cmd *cmd = misc; + int fail = 0; + + DPRINTK("SMU: i2c compl. stage=%d status=%x pdata[0]=%x rlen: %x\n", + cmd->stage, scmd->status, cmd->pdata[0], scmd->reply_len); + + /* Check for possible status */ + if (scmd->status < 0) + fail = 1; + else if (cmd->read) { + if (cmd->stage == 0) + fail = cmd->pdata[0] != 0; + else + fail = cmd->pdata[0] >= 0x80; + } else { + fail = cmd->pdata[0] != 0; + } + + /* Handle failures by requeuing command, after 5ms interval + */ + if (fail && --cmd->retries > 0) { + DPRINTK("SMU: i2c failure, starting timer...\n"); + BUG_ON(cmd != smu->cmd_i2c_cur); + if (!smu_irq_inited) { + mdelay(5); + smu_i2c_retry(NULL); + return; + } + mod_timer(&smu->i2c_timer, jiffies + msecs_to_jiffies(5)); + return; + } + + /* If failure or stage 1, command is complete */ + if (fail || cmd->stage != 0) { + smu_i2c_complete_command(cmd, fail); + return; + } + + DPRINTK("SMU: going to stage 1\n"); + + /* Ok, initial command complete, now poll status */ + scmd->reply_buf = cmd->pdata; + scmd->reply_len = sizeof(cmd->pdata); + scmd->data_buf = cmd->pdata; + scmd->data_len = 1; + cmd->pdata[0] = 0; + cmd->stage = 1; + cmd->retries = 20; + smu_queue_cmd(scmd); +} + + +int smu_queue_i2c(struct smu_i2c_cmd *cmd) +{ + unsigned long flags; + + if (smu == NULL) + return -ENODEV; + + /* Fill most fields of scmd */ + cmd->scmd.cmd = SMU_CMD_I2C_COMMAND; + cmd->scmd.done = smu_i2c_low_completion; + cmd->scmd.misc = cmd; + cmd->scmd.reply_buf = cmd->pdata; + cmd->scmd.reply_len = sizeof(cmd->pdata); + cmd->scmd.data_buf = (u8 *)(char *)&cmd->info; + cmd->scmd.status = 1; + cmd->stage = 0; + cmd->pdata[0] = 0xff; + cmd->retries = 20; + cmd->status = 1; + + /* Check transfer type, sanitize some "info" fields + * based on transfer type and do more checking + */ + cmd->info.caddr = cmd->info.devaddr; + cmd->read = cmd->info.devaddr & 0x01; + switch(cmd->info.type) { + case SMU_I2C_TRANSFER_SIMPLE: + cmd->info.sublen = 0; + memset(cmd->info.subaddr, 0, sizeof(cmd->info.subaddr)); + break; + case SMU_I2C_TRANSFER_COMBINED: + cmd->info.devaddr &= 0xfe; + fallthrough; + case SMU_I2C_TRANSFER_STDSUB: + if (cmd->info.sublen > 3) + return -EINVAL; + break; + default: + return -EINVAL; + } + + /* Finish setting up command based on transfer direction + */ + if (cmd->read) { + if (cmd->info.datalen > SMU_I2C_READ_MAX) + return -EINVAL; + memset(cmd->info.data, 0xff, cmd->info.datalen); + cmd->scmd.data_len = 9; + } else { + if (cmd->info.datalen > SMU_I2C_WRITE_MAX) + return -EINVAL; + cmd->scmd.data_len = 9 + cmd->info.datalen; + } + + DPRINTK("SMU: i2c enqueuing command\n"); + DPRINTK("SMU: %s, len=%d bus=%x addr=%x sub0=%x type=%x\n", + cmd->read ? "read" : "write", cmd->info.datalen, + cmd->info.bus, cmd->info.caddr, + cmd->info.subaddr[0], cmd->info.type); + + + /* Enqueue command in i2c list, and if empty, enqueue also in + * main command list + */ + spin_lock_irqsave(&smu->lock, flags); + if (smu->cmd_i2c_cur == NULL) { + smu->cmd_i2c_cur = cmd; + list_add_tail(&cmd->scmd.link, &smu->cmd_list); + if (smu->cmd_cur == NULL) + smu_start_cmd(); + } else + list_add_tail(&cmd->link, &smu->cmd_i2c_list); + spin_unlock_irqrestore(&smu->lock, flags); + + return 0; +} + +/* + * Handling of "partitions" + */ + +static int smu_read_datablock(u8 *dest, unsigned int addr, unsigned int len) +{ + DECLARE_COMPLETION_ONSTACK(comp); + unsigned int chunk; + struct smu_cmd cmd; + int rc; + u8 params[8]; + + /* We currently use a chunk size of 0xe. We could check the + * SMU firmware version and use bigger sizes though + */ + chunk = 0xe; + + while (len) { + unsigned int clen = min(len, chunk); + + cmd.cmd = SMU_CMD_MISC_ee_COMMAND; + cmd.data_len = 7; + cmd.data_buf = params; + cmd.reply_len = chunk; + cmd.reply_buf = dest; + cmd.done = smu_done_complete; + cmd.misc = ∁ + params[0] = SMU_CMD_MISC_ee_GET_DATABLOCK_REC; + params[1] = 0x4; + *((u32 *)¶ms[2]) = addr; + params[6] = clen; + + rc = smu_queue_cmd(&cmd); + if (rc) + return rc; + wait_for_completion(&comp); + if (cmd.status != 0) + return rc; + if (cmd.reply_len != clen) { + printk(KERN_DEBUG "SMU: short read in " + "smu_read_datablock, got: %d, want: %d\n", + cmd.reply_len, clen); + return -EIO; + } + len -= clen; + addr += clen; + dest += clen; + } + return 0; +} + +static struct smu_sdbp_header *smu_create_sdb_partition(int id) +{ + DECLARE_COMPLETION_ONSTACK(comp); + struct smu_simple_cmd cmd; + unsigned int addr, len, tlen; + struct smu_sdbp_header *hdr; + struct property *prop; + + /* First query the partition info */ + DPRINTK("SMU: Query partition infos ... (irq=%d)\n", smu->db_irq); + smu_queue_simple(&cmd, SMU_CMD_PARTITION_COMMAND, 2, + smu_done_complete, &comp, + SMU_CMD_PARTITION_LATEST, id); + wait_for_completion(&comp); + DPRINTK("SMU: done, status: %d, reply_len: %d\n", + cmd.cmd.status, cmd.cmd.reply_len); + + /* Partition doesn't exist (or other error) */ + if (cmd.cmd.status != 0 || cmd.cmd.reply_len != 6) + return NULL; + + /* Fetch address and length from reply */ + addr = *((u16 *)cmd.buffer); + len = cmd.buffer[3] << 2; + /* Calucluate total length to allocate, including the 17 bytes + * for "sdb-partition-XX" that we append at the end of the buffer + */ + tlen = sizeof(struct property) + len + 18; + + prop = kzalloc(tlen, GFP_KERNEL); + if (prop == NULL) + return NULL; + hdr = (struct smu_sdbp_header *)(prop + 1); + prop->name = ((char *)prop) + tlen - 18; + sprintf(prop->name, "sdb-partition-%02x", id); + prop->length = len; + prop->value = hdr; + prop->next = NULL; + + /* Read the datablock */ + if (smu_read_datablock((u8 *)hdr, addr, len)) { + printk(KERN_DEBUG "SMU: datablock read failed while reading " + "partition %02x !\n", id); + goto failure; + } + + /* Got it, check a few things and create the property */ + if (hdr->id != id) { + printk(KERN_DEBUG "SMU: Reading partition %02x and got " + "%02x !\n", id, hdr->id); + goto failure; + } + if (of_add_property(smu->of_node, prop)) { + printk(KERN_DEBUG "SMU: Failed creating sdb-partition-%02x " + "property !\n", id); + goto failure; + } + + return hdr; + failure: + kfree(prop); + return NULL; +} + +/* Note: Only allowed to return error code in pointers (using ERR_PTR) + * when interruptible is 1 + */ +static const struct smu_sdbp_header *__smu_get_sdb_partition(int id, + unsigned int *size, int interruptible) +{ + char pname[32]; + const struct smu_sdbp_header *part; + + if (!smu) + return NULL; + + sprintf(pname, "sdb-partition-%02x", id); + + DPRINTK("smu_get_sdb_partition(%02x)\n", id); + + if (interruptible) { + int rc; + rc = mutex_lock_interruptible(&smu_part_access); + if (rc) + return ERR_PTR(rc); + } else + mutex_lock(&smu_part_access); + + part = of_get_property(smu->of_node, pname, size); + if (part == NULL) { + DPRINTK("trying to extract from SMU ...