[POWERPC] Xserve cpu-meter driver (3e00a5ae) · Commits · e / devices / android_kernel_teracube_2e

drivers/macintosh/Kconfig

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Original line number	Diff line number	Diff line
		@@ -228,4 +228,11 @@ config ANSLCD
		tristate "Support for ANS LCD display"
		depends on ADB_CUDA && PPC_PMAC

		config PMAC_RACKMETER
		tristate "Support for Apple XServe front panel LEDs"
		depends on PPC_PMAC
		help
		This driver procides some support to control the front panel
		blue LEDs "vu-meter" of the XServer macs.

		endmenu

drivers/macintosh/Makefile

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Original line number	Diff line number	Diff line
		@@ -42,3 +42,4 @@ obj-$(CONFIG_WINDFARM_PM112) += windfarm_pm112.o windfarm_smu_sat.o \
		windfarm_smu_sensors.o \
		windfarm_max6690_sensor.o \
		windfarm_lm75_sensor.o windfarm_pid.o
		obj-$(CONFIG_PMAC_RACKMETER) += rack-meter.o

drivers/macintosh/rack-meter.c

0 → 100644

+612 −0

Original line number	Diff line number	Diff line
		/*
		* RackMac vu-meter driver
		*
		* (c) Copyright 2006 Benjamin Herrenschmidt, IBM Corp.
		* <benh@kernel.crashing.org>
		*
		* Released under the term of the GNU GPL v2.
		*
		* Support the CPU-meter LEDs of the Xserve G5
		*
		* TODO: Implement PWM to do variable intensity and provide userland
		* interface for fun. Also, the CPU-meter could be made nicer by being
		* a bit less "immediate" but giving instead a more average load over
		* time. Patches welcome :-)
		*
		*/
		#undef DEBUG

		#include <linux/types.h>
		#include <linux/kernel.h>
		#include <linux/device.h>
		#include <linux/interrupt.h>
		#include <linux/module.h>
		#include <linux/pci.h>
		#include <linux/dma-mapping.h>
		#include <linux/kernel_stat.h>

		#include <asm/io.h>
		#include <asm/prom.h>
		#include <asm/machdep.h>
		#include <asm/pmac_feature.h>
		#include <asm/dbdma.h>
		#include <asm/dbdma.h>
		#include <asm/macio.h>
		#include <asm/keylargo.h>

		/* Number of samples in a sample buffer */
		#define SAMPLE_COUNT 256

		/* CPU meter sampling rate in ms */
		#define CPU_SAMPLING_RATE 250

		struct rackmeter_dma {
		struct dbdma_cmd cmd[4] ____cacheline_aligned;
		u32 mark ____cacheline_aligned;
		u32 buf1[SAMPLE_COUNT] ____cacheline_aligned;
		u32 buf2[SAMPLE_COUNT] ____cacheline_aligned;
		} ____cacheline_aligned;

		struct rackmeter_cpu {
		struct work_struct sniffer;
		cputime64_t prev_wall;
		cputime64_t prev_idle;
		int zero;
		} ____cacheline_aligned;

		struct rackmeter {
		struct macio_dev *mdev;
		unsigned int irq;
		struct device_node *i2s;
		u8 *ubuf;
		struct dbdma_regs __iomem *dma_regs;
		void __iomem *i2s_regs;
		dma_addr_t dma_buf_p;
		struct rackmeter_dma *dma_buf_v;
		int stale_irq;
		struct rackmeter_cpu cpu[2];
		int paused;
		struct mutex sem;
		};

		/* To be set as a tunable */
		static int rackmeter_ignore_nice;

		/* This GPIO is whacked by the OS X driver when initializing */
		#define RACKMETER_MAGIC_GPIO 0x78

		/* This is copied from cpufreq_ondemand, maybe we should put it in
		* a common header somewhere
		*/
		static inline cputime64_t get_cpu_idle_time(unsigned int cpu)
		{
		cputime64_t retval;

		retval = cputime64_add(kstat_cpu(cpu).cpustat.idle,
		kstat_cpu(cpu).cpustat.iowait);

		if (rackmeter_ignore_nice)
		retval = cputime64_add(retval, kstat_cpu(cpu).cpustat.nice);

		return retval;
		}

		static void rackmeter_setup_i2s(struct rackmeter *rm)
		{
		struct macio_chip *macio = rm->mdev->bus->chip;

		/* First whack magic GPIO */
		pmac_call_feature(PMAC_FTR_WRITE_GPIO, NULL, RACKMETER_MAGIC_GPIO, 5);


		/* Call feature code to enable the sound channel and the proper
		* clock sources
		*/
		pmac_call_feature(PMAC_FTR_SOUND_CHIP_ENABLE, rm->i2s, 0, 1);

		/* Power i2s and stop i2s clock. We whack MacIO FCRs directly for now.
		* This is a bit racy, thus we should add new platform functions to
		* handle that. snd-aoa needs that too
		*/
		MACIO_BIS(KEYLARGO_FCR1, KL1_I2S0_ENABLE);
		MACIO_BIC(KEYLARGO_FCR1, KL1_I2S0_CLK_ENABLE_BIT);
		(void)MACIO_IN32(KEYLARGO_FCR1);
		udelay(10);

		/* Then setup i2s. For now, we use the same magic value that
		* the OS X driver seems to use. We might want to play around
		* with the clock divisors later
		*/
		out_le32(rm->i2s_regs + 0x10, 0x01fa0000);
		(void)in_le32(rm->i2s_regs + 0x10);
		udelay(10);

		/* Fully restart i2s*/
		MACIO_BIS(KEYLARGO_FCR1, KL1_I2S0_CELL_ENABLE \|
		KL1_I2S0_CLK_ENABLE_BIT);
		(void)MACIO_IN32(KEYLARGO_FCR1);
		udelay(10);
		}

		static void rackmeter_set_default_pattern(struct rackmeter *rm)
		{
		int i;

		for (i = 0; i < 16; i++) {
		if (i < 8)
		rm->ubuf[i] = (i & 1) * 255;
		else
		rm->ubuf[i] = ((~i) & 1) * 255;
		}
		}

		static void rackmeter_do_pause(struct rackmeter *rm, int pause)
		{
		struct rackmeter_dma *rdma = rm->dma_buf_v;

		pr_debug("rackmeter: %s\n", pause ? "paused" : "started");

		rm->paused = pause;
		if (pause) {
		DBDMA_DO_STOP(rm->dma_regs);
		return;
		}
		memset(rdma->buf1, 0, SAMPLE_COUNT & sizeof(u32));
		memset(rdma->buf2, 0, SAMPLE_COUNT & sizeof(u32));

		rm->dma_buf_v->mark = 0;

		mb();
		out_le32(&rm->dma_regs->cmdptr_hi, 0);
		out_le32(&rm->dma_regs->cmdptr, rm->dma_buf_p);
		out_le32(&rm->dma_regs->control, (RUN << 16) \| RUN);
		}

		static void rackmeter_setup_dbdma(struct rackmeter *rm)
		{
		struct rackmeter_dma *db = rm->dma_buf_v;
		struct dbdma_cmd *cmd = db->cmd;

		/* Make sure dbdma is reset */
		DBDMA_DO_RESET(rm->dma_regs);

		pr_debug("rackmeter: mark offset=0x%lx\n",
		offsetof(struct rackmeter_dma, mark));
		pr_debug("rackmeter: buf1 offset=0x%lx\n",
		offsetof(struct rackmeter_dma, buf1));
		pr_debug("rackmeter: buf2 offset=0x%lx\n",
		offsetof(struct rackmeter_dma, buf2));

		/* Prepare 4 dbdma commands for the 2 buffers */
		memset(cmd, 0, 4 * sizeof(struct dbdma_cmd));
		st_le16(&cmd->req_count, 4);
		st_le16(&cmd->command, STORE_WORD \| INTR_ALWAYS \| KEY_SYSTEM);
		st_le32(&cmd->phy_addr, rm->dma_buf_p +
		offsetof(struct rackmeter_dma, mark));
		st_le32(&cmd->cmd_dep, 0x02000000);
		cmd++;

		st_le16(&cmd->req_count, SAMPLE_COUNT * 4);
		st_le16(&cmd->command, OUTPUT_MORE);
		st_le32(&cmd->phy_addr, rm->dma_buf_p +
		offsetof(struct rackmeter_dma, buf1));
		cmd++;

		st_le16(&cmd->req_count, 4);
		st_le16(&cmd->command, STORE_WORD \| INTR_ALWAYS \| KEY_SYSTEM);
		st_le32(&cmd->phy_addr, rm->dma_buf_p +
		offsetof(struct rackmeter_dma, mark));
		st_le32(&cmd->cmd_dep, 0x01000000);
		cmd++;

		st_le16(&cmd->req_count, SAMPLE_COUNT * 4);
		st_le16(&cmd->command, OUTPUT_MORE \| BR_ALWAYS);
		st_le32(&cmd->phy_addr, rm->dma_buf_p +
		offsetof(struct rackmeter_dma, buf2));
		st_le32(&cmd->cmd_dep, rm->dma_buf_p);

		rackmeter_do_pause(rm, 0);
		}

		static void rackmeter_do_timer(void *data)
		{
		struct rackmeter *rm = data;
		unsigned int cpu = smp_processor_id();
		struct rackmeter_cpu *rcpu = &rm->cpu[cpu];
		cputime64_t cur_jiffies, total_idle_ticks;
		unsigned int total_ticks, idle_ticks;
		int i, offset, load, cumm, pause;

		cur_jiffies = jiffies64_to_cputime64(get_jiffies_64());
		total_ticks = (unsigned int)cputime64_sub(cur_jiffies,
		rcpu->prev_wall);
		rcpu->prev_wall = cur_jiffies;

		total_idle_ticks = get_cpu_idle_time(cpu);
		idle_ticks = (unsigned int) cputime64_sub(total_idle_ticks,
		rcpu->prev_idle);
		rcpu->prev_idle = total_idle_ticks;

		/* We do a very dumb calculation to update the LEDs for now,
		* we'll do better once we have actual PWM implemented
		*/
		load = (9 * (total_ticks - idle_ticks)) / total_ticks;

		offset = cpu << 3;
		cumm = 0;
		for (i = 0; i < 8; i++) {
		u8 ub = (load > i) ? 0xff : 0;
		rm->ubuf[i + offset] = ub;
		cumm \|= ub;
		}
		rcpu->zero = (cumm == 0);

		/* Now check if LEDs are all 0, we can stop DMA */
		pause = (rm->cpu[0].zero && rm->cpu[1].zero);
		if (pause != rm->paused) {
		mutex_lock(&rm->sem);
		pause = (rm->cpu[0].zero && rm->cpu[1].zero);
		rackmeter_do_pause(rm, pause);
		mutex_unlock(&rm->sem);
		}
		schedule_delayed_work_on(cpu, &rcpu->sniffer,
		msecs_to_jiffies(CPU_SAMPLING_RATE));
		}

		static void __devinit rackmeter_init_cpu_sniffer(struct rackmeter *rm)
		{
		unsigned int cpu;

		/* This driver works only with 1 or 2 CPUs numbered 0 and 1,
		* but that's really all we have on Apple Xserve. It doesn't
		* play very nice with CPU hotplug neither but we don't do that
		* on those machines yet
		*/

		INIT_WORK(&rm->cpu[0].sniffer, rackmeter_do_timer, rm);
		INIT_WORK(&rm->cpu[1].sniffer, rackmeter_do_timer, rm);

		for_each_online_cpu(cpu) {
		struct rackmeter_cpu *rcpu;

		if (cpu > 1)
		continue;
		rcpu = &rm->cpu[cpu];;
		rcpu->prev_idle = get_cpu_idle_time(cpu);
		rcpu->prev_wall = jiffies64_to_cputime64(get_jiffies_64());
		schedule_delayed_work_on(cpu, &rm->cpu[cpu].sniffer,
		msecs_to_jiffies(CPU_SAMPLING_RATE));
		}
		}

		static void __devexit rackmeter_stop_cpu_sniffer(struct rackmeter *rm)
		{
		cancel_rearming_delayed_work(&rm->cpu[0].sniffer);
		cancel_rearming_delayed_work(&rm->cpu[1].sniffer);
		}

		static int rackmeter_setup(struct rackmeter *rm)
		{
		pr_debug("rackmeter: setting up i2s..\n");
		rackmeter_setup_i2s(rm);

		pr_debug("rackmeter: setting up default pattern..\n");
		rackmeter_set_default_pattern(rm);

		pr_debug("rackmeter: setting up dbdma..\n");
		rackmeter_setup_dbdma(rm);

		pr_debug("rackmeter: start CPU measurements..\n");
		rackmeter_init_cpu_sniffer(rm);

		printk(KERN_INFO "RackMeter initialized\n");

		return 0;
		}

		/* XXX FIXME: No PWM yet, this is 0/1 */
		static u32 rackmeter_calc_sample(struct rackmeter *rm, unsigned int index)
		{
		int led;
		u32 sample = 0;

		for (led = 0; led < 16; led++) {
		sample >>= 1;
		sample \|= ((rm->ubuf[led] >= 0x80) << 15);
		}
		return (sample << 17) \| (sample >> 15);
		}

		static irqreturn_t rackmeter_irq(int irq, void *arg)
		{
		struct rackmeter *rm = arg;
		struct rackmeter_dma *db = rm->dma_buf_v;
		unsigned int mark, i;
		u32 *buf;

		/* Flush PCI buffers with an MMIO read. Maybe we could actually
		* check the status one day ... in case things go wrong, though
		* this never happened to me
		*/
		(void)in_le32(&rm->dma_regs->status);

		/* Make sure the CPU gets us in order */
		rmb();

		/* Read mark */
		mark = db->mark;
		if (mark != 1 && mark != 2) {
		printk(KERN_WARNING "rackmeter: Incorrect DMA mark 0x%08x\n",
		mark);
		/* We allow for 3 errors like that (stale DBDMA irqs) */
		if (++rm->stale_irq > 3) {
		printk(KERN_ERR "rackmeter: Too many errors,"
		" stopping DMA\n");
		DBDMA_DO_RESET(rm->dma_regs);
		}
		return IRQ_HANDLED;
		}

		/* Next buffer we need to fill is mark value */
		buf = mark == 1 ? db->buf1 : db->buf2;

		/* Fill it now. This routine converts the 8 bits depth sample array
		* into the PWM bitmap for each LED.
		*/
		for (i = 0; i < SAMPLE_COUNT; i++)
		buf[i] = rackmeter_calc_sample(rm, i);


		return IRQ_HANDLED;
		}

		static int __devinit rackmeter_probe(struct macio_dev* mdev,
		const struct of_device_id *match)
		{
		struct device_node i2s = NULL, np = NULL;
		struct rackmeter *rm = NULL;
		struct resource ri2s, rdma;
		int rc = -ENODEV;

		pr_debug("rackmeter_probe()\n");

		/* Get i2s-a node */
		while ((i2s = of_get_next_child(mdev->ofdev.node, i2s)) != NULL)
		if (strcmp(i2s->name, "i2s-a") == 0)
		break;
		if (i2s == NULL) {
		pr_debug(" i2s-a child not found\n");
		goto bail;
		}
		/* Get lightshow or virtual sound */
		while ((np = of_get_next_child(i2s, np)) != NULL) {
		if (strcmp(np->name, "lightshow") == 0)
		break;
		if ((strcmp(np->name, "sound") == 0) &&
		get_property(np, "virtual", NULL) != NULL)
		break;
		}
		if (np == NULL) {
		pr_debug(" lightshow or sound+virtual child not found\n");
		goto bail;
		}

		/* Create and initialize our instance data */
		rm = kzalloc(sizeof(struct rackmeter), GFP_KERNEL);
		if (rm == NULL) {
		printk(KERN_ERR "rackmeter: failed to allocate memory !\n");
		rc = -ENOMEM;
		goto bail_release;
		}
		rm->mdev = mdev;
		rm->i2s = i2s;
		mutex_init(&rm->sem);
		dev_set_drvdata(&mdev->ofdev.dev, rm);
		/* Check resources availability. We need at least resource 0 and 1 */
		#if 0 /* Use that when i2s-a is finally an mdev per-se */
		if (macio_resource_count(mdev) < 2 \|\| macio_irq_count(mdev) < 2) {
		printk(KERN_ERR
		"rackmeter: found match but lacks resources: %s"
		" (%d resources, %d interrupts)\n",
		mdev->ofdev.node->full_name);
		rc = -ENXIO;
		goto bail_free;
		}
		if (macio_request_resources(mdev, "rackmeter")) {
		printk(KERN_ERR
		"rackmeter: failed to request resources: %s\n",
		mdev->ofdev.node->full_name);
		rc = -EBUSY;
		goto bail_free;
		}
		rm->irq = macio_irq(mdev, 1);
		#else
		rm->irq = irq_of_parse_and_map(i2s, 1);
		if (rm->irq == NO_IRQ \|\|
		of_address_to_resource(i2s, 0, &ri2s) \|\|
		of_address_to_resource(i2s, 1, &rdma)) {
		printk(KERN_ERR
		"rackmeter: found match but lacks resources: %s",
		mdev->ofdev.node->full_name);
		rc = -ENXIO;
		goto bail_free;
		}
		#endif

		pr_debug(" i2s @0x%08x\n", (unsigned int)ri2s.start);
		pr_debug(" dma @0x%08x\n", (unsigned int)rdma.start);
		pr_debug(" irq %d\n", rm->irq);

		rm->ubuf = (u8 *)__get_free_page(GFP_KERNEL);
		if (rm->ubuf == NULL) {
		printk(KERN_ERR
		"rackmeter: failed to allocate samples page !\n");
		rc = -ENOMEM;
		goto bail_release;
		}

		rm->dma_buf_v = dma_alloc_coherent(&macio_get_pci_dev(mdev)->dev,
		sizeof(struct rackmeter_dma),
		&rm->dma_buf_p, GFP_KERNEL);
		if (rm->dma_buf_v == NULL) {
		printk(KERN_ERR
		"rackmeter: failed to allocate dma buffer !\n");
		rc = -ENOMEM;
		goto bail_free_samples;
		}
		#if 0
		rm->i2s_regs = ioremap(macio_resource_start(mdev, 0), 0x1000);
		#else
		rm->i2s_regs = ioremap(ri2s.start, 0x1000);
		#endif
		if (rm->i2s_regs == NULL) {
		printk(KERN_ERR
		"rackmeter: failed to map i2s registers !\n");
		rc = -ENXIO;
		goto bail_free_dma;
		}
		#if 0
		rm->dma_regs = ioremap(macio_resource_start(mdev, 1), 0x100);
		#else
		rm->dma_regs = ioremap(rdma.start, 0x100);
		#endif
		if (rm->dma_regs == NULL) {
		printk(KERN_ERR
		"rackmeter: failed to map dma registers !\n");
		rc = -ENXIO;
		goto bail_unmap_i2s;
		}

		rc = rackmeter_setup(rm);
		if (rc) {
		printk(KERN_ERR
		"rackmeter: failed to initialize !\n");
		rc = -ENXIO;
		goto bail_unmap_dma;
		}

		rc = request_irq(rm->irq, rackmeter_irq, 0, "rackmeter", rm);
		if (rc != 0) {
		printk(KERN_ERR
		"rackmeter: failed to request interrupt !\n");
		goto bail_stop_dma;
		}
		of_node_put(np);
		return 0;

