cregit-Linux how code gets into the kernel

Release 4.14 drivers/macintosh/smu.c

/*
 * PowerMac G5 SMU driver
 *
 * Copyright 2004 J. Mayer <l_indien@magic.fr>
 * Copyright 2005 Benjamin Herrenschmidt, IBM Corp.
 *
 * Released under the term of the GNU GPL v2.
 */

/*
 * 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/bootmem.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/memblock.h>
#include <linux/sched/signal.h>

#include <asm/byteorder.h>
#include <asm/io.h>
#include <asm/prom.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(unsigned long data);

/*
 * 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_inval_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); }

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Benjamin Herrenschmidt18799.47%480.00%
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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_inval_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; }

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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; }

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Benjamin Herrenschmidt24100.00%1100.00%
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/* * 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; }

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Benjamin Herrenschmidt11099.10%266.67%
Michael Ellerman10.90%133.33%
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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); }

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Benjamin Herrenschmidt182100.00%1100.00%
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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); }

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EXPORT_SYMBOL(smu_poll);
void smu_done_complete(struct smu_cmd *cmd, void *misc) { struct completion *comp = misc; complete(comp); }

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EXPORT_SYMBOL(smu_done_complete);
void smu_spinwait_cmd(struct smu_cmd *cmd) { while(cmd->status == 1) smu_poll(); }

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Benjamin Herrenschmidt21100.00%1100.00%
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EXPORT_SYMBOL(smu_spinwait_cmd); /* RTC low level commands */
static inline int bcd2hex (int n) { return (((n & 0xf0) >> 4) * 10) + (n & 0xf); }

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static inline int hex2bcd (int n) { return ((n / 10) << 4) + (n % 10); }

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Benjamin Herrenschmidt27100.00%1100.00%
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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); }

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Benjamin Herrenschmidt137100.00%1100.00%
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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; }

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Benjamin Herrenschmidt179100.00%1100.00%
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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; }

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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 (;;) ; }

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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 (;;) ; }

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Benjamin Herrenschmidt63100.00%1100.00%
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int smu_present(void) { return smu != NULL; }

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Benjamin Herrenschmidt12100.00%1100.00%
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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_alloc_base(4096, 4096, 0x80000000UL); if (smu_cmdbuf_abs == 0) { printk(KERN_ERR "SMU: Command buffer allocation failed !\n"); ret = -EINVAL; goto fail_np; } smu = alloc_bootmem(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: free_bootmem(__pa(smu), sizeof(struct smu_device)); smu = NULL; fail_np: of_node_put(np); return ret; }

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Benjamin Herrenschmidt37283.04%545.45%
Julia Lawall6714.96%19.09%
JoonSoo Kim30.67%19.09%
Michael Ellerman30.67%218.18%
Stephen Rothwell20.45%19.09%
Jeremy Kerr10.22%19.09%
Total448100.00%11100.00%


static int smu_late_init(void) { if (!smu) return 0; init_timer(&smu->i2c_timer); smu->i2c_timer.function = smu_i2c_retry; smu->i2c_timer.data = (unsigned long)smu; 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; }

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Thomas Gleixner20.91%116.67%
Rob Herring20.91%116.67%
Total220100.00%6100.00%

/* 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 (np = NULL; (np = of_get_next_child(smu->of_node, np)) != NULL;) if (of_device_is_compatible(np, "smu-sensors")) of_platform_device_create(np, "smu-sensors", &smu->of_dev->dev); }

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Benjamin Herrenschmidt5895.08%250.00%
David Howells23.28%125.00%
Stephen Rothwell11.64%125.00%
Total61100.00%4100.00%

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; }

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Benjamin Herrenschmidt3597.22%150.00%
Grant C. Likely12.78%150.00%
Total36100.00%2100.00%

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; }

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Benjamin Herrenschmidt1789.47%133.33%
Kay Sievers15.26%133.33%
Grant C. Likely15.26%133.33%
Total19100.00%3100.00%

device_initcall(smu_init_sysfs);
struct platform_device *smu_get_ofdev(void) { if (!smu) return NULL; return smu->of_dev; }

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Total22100.00%2100.00%

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); }

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static void smu_i2c_retry(unsigned long data) { 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); }

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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(0); 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); }

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Benjamin Herrenschmidt266100.00%3100.00%
Total266100.00%3100.00%


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: memset(&cmd->info.sublen, 0, 4); break; case SMU_I2C_TRANSFER_COMBINED: cmd->info.devaddr &= 0xfe; 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; }