\n"); + part = smu_create_sdb_partition(id); + if (part != NULL && size) + *size = part->len << 2; + } + mutex_unlock(&smu_part_access); + return part; +} + +const struct smu_sdbp_header *smu_get_sdb_partition(int id, unsigned int *size) +{ + return __smu_get_sdb_partition(id, size, 0); +} +EXPORT_SYMBOL(smu_get_sdb_partition); + + +/* + * Userland driver interface + */ + + +static LIST_HEAD(smu_clist); +static DEFINE_SPINLOCK(smu_clist_lock); + +enum smu_file_mode { + smu_file_commands, + smu_file_events, + smu_file_closing +}; + +struct smu_private +{ + struct list_head list; + enum smu_file_mode mode; + int busy; + struct smu_cmd cmd; + spinlock_t lock; + wait_queue_head_t wait; + u8 buffer[SMU_MAX_DATA]; +}; + + +static int smu_open(struct inode *inode, struct file *file) +{ + struct smu_private *pp; + unsigned long flags; + + pp = kzalloc(sizeof(struct smu_private), GFP_KERNEL); + if (!pp) + return -ENOMEM; + spin_lock_init(&pp->lock); + pp->mode = smu_file_commands; + init_waitqueue_head(&pp->wait); + + mutex_lock(&smu_mutex); + spin_lock_irqsave(&smu_clist_lock, flags); + list_add(&pp->list, &smu_clist); + spin_unlock_irqrestore(&smu_clist_lock, flags); + file->private_data = pp; + mutex_unlock(&smu_mutex); + + return 0; +} + + +static void smu_user_cmd_done(struct smu_cmd *cmd, void *misc) +{ + struct smu_private *pp = misc; + + wake_up_all(&pp->wait); +} + + +static ssize_t smu_write(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + struct smu_private *pp = file->private_data; + unsigned long flags; + struct smu_user_cmd_hdr hdr; + int rc = 0; + + if (pp->busy) + return -EBUSY; + else if (copy_from_user(&hdr, buf, sizeof(hdr))) + return -EFAULT; + else if (hdr.cmdtype == SMU_CMDTYPE_WANTS_EVENTS) { + pp->mode = smu_file_events; + return 0; + } else if (hdr.cmdtype == SMU_CMDTYPE_GET_PARTITION) { + const struct smu_sdbp_header *part; + part = __smu_get_sdb_partition(hdr.cmd, NULL, 1); + if (part == NULL) + return -EINVAL; + else if (IS_ERR(part)) + return PTR_ERR(part); + return 0; + } else if (hdr.cmdtype != SMU_CMDTYPE_SMU) + return -EINVAL; + else if (pp->mode != smu_file_commands) + return -EBADFD; + else if (hdr.data_len > SMU_MAX_DATA) + return -EINVAL; + + spin_lock_irqsave(&pp->lock, flags); + if (pp->busy) { + spin_unlock_irqrestore(&pp->lock, flags); + return -EBUSY; + } + pp->busy = 1; + pp->cmd.status = 1; + spin_unlock_irqrestore(&pp->lock, flags); + + if (copy_from_user(pp->buffer, buf + sizeof(hdr), hdr.data_len)) { + pp->busy = 0; + return -EFAULT; + } + + pp->cmd.cmd = hdr.cmd; + pp->cmd.data_len = hdr.data_len; + pp->cmd.reply_len = SMU_MAX_DATA; + pp->cmd.data_buf = pp->buffer; + pp->cmd.reply_buf = pp->buffer; + pp->cmd.done = smu_user_cmd_done; + pp->cmd.misc = pp; + rc = smu_queue_cmd(&pp->cmd); + if (rc < 0) + return rc; + return count; +} + + +static ssize_t smu_read_command(struct file *file, struct smu_private *pp, + char __user *buf, size_t count) +{ + DECLARE_WAITQUEUE(wait, current); + struct smu_user_reply_hdr hdr; + unsigned long flags; + int size, rc = 0; + + if (!pp->busy) + return 0; + if (count < sizeof(struct smu_user_reply_hdr)) + return -EOVERFLOW; + spin_lock_irqsave(&pp->lock, flags); + if (pp->cmd.status == 1) { + if (file->f_flags & O_NONBLOCK) { + spin_unlock_irqrestore(&pp->lock, flags); + return -EAGAIN; + } + add_wait_queue(&pp->wait, &wait); + for (;;) { + set_current_state(TASK_INTERRUPTIBLE); + rc = 0; + if (pp->cmd.status != 1) + break; + rc = -ERESTARTSYS; + if (signal_pending(current)) + break; + spin_unlock_irqrestore(&pp->lock, flags); + schedule(); + spin_lock_irqsave(&pp->lock, flags); + } + set_current_state(TASK_RUNNING); + remove_wait_queue(&pp->wait, &wait); + } + spin_unlock_irqrestore(&pp->lock, flags); + if (rc) + return rc; + if (pp->cmd.status != 0) + pp->cmd.reply_len = 0; + size = sizeof(hdr) + pp->cmd.reply_len; + if (count < size) + size = count; + rc = size; + hdr.status = pp->cmd.status; + hdr.reply_len = pp->cmd.reply_len; + if (copy_to_user(buf, &hdr, sizeof(hdr))) + return -EFAULT; + size -= sizeof(hdr); + if (size && copy_to_user(buf + sizeof(hdr), pp->buffer, size)) + return -EFAULT; + pp->busy = 0; + + return rc; +} + + +static ssize_t smu_read_events(struct file *file, struct smu_private *pp, + char __user *buf, size_t count) +{ + /* Not implemented */ + msleep_interruptible(1000); + return 0; +} + + +static ssize_t smu_read(struct file *file, char __user *buf, + size_t count, loff_t *ppos) +{ + struct smu_private *pp = file->private_data; + + if (pp->mode == smu_file_commands) + return smu_read_command(file, pp, buf, count); + if (pp->mode == smu_file_events) + return smu_read_events(file, pp, buf, count); + + return -EBADFD; +} + +static __poll_t smu_fpoll(struct file *file, poll_table *wait) +{ + struct smu_private *pp = file->private_data; + __poll_t mask = 0; + unsigned long flags; + + if (!pp) + return 0; + + if (pp->mode == smu_file_commands) { + poll_wait(file, &pp->wait, wait); + + spin_lock_irqsave(&pp->lock, flags); + if (pp->busy && pp->cmd.status != 1) + mask |= EPOLLIN; + spin_unlock_irqrestore(&pp->lock, flags); + } + if (pp->mode == smu_file_events) { + /* Not yet implemented */ + } + return mask; +} + +static int smu_release(struct inode *inode, struct file *file) +{ + struct smu_private *pp = file->private_data; + unsigned long flags; + unsigned int busy; + + if (!pp) + return 0; + + file->private_data = NULL; + + /* Mark file as closing to avoid races with new request */ + spin_lock_irqsave(&pp->lock, flags); + pp->mode = smu_file_closing; + busy = pp->busy; + + /* Wait for any pending request to complete */ + if (busy && pp->cmd.status == 1) { + DECLARE_WAITQUEUE(wait, current); + + add_wait_queue(&pp->wait, &wait); + for (;;) { + set_current_state(TASK_UNINTERRUPTIBLE); + if (pp->cmd.status != 1) + break; + spin_unlock_irqrestore(&pp->lock, flags); + schedule(); + spin_lock_irqsave(&pp->lock, flags); + } + set_current_state(TASK_RUNNING); + remove_wait_queue(&pp->wait, &wait); + } + spin_unlock_irqrestore(&pp->lock, flags); + + spin_lock_irqsave(&smu_clist_lock, flags); + list_del(&pp->list); + spin_unlock_irqrestore(&smu_clist_lock, flags); + kfree(pp); + + return 0; +} + + +static const struct file_operations smu_device_fops = { + .llseek = no_llseek, + .read = smu_read, + .write = smu_write, + .poll = smu_fpoll, + .open = smu_open, + .release = smu_release, +}; + +static struct miscdevice pmu_device = { + MISC_DYNAMIC_MINOR, "smu", &smu_device_fops +}; + +static int smu_device_init(void) +{ + if (!smu) + return -ENODEV; + if (misc_register(&pmu_device) < 0) + printk(KERN_ERR "via-pmu: cannot register misc device.\n"); + return 0; +} +device_initcall(smu_device_init); |