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author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/macintosh/smu.c | |
download | lwn-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz lwn-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'drivers/macintosh/smu.c')
-rw-r--r-- | drivers/macintosh/smu.c | 364 |
1 files changed, 364 insertions, 0 deletions
diff --git a/drivers/macintosh/smu.c b/drivers/macintosh/smu.c new file mode 100644 index 000000000000..fb535737d17d --- /dev/null +++ b/drivers/macintosh/smu.c @@ -0,0 +1,364 @@ +/* + * 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. + */ + +/* + * For now, this driver includes: + * - RTC get & set + * - reboot & shutdown commands + * all synchronous with IRQ disabled (ugh) + * + * TODO: + * rework in a way the PMU driver works, that is asynchronous + * with a queue of commands. I'll do that as soon as I have an + * SMU based machine at hand. Some more cleanup is needed too, + * like maybe fitting it into a platform device, etc... + * Also check what's up with cache coherency, and if we really + * can't do better than flushing the cache, maybe build a table + * of command len/reply len like the PMU driver to only flush + * what is actually necessary. + * --BenH. + */ + +#include <linux/config.h> +#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 <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 <asm/abs_addr.h> + +#define DEBUG_SMU 1 + +#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 + */ +struct smu_cmd_buf { + u8 cmd; + u8 length; + u8 data[0x0FFE]; +}; + +struct smu_device { + spinlock_t lock; + struct device_node *of_node; + int db_ack; /* doorbell ack GPIO */ + int db_req; /* doorbell req GPIO */ + u32 __iomem *db_buf; /* doorbell buffer */ + struct smu_cmd_buf *cmd_buf; /* command buffer virtual */ + u32 cmd_buf_abs; /* command buffer absolute */ +}; + +/* + * I don't think there will ever be more than one SMU, so + * for now, just hard code that + */ +static struct smu_device *smu; + +/* + * SMU low level communication stuff + */ +static inline int smu_cmd_stat(struct smu_cmd_buf *cmd_buf, u8 cmd_ack) +{ + rmb(); + return cmd_buf->cmd == cmd_ack && cmd_buf->length != 0; +} + +static inline u8 smu_save_ack_cmd(struct smu_cmd_buf *cmd_buf) +{ + return (~cmd_buf->cmd) & 0xff; +} + +static void smu_send_cmd(struct smu_device *dev) +{ + /* SMU command buf is currently cacheable, we need a physical + * address. 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(dev->cmd_buf_abs, dev->db_buf); + + /* Ring the SMU doorbell */ + pmac_do_feature_call(PMAC_FTR_WRITE_GPIO, NULL, dev->db_req, 4); + pmac_do_feature_call(PMAC_FTR_READ_GPIO, NULL, dev->db_req, 4); +} + +static int smu_cmd_done(struct smu_device *dev) +{ + unsigned long wait = 0; + int gpio; + + /* Check the SMU doorbell */ + do { + gpio = pmac_do_feature_call(PMAC_FTR_READ_GPIO, + NULL, dev->db_ack); + if ((gpio & 7) == 7) + return 0; + udelay(100); + } while(++wait < 10000); + + printk(KERN_ERR "SMU timeout !\n"); + return -ENXIO; +} + +static int smu_do_cmd(struct smu_device *dev) +{ + int rc; + u8 cmd_ack; + + DPRINTK("SMU do_cmd %02x len=%d %02x\n", + dev->cmd_buf->cmd, dev->cmd_buf->length, + dev->cmd_buf->data[0]); + + cmd_ack = smu_save_ack_cmd(dev->cmd_buf); + + /* Clear cmd_buf cache lines */ + flush_inval_dcache_range((unsigned long)dev->cmd_buf, + ((unsigned long)dev->cmd_buf) + + sizeof(struct smu_cmd_buf)); + smu_send_cmd(dev); + rc = smu_cmd_done(dev); + if (rc == 0) + rc = smu_cmd_stat(dev->cmd_buf, cmd_ack) ? 