Contributors

PersonTokensPropCommitsCommitProp
Benjamin Herrenschmidt423100.00%2100.00%
Total423100.00%2100.00%

/* * 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 = &comp; params[0] = SMU_CMD_MISC_ee_GET_DATABLOCK_REC; params[1] = 0x4; *((u32 *)&params[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; }

Contributors

PersonTokensPropCommitsCommitProp
Benjamin Herrenschmidt21499.53%375.00%
Peter Zijlstra10.47%125.00%
Total215100.00%4100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
Benjamin Herrenschmidt31899.07%240.00%
Robert P. J. Day10.31%120.00%
Peter Zijlstra10.31%120.00%
Nathan Fontenot10.31%120.00%
Total321100.00%5100.00%

/* Note: Only allowed to return error code in pointers (using ERR_PTR) * when interruptible is 1 */
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; }

Contributors

PersonTokensPropCommitsCommitProp
Benjamin Herrenschmidt14295.95%240.00%
Ingo Molnar32.03%120.00%
Jeremy Kerr21.35%120.00%
Stephen Rothwell10.68%120.00%
Total148100.00%5100.00%


const struct smu_sdbp_header *smu_get_sdb_partition(int id, unsigned int *size) { return __smu_get_sdb_partition(id, size, 0); }

Contributors

PersonTokensPropCommitsCommitProp
Benjamin Herrenschmidt2596.15%150.00%
Jeremy Kerr13.85%150.00%
Total26100.00%2100.00%

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 == 0) 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; }

Contributors

PersonTokensPropCommitsCommitProp
Benjamin Herrenschmidt10588.98%125.00%
Arnd Bergmann1210.17%250.00%
Yoann Padioleau10.85%125.00%
Total118100.00%4100.00%


static void smu_user_cmd_done(struct smu_cmd *cmd, void *misc) { struct smu_private *pp = misc; wake_up_all(&pp->wait); }

Contributors

PersonTokensPropCommitsCommitProp
Benjamin Herrenschmidt30100.00%1100.00%
Total30100.00%1100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
Benjamin Herrenschmidt36599.73%375.00%
Jeremy Kerr10.27%125.00%
Total366100.00%4100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
Benjamin Herrenschmidt33596.54%266.67%
Julia Lawall123.46%133.33%
Total347100.00%3100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
Benjamin Herrenschmidt33100.00%2100.00%
Total33100.00%2100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
Benjamin Herrenschmidt76100.00%2100.00%
Total76100.00%2100.00%


static unsigned int smu_fpoll(struct file *file, poll_table *wait) { struct smu_private *pp = file->private_data; unsigned int mask = 0; unsigned long flags; if (pp == 0) 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 |= POLLIN; spin_unlock_irqrestore(&pp->lock, flags); } if (pp->mode == smu_file_events) { /* Not yet implemented */ } return mask; }

Contributors

PersonTokensPropCommitsCommitProp
Benjamin Herrenschmidt118100.00%2100.00%
Total118100.00%2100.00%


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 == 0) 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; }

Contributors

PersonTokensPropCommitsCommitProp
Benjamin Herrenschmidt20699.04%266.67%
Andrew Morton20.96%133.33%
Total208100.00%3100.00%

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; }

Contributors

PersonTokensPropCommitsCommitProp
Benjamin Herrenschmidt36100.00%2100.00%
Total36100.00%2100.00%

device_initcall(smu_device_init);

Overall Contributors

PersonTokensPropCommitsCommitProp
Benjamin Herrenschmidt572697.07%1125.00%
Julia Lawall791.34%24.55%
Arnd Bergmann180.31%24.55%
Stephen Rothwell130.22%36.82%
Grant C. Likely110.19%36.82%
Ingo Molnar100.17%24.55%
Michael Ellerman80.14%24.55%
Jeremy Kerr50.08%12.27%
Rob Herring50.08%24.55%
Tejun Heo30.05%12.27%
JoonSoo Kim30.05%12.27%
Peter Zijlstra20.03%12.27%
David Howells20.03%12.27%
Andrew Morton20.03%12.27%
Thomas Gleixner20.03%12.27%
Arjan van de Ven10.02%12.27%
Paulius Zaleckas10.02%12.27%
Andy Shevchenko10.02%12.27%
Robert P. J. Day10.02%12.27%
Kay Sievers10.02%12.27%
Yoann Padioleau10.02%12.27%
Linus Torvalds10.02%12.27%
Márton Németh10.02%12.27%
Nathan Fontenot10.02%12.27%
Joe Perches10.02%12.27%
Total5899100.00%44100.00%
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