		bail_stop_dma:
		DBDMA_DO_RESET(rm->dma_regs);
		bail_unmap_dma:
		iounmap(rm->dma_regs);
		bail_unmap_i2s:
		iounmap(rm->i2s_regs);
		bail_free_dma:
		dma_free_coherent(&macio_get_pci_dev(mdev)->dev,
		sizeof(struct rackmeter_dma),
		rm->dma_buf_v, rm->dma_buf_p);
		bail_free_samples:
		free_page((unsigned long)rm->ubuf);
		bail_release:
		#if 0
		macio_release_resources(mdev);
		#endif
		bail_free:
		kfree(rm);
		bail:
		of_node_put(i2s);
		of_node_put(np);
		dev_set_drvdata(&mdev->ofdev.dev, NULL);
		return rc;
		}

		static int __devexit rackmeter_remove(struct macio_dev* mdev)
		{
		struct rackmeter *rm = dev_get_drvdata(&mdev->ofdev.dev);

		/* Stop CPU sniffer timer & work queues */
		rackmeter_stop_cpu_sniffer(rm);

		/* Clear reference to private data */
		dev_set_drvdata(&mdev->ofdev.dev, NULL);

		/* Stop/reset dbdma */
		DBDMA_DO_RESET(rm->dma_regs);

		/* Release the IRQ */
		free_irq(rm->irq, rm);

		/* Unmap registers */
		iounmap(rm->dma_regs);
		iounmap(rm->i2s_regs);

		/* Free DMA */
		dma_free_coherent(&macio_get_pci_dev(mdev)->dev,
		sizeof(struct rackmeter_dma),
		rm->dma_buf_v, rm->dma_buf_p);

		/* Free samples */
		free_page((unsigned long)rm->ubuf);

		#if 0
		/* Release resources */
		macio_release_resources(mdev);
		#endif

		/* Get rid of me */
		kfree(rm);

		return 0;
		}

		static int rackmeter_shutdown(struct macio_dev* mdev)
		{
		struct rackmeter *rm = dev_get_drvdata(&mdev->ofdev.dev);

		if (rm == NULL)
		return -ENODEV;

		/* Stop CPU sniffer timer & work queues */
		rackmeter_stop_cpu_sniffer(rm);

		/* Stop/reset dbdma */
		DBDMA_DO_RESET(rm->dma_regs);

		return 0;
		}

		static struct of_device_id rackmeter_match[] = {
		{ .name = "i2s" },
		{ }
		};

		static struct macio_driver rackmeter_drv = {
		.name = "rackmeter",
		.owner = THIS_MODULE,
		.match_table = rackmeter_match,
		.probe = rackmeter_probe,
		.remove = rackmeter_remove,
		.shutdown = rackmeter_shutdown,
		};


		static int __init rackmeter_init(void)
		{
		pr_debug("rackmeter_init()\n");

		return macio_register_driver(&rackmeter_drv);
		}

		static void __exit rackmeter_exit(void)
		{
		pr_debug("rackmeter_exit()\n");

		macio_unregister_driver(&rackmeter_drv);
		}

		module_init(rackmeter_init);
		module_exit(rackmeter_exit);


		MODULE_LICENSE("GPL");
		MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
		MODULE_DESCRIPTION("RackMeter: Support vu-meter on XServe front panel");

include/asm-powerpc/dbdma.h

+7 −1

Original line number	Diff line number	Diff line
		@@ -98,5 +98,11 @@ struct dbdma_cmd {
		; \
		} while(0)

		#define DBDMA_DO_RESET(regs) do { \
		out_le32(&((regs)->control), (ACTIVE\|DEAD\|WAKE\|FLUSH\|PAUSE\|RUN)<<16);\
		while(in_le32(&((regs)->status)) & (RUN)) \
		; \
		} while(0)

		#endif /* _ASM_DBDMA_H_ */
		#endif /* __KERNEL__ */