0 : -1; + + DPRINTK("SMU do_cmd %02x len=%d %02x => %d (%02x)\n", + dev->cmd_buf->cmd, dev->cmd_buf->length, + dev->cmd_buf->data[0], rc, cmd_ack); + + return rc; +} + +/* 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); +} + +#if 0 +static inline void smu_fill_set_pwrup_timer_cmd(struct smu_cmd_buf *cmd_buf) +{ + cmd_buf->cmd = 0x8e; + cmd_buf->length = 8; + cmd_buf->data[0] = 0x00; + memset(cmd_buf->data + 1, 0, 7); +} + +static inline void smu_fill_get_pwrup_timer_cmd(struct smu_cmd_buf *cmd_buf) +{ + cmd_buf->cmd = 0x8e; + cmd_buf->length = 1; + cmd_buf->data[0] = 0x01; +} + +static inline void smu_fill_dis_pwrup_timer_cmd(struct smu_cmd_buf *cmd_buf) +{ + cmd_buf->cmd = 0x8e; + cmd_buf->length = 1; + cmd_buf->data[0] = 0x02; +} +#endif + +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); +} + +static inline void smu_fill_get_rtc_cmd(struct smu_cmd_buf *cmd_buf) +{ + cmd_buf->cmd = 0x8e; + cmd_buf->length = 1; + cmd_buf->data[0] = 0x81; +} + +static void smu_parse_get_rtc_reply(struct smu_cmd_buf *cmd_buf, + struct rtc_time *time) +{ + time->tm_sec = bcd2hex(cmd_buf->data[0]); + time->tm_min = bcd2hex(cmd_buf->data[1]); + time->tm_hour = bcd2hex(cmd_buf->data[2]); + time->tm_wday = bcd2hex(cmd_buf->data[3]); + time->tm_mday = bcd2hex(cmd_buf->data[4]); + time->tm_mon = bcd2hex(cmd_buf->data[5]) - 1; + time->tm_year = bcd2hex(cmd_buf->data[6]) + 100; +} + +int smu_get_rtc_time(struct rtc_time *time) +{ + unsigned long flags; + int rc; + + if (smu == NULL) + return -ENODEV; + + memset(time, 0, sizeof(struct rtc_time)); + spin_lock_irqsave(&smu->lock, flags); + smu_fill_get_rtc_cmd(smu->cmd_buf); + rc = smu_do_cmd(smu); + if (rc == 0) + smu_parse_get_rtc_reply(smu->cmd_buf, time); + spin_unlock_irqrestore(&smu->lock, flags); + + return rc; +} + +int smu_set_rtc_time(struct rtc_time *time) +{ + unsigned long flags; + int rc; + + if (smu == NULL) + return -ENODEV; + + spin_lock_irqsave(&smu->lock, flags); + smu_fill_set_rtc_cmd(smu->cmd_buf, time); + rc = smu_do_cmd(smu); + spin_unlock_irqrestore(&smu->lock, flags); + + return rc; +} + +void smu_shutdown(void) +{ + const unsigned char *command = "SHUTDOWN"; + unsigned long flags; + + if (smu == NULL) + return; + + spin_lock_irqsave(&smu->lock, flags); + smu->cmd_buf->cmd = 0xaa; + smu->cmd_buf->length = strlen(command); + strcpy(smu->cmd_buf->data, command); + smu_do_cmd(smu); + for (;;) + ; + spin_unlock_irqrestore(&smu->lock, flags); +} + +void smu_restart(void) +{ + const unsigned char *command = "RESTART"; + unsigned long flags; + + if (smu == NULL) + return; + + spin_lock_irqsave(&smu->lock, flags); + smu->cmd_buf->cmd = 0xaa; + smu->cmd_buf->length = strlen(command); + strcpy(smu->cmd_buf->data, command); + smu_do_cmd(smu); + for (;;) + ; + spin_unlock_irqrestore(&smu->lock, flags); +} + +int smu_present(void) +{ + return smu != NULL; +} + + +int smu_init (void) +{ + struct device_node *np; + u32 *data; + + np = of_find_node_by_type(NULL, "smu"); + if (np == NULL) + return -ENODEV; + + if (smu_cmdbuf_abs == 0) { + printk(KERN_ERR "SMU: Command buffer not allocated !\n"); + return -EINVAL; + } + + smu = alloc_bootmem(sizeof(struct smu_device)); + if (smu == NULL) + return -ENOMEM; + memset(smu, 0, sizeof(*smu)); + + spin_lock_init(&smu->lock); + smu->of_node = np; + /* 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 = (struct smu_cmd_buf *)abs_to_virt(smu_cmdbuf_abs); + + np = of_find_node_by_name(NULL, "smu-doorbell"); + if (np == NULL) { + printk(KERN_ERR "SMU: Can't find doorbell GPIO !\n"); + goto fail; + } + data = (u32 *)get_property(np, "reg", NULL); + of_node_put(np); + if (data == NULL) { + printk(KERN_ERR "SMU: Can't find doorbell GPIO address !\n"); + goto fail; + } + + /* 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->db_req = 0x50 + *data; + smu->db_ack = 0x50 + *data; + + /* 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"); + goto fail; + } + + sys_ctrler = SYS_CTRLER_SMU; + return 0; + + fail: + smu = NULL; + return -ENXIO; + +} |