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linux/drivers/block/xsysace.c

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// SPDX-License-Identifier: GPL-2.0-only
/*
* Xilinx SystemACE device driver
*
* Copyright 2007 Secret Lab Technologies Ltd.
*/
/*
* The SystemACE chip is designed to configure FPGAs by loading an FPGA
* bitstream from a file on a CF card and squirting it into FPGAs connected
* to the SystemACE JTAG chain. It also has the advantage of providing an
* MPU interface which can be used to control the FPGA configuration process
* and to use the attached CF card for general purpose storage.
*
* This driver is a block device driver for the SystemACE.
*
* Initialization:
* The driver registers itself as a platform_device driver at module
* load time. The platform bus will take care of calling the
* ace_probe() method for all SystemACE instances in the system. Any
* number of SystemACE instances are supported. ace_probe() calls
* ace_setup() which initialized all data structures, reads the CF
* id structure and registers the device.
*
* Processing:
* Just about all of the heavy lifting in this driver is performed by
* a Finite State Machine (FSM). The driver needs to wait on a number
* of events; some raised by interrupts, some which need to be polled
* for. Describing all of the behaviour in a FSM seems to be the
* easiest way to keep the complexity low and make it easy to
* understand what the driver is doing. If the block ops or the
* request function need to interact with the hardware, then they
* simply need to flag the request and kick of FSM processing.
*
* The FSM itself is atomic-safe code which can be run from any
* context. The general process flow is:
* 1. obtain the ace->lock spinlock.
* 2. loop on ace_fsm_dostate() until the ace->fsm_continue flag is
* cleared.
* 3. release the lock.
*
* Individual states do not sleep in any way. If a condition needs to
* be waited for then the state much clear the fsm_continue flag and
* either schedule the FSM to be run again at a later time, or expect
* an interrupt to call the FSM when the desired condition is met.
*
* In normal operation, the FSM is processed at interrupt context
* either when the driver's tasklet is scheduled, or when an irq is
* raised by the hardware. The tasklet can be scheduled at any time.
* The request method in particular schedules the tasklet when a new
* request has been indicated by the block layer. Once started, the
* FSM proