Commit 8ec6552f authored by Dan Williams's avatar Dan Williams Committed by James Bottomley
Browse files

[SCSI] libsas: sgpio write support 



Add SFF-8485 v0.7 / SAS-1 smp-write-gpio register support to libsas.
Defer SAS-2 support unless/until it defines an sgpio interface.

Minimum implementation needed to get the lights blinking.
try_test_sas_gpio_gp_bit() provides a common method to parse the
incoming write data (raw bitstream), and the to_sas_gpio_gp_bit() helper
routine can be used as a basis for the set/clear operations for the
'read' implementation.  Host implementations parse as many bits
(ODx.[012]) as are locally supported and report the number of registers
successfully written.  If the submitted data overruns the internal
number of registers available report the write as a success with the
number of bytes remaining reported in ->resid_len.

Example (assuming an active backplane) set the "identify" pattern for
the first 21 devices:

smp_write_gpio --count=2 --data=92,49,24,92,24,92,49,24 -t 4 --index=1 /dev/bsg/sas_hostX

Signed-off-by: default avatarDan Williams <dan.j.williams@intel.com>
Signed-off-by: default avatarJames Bottomley <JBottomley@Parallels.com>
parent 9c224ac2

drivers/scsi/libsas/sas_host_smp.c

+101 −2
Original line number Diff line number Diff line
@@ -51,6 +51,91 @@ static void sas_host_smp_discover(struct sas_ha_struct *sas_ha, u8 *resp_data, 
	resp_data[15] = rphy->identify.target_port_protocols;

}



/**

 * to_sas_gpio_gp_bit - given the gpio frame data find the byte/bit position of 'od'

 * @od: od bit to find

 * @data: incoming bitstream (from frame)

 * @index: requested data register index (from frame)

 * @count: total number of registers in the bitstream (from frame)

 * @bit: bit position of 'od' in the returned byte

 *

 * returns NULL if 'od' is not in 'data'

 *

 * From SFF-8485 v0.7:

 * "In GPIO_TX[1], bit 0 of byte 3 contains the first bit (i.e., OD0.0)

 *  and bit 7 of byte 0 contains the 32nd bit (i.e., OD10.1).

 *

 *  In GPIO_TX[2], bit 0 of byte 3 contains the 33rd bit (i.e., OD10.2)

 *  and bit 7 of byte 0 contains the 64th bit (i.e., OD21.0)."

 *

 * The general-purpose (raw-bitstream) RX registers have the same layout

 * although 'od' is renamed 'id' for 'input data'.

 *

 * SFF-8489 defines the behavior of the LEDs in response to the 'od' values.

 */

static u8 *to_sas_gpio_gp_bit(unsigned int od, u8 *data, u8 index, u8 count, u8 *bit)

{

	unsigned int reg;

	u8 byte;



	/* gp registers start at index 1 */

	if (index == 0)

		return NULL;



	index--; /* make index 0-based */

	if (od < index * 32)

		return NULL;



	od -= index * 32;

	reg = od >> 5;



	if (reg >= count)

		return NULL;



	od &= (1 << 5) - 1;

	byte = 3 - (od >> 3);

	*bit = od & ((1 << 3) - 1);



	return &data[reg * 4 + byte];

}



int try_test_sas_gpio_gp_bit(unsigned int od, u8 *data, u8 index, u8 count)

{

	u8 *byte;

	u8 bit;



	byte = to_sas_gpio_gp_bit(od, data, index, count, &bit);

	if (!byte)

		return -1;



	return (*byte >> bit) & 1;

}

EXPORT_SYMBOL(try_test_sas_gpio_gp_bit);



static int sas_host_smp_write_gpio(struct sas_ha_struct *sas_ha, u8 *resp_data,

				   u8 reg_type, u8 reg_index, u8 reg_count,

				   u8 *req_data)

{

	struct sas_internal *i = to_sas_internal(sas_ha->core.shost->transportt);

	int written;



	if (i->dft->lldd_write_gpio == NULL) {

		resp_data[2] = SMP_RESP_FUNC_UNK;

		return 0;

	}



	written = i->dft->lldd_write_gpio(sas_ha, reg_type, reg_index,

					  reg_count, req_data);



	if (written < 0) {

		resp_data[2] = SMP_RESP_FUNC_FAILED;

		written = 0;

	} else

		resp_data[2] = SMP_RESP_FUNC_ACC;



	return written;

}



static void sas_report_phy_sata(struct sas_ha_struct *sas_ha, u8 *resp_data,

				u8 phy_id)

{
@@ -230,9 +315,23 @@ int sas_smp_host_handler(struct Scsi_Host *shost, struct request *req, 
		/* Can't implement; hosts have no routes */

		break;



	case SMP_WRITE_GPIO_REG:

		/* FIXME: need GPIO support in the transport class */

	case SMP_WRITE_GPIO_REG: {

		/* SFF-8485 v0.7 */

		const int base_frame_size = 11;

		int to_write = req_data[4];



		if (blk_rq_bytes(req) < base_frame_size + to_write * 4 ||

		    req->resid_len < base_frame_size + to_write * 4) {

			resp_data[2] = SMP_RESP_INV_FRM_LEN;

			break;

		}



		to_write = sas_host_smp_write_gpio(sas_ha, resp_data, req_data[2],

						   req_data[3], to_write, &req_data[8]);

		req->resid_len -= base_frame_size + to_write * 4;

		rsp->resid_len -= 8;

		break;

	}



	case SMP_CONF_ROUTE_INFO:

		/* Can't implement; hosts have no routes */

include/scsi/libsas.h

+11 −0
Original line number Diff line number Diff line
@@ -405,6 +405,13 @@ static inline void sas_phy_disconnected(struct asd_sas_phy *phy) 
	phy->linkrate = SAS_LINK_RATE_UNKNOWN;

}



static inline unsigned int to_sas_gpio_od(int device, int bit)

{

	return 3 * device + bit;

}



int try_test_sas_gpio_gp_bit(unsigned int od, u8 *data, u8 index, u8 count);



/* ---------- Tasks ---------- */

/*

      service_response |  SAS_TASK_COMPLETE  |  SAS_TASK_UNDELIVERED |
@@ -592,6 +599,10 @@ struct sas_domain_function_template { 


	/* Phy management */

	int (*lldd_control_phy)(struct asd_sas_phy *, enum phy_func, void *);



	/* GPIO support */

	int (*lldd_write_gpio)(struct sas_ha_struct *, u8 reg_type,

			       u8 reg_index, u8 reg_count, u8 *write_data);

};



extern int sas_register_ha(struct sas_ha_struct *);

include/scsi/sas.h

+8 −0
Original line number Diff line number Diff line
@@ -195,6 +195,14 @@ enum sas_open_rej_reason { 
	SAS_OREJ_RSVD_RETRY = 18,

};



enum sas_gpio_reg_type {

	SAS_GPIO_REG_CFG   = 0,

	SAS_GPIO_REG_RX    = 1,

	SAS_GPIO_REG_RX_GP = 2,

	SAS_GPIO_REG_TX    = 3,

	SAS_GPIO_REG_TX_GP = 4,

};



struct  dev_to_host_fis {

	u8     fis_type;	  /* 0x34 */

	u8     flags;

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