Re: [patch] ata: ahci: Enclosure Management via LED

[Kristen Carlson Accardi <kristen.c.accardi@intel.com>]

On Thu, 29 Nov 2007 09:48:02 -0800
Kristen Carlson Accardi <kristen.c.accardi@intel.com> wrote:

> This patch implements Enclosure Management via the LED protocol.  See
> the AHCI 1.1 spec for details.

Whoops, I totally messed up and sent the wrong version of this patch.
I'll send an updated one, ignore this.

Kristen


> 
> Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
> ---
> Here's a new version of the Enclosure management patch I sent a few
> weeks ago.  I tried to incorporate all the feedback, although I'm
> still checking on whether it's ok to use these capability bits on
> a 1.0 ahci device.  Please let me know if there are additional
> changes needed.
> 
>  drivers/ata/ahci.c        |  152
> ++++++++++++++++++++++++++++++++++++++++++++-
> drivers/ata/libata-scsi.c |    5 +- include/linux/libata.h    |    2 +
>  3 files changed, 155 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c
> index 2c686b4..5f22132 100644
> --- a/drivers/ata/ahci.c
> +++ b/drivers/ata/ahci.c
> @@ -44,6 +44,7 @@
>  #include <linux/dmi.h>
>  #include <scsi/scsi_host.h>
>  #include <scsi/scsi_cmnd.h>
> +#include <scsi/scsi_device.h>
>  #include <linux/libata.h>
>  
>  #define DRV_NAME	"ahci"
> @@ -92,6 +93,8 @@ enum {
>  	HOST_IRQ_STAT		= 0x08, /* interrupt status */
>  	HOST_PORTS_IMPL		= 0x0c, /* bitmap of
> implemented ports */ HOST_VERSION		= 0x10, /* AHCI
> spec. version compliancy */
> +	HOST_EM_LOC		= 0x1c, /* Enclosure Management
> location */
> +	HOST_EM_CTL		= 0x20, /* Enclosure Management
> Control */ 
>  	/* HOST_CTL bits */
>  	HOST_RESET		= (1 << 0),  /* reset controller;
> self-clear */ @@ -99,6 +102,7 @@ enum {
>  	HOST_AHCI_EN		= (1 << 31), /* AHCI enabled */
>  
>  	/* HOST_CAP bits */
> +	HOST_CAP_EMS		= (1 << 6),  /* Enclosure
> Management support */ HOST_CAP_SSC		= (1 << 14), /*
> Slumber capable */ HOST_CAP_PMP		= (1 << 17), /* Port
> Multiplier support */ HOST_CAP_CLO		= (1 << 24), /*
> Command List Override support */ @@ -193,6 +197,10 @@ enum {
>  					  ATA_FLAG_ACPI_SATA |
> ATA_FLAG_AN | ATA_FLAG_IPM,
>  	AHCI_LFLAG_COMMON		= ATA_LFLAG_SKIP_D2H_BSY,
> +
> +	/* em_ctl bits */
> +	EM_CTL_RST			= (1 << 9), /* Reset */
> +	EM_CTL_TM			= (1 << 8), /* Transmit
> Message */ };
>  
>  struct ahci_cmd_hdr {
> @@ -216,6 +224,7 @@ struct ahci_host_priv {
>  	u32			port_map;	/* port map to
> use */ u32			saved_cap;	/* saved initial
> cap */ u32			saved_port_map;	/* saved
> initial port_map */
> +	u32 			em_loc; /* enclosure management
> location */ };
>  
>  struct ahci_port_priv {
> @@ -231,6 +240,7 @@ struct ahci_port_priv {
>  	unsigned int		ncq_saw_dmas:1;
>  	unsigned int		ncq_saw_sdb:1;
>  	u32 			intr_mask;	/* interrupts
> to enable */
> +	u16			led_state;	/* saved
> current led state */ };
>  
>  static int ahci_scr_read(struct ata_port *ap, unsigned int sc_reg,
> u32 *val); @@ -572,6 +582,11 @@ static struct pci_driver
> ahci_pci_driver = { #endif
>  };
>  
> +static int ahci_em_messages = 1;
> +module_param(ahci_em_messages, int, 0444);
> +/* add other LED protocol types when they become supported */
> +MODULE_PARM_DESC(ahci_em_messages,
> +	"Set AHCI Enclosure Management Message type (0 = disabled, 1
> = LED"); 
>  static inline int ahci_nr_ports(u32 cap)
>  {
> @@ -1082,6 +1097,116 @@ static int ahci_reset_controller(struct
> ata_host *host) return 0;
>  }
>  
> +/****** LED Enclosure Management routines ********/
> +static int ahci_reset_em(struct ata_host *host)
> +{
> +	void __iomem *mmio = host->iomap[AHCI_PCI_BAR];
> +	u32 em_ctl;
> +
> +	em_ctl = readl(mmio + HOST_EM_CTL);
> +	if ((em_ctl & EM_CTL_TM) || (em_ctl & EM_CTL_RST))
> +		return -EINVAL;
> +
> +	writel(em_ctl | EM_CTL_RST, mmio + HOST_EM_CTL);
> +	return 0;
> +}
> +
> +static int ahci_transmit_led_message(struct ata_port *ap, int
> led_num,
> +			int state)
> +{
> +	struct ahci_host_priv *hpriv = ap->host->private_data;
> +	void __iomem *mmio = ap->host->iomap[AHCI_PCI_BAR];
> +	struct ahci_port_priv *pp = ap->private_data;
> +	u32 em_ctl;
> +	u32 message[] = {0, 0};
> +	unsigned int flags;
> +
> +	spin_lock_irqsave(ap->lock, flags);
> +
> +	/*
> +	 * if we are still busy transmitting a previous message,
> +	 * do not allow
> +	 */
> +	em_ctl = readl(mmio + HOST_EM_CTL);
> +	if (em_ctl & EM_CTL_TM) {
> +		spin_unlock_irqrestore(ap->lock, flags);
> +		return -EINVAL;
> +	}
> +
> +	/*
> +	 * create message header - this is all zero except for
> +	 * the message size, which is 4 bytes.
> +	 */
> +	message[0] |= (4 << 8);
> +
> +	pp->led_state &= ~(9 << (3*led_num));
> +
> +	/*
> +	 * create the actual message
> +	 * XXX will need Port Multiplier support
> +	 */
> +	message[1] = (ap->port_no | (pp->led_state << 16));
> +
> +	/* LED bit locations are determined by the led_num */
> +	message[1] |= (state << (16 + (3*led_num)));
> +
> +	/* write message to EM_LOC */
> +	writel(message[0], mmio + hpriv->em_loc);
> +	writel(message[1], mmio + hpriv->em_loc+4);
> +
> +	/* save off new led state */
> +	pp->led_state = ((message[1] >> 16) & 0x00ff);
> +
> +	/*
> +	 * tell hardware to transmit the message
> +	 */
> +	writel(em_ctl | EM_CTL_TM, mmio + HOST_EM_CTL);
> +
> +	spin_unlock_irqrestore(ap->lock, flags);
> +	return 0;
> +}
> +
> +static ssize_t ahci_led_store(struct device *dev, const char *buf,
> int num) +{
> +	struct scsi_device *sdev = to_scsi_device(dev);
> +	struct ata_port *ap = ata_shost_to_port(sdev->host);
> +	struct ata_device *atadev = ata_scsi_find_dev(ap, sdev);
> +	int state;
> +	int rc;
> +
> +	if (!atadev || !ata_dev_enabled(atadev))
> +		return -EINVAL;
> +
> +	state = simple_strtoul(buf, NULL, 0);
> +	if (state != 0 && state != 1)
> +		return -EINVAL;
> +
> +	rc = ahci_transmit_led_message(ap, num, state);
> +	if (!rc)
> +		return count;
> +	return rc;
> +}
> +
> +static ssize_t ahci_led_locate_store(struct device *dev,
> +	struct device_attribute *attr, const char *buf, size_t count)
> +{
> +	ahci_led_store(dev, buf, 1);
> +}
> +static DEVICE_ATTR(locate, S_IWUSR | S_IRUGO, NULL,
> ahci_led_locate_store); +
> +static ssize_t ahci_led_fault_store(struct device *dev,
> +	struct device_attribute *attr, const char *buf, size_t count)
> +{
> +	ahci_led_store(dev, buf, 2);
> +}
> +static DEVICE_ATTR(fault, S_IWUGO, NULL, ahci_led_fault_store);
> +
> +static struct device_attribute *ahci_em_led_attrs[] = {
> +	&dev_attr_locate,
> +	&dev_attr_fault,
> +	NULL
> +};
> +
>  static void ahci_port_init(struct pci_dev *pdev, struct ata_port *ap,
>  			   int port_no, void __iomem *mmio,
>  			   void __iomem *port_mmio)
> @@ -2178,7 +2303,8 @@ static void ahci_print_info(struct ata_host
> *host) dev_printk(KERN_INFO, &pdev->dev,
>  		"flags: "
>  		"%s%s%s%s%s%s%s"
> -		"%s%s%s%s%s%s%s\n"
> +		"%s%s%s%s%s%s%s"
> +		"%s\n"
>  		,
>  
>  		cap & (1 << 31) ? "64bit " : "",
> @@ -2195,7 +2321,8 @@ static void ahci_print_info(struct ata_host
> *host) cap & (1 << 17) ? "pmp " : "",
>  		cap & (1 << 15) ? "pio " : "",
>  		cap & (1 << 14) ? "slum " : "",
> -		cap & (1 << 13) ? "part " : ""
> +		cap & (1 << 13) ? "part " : "",
> +		cap & (1 << 6) ? "ems ": ""
>  		);
>  }
>  
> @@ -2331,6 +2458,27 @@ static int ahci_init_one(struct pci_dev *pdev,
> const struct pci_device_id *ent) ahci_init_controller(host);
>  	ahci_print_info(host);
>  
> +	if (ahci_em_messages && (hpriv->cap & HOST_CAP_EMS)) {
> +		u8 messages;
> +		void __iomem *mmio = host->iomap[AHCI_PCI_BAR];
> +		u32 em_loc = readl(mmio + HOST_EM_LOC);
> +		u32 em_ctl = readl(mmio + HOST_EM_CTL);
> +
> +		messages = (em_ctl & 0x000f0000) >> 16;
> +
> +		/* we only support LED message type right now */
> +		if ((messages & 0x01) && (ahci_em_messages == 1)) {
> +			/* store em_loc */
> +			hpriv->em_loc = ((em_loc >> 16) * 4);
> +
> +			/* reset the LEDs */
> +			ahci_reset_em(host);
> +
> +			/* modify sht to add led sysfs files */
> +			ahci_sht.sdev_attrs = ahci_em_led_attrs;
> +		}
> +	}
> +
>  	pci_set_master(pdev);
>  	return ata_host_activate(host, pdev->irq, ahci_interrupt,
> IRQF_SHARED, &ahci_sht);
> diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
> index fad236d..a49dc19 100644
> --- a/drivers/ata/libata-scsi.c
> +++ b/drivers/ata/libata-scsi.c
> @@ -55,7 +55,7 @@ typedef unsigned int (*ata_xlat_func_t)(struct
> ata_queued_cmd *qc); 
>  static struct ata_device *__ata_scsi_find_dev(struct ata_port *ap,
>  					const struct scsi_device
> *scsidev); -static struct ata_device *ata_scsi_find_dev(struct
> ata_port *ap, +struct ata_device *ata_scsi_find_dev(struct ata_port
> *ap, const struct scsi_device *scsidev);
>  static int ata_scsi_user_scan(struct Scsi_Host *shost, unsigned int
> channel, unsigned int id, unsigned int lun);
> @@ -2593,7 +2593,7 @@ static int ata_scsi_dev_enabled(struct
> ata_device *dev)
>   *	RETURNS:
>   *	Associated ATA device, or %NULL if not found.
>   */
> -static struct ata_device *
> +struct ata_device *
>  ata_scsi_find_dev(struct ata_port *ap, const struct scsi_device
> *scsidev) {
>  	struct ata_device *dev = __ata_scsi_find_dev(ap, scsidev);
> @@ -2603,6 +2603,7 @@ ata_scsi_find_dev(struct ata_port *ap, const
> struct scsi_device *scsidev) 
>  	return dev;
>  }
> +EXPORT_SYMBOL_GPL(ata_scsi_find_dev);
>  
>  /*
>   *	ata_scsi_map_proto - Map pass-thru protocol value to
> taskfile value. diff --git a/include/linux/libata.h
> b/include/linux/libata.h index ef52a07..1ccbd83 100644
> --- a/include/linux/libata.h
> +++ b/include/linux/libata.h
> @@ -900,6 +900,8 @@ extern int ata_scsi_slave_config(struct
> scsi_device *sdev); extern void ata_scsi_slave_destroy(struct
> scsi_device *sdev); extern int ata_scsi_change_queue_depth(struct
> scsi_device *sdev, int queue_depth);
> +struct ata_device *ata_scsi_find_dev(struct ata_port *ap,
> +				      const struct scsi_device
> *scsidev); extern struct ata_device *ata_dev_pair(struct ata_device
> *adev); extern int ata_do_set_mode(struct ata_link *link, struct
> ata_device **r_failed_dev); extern u8 ata_irq_on(struct ata_port *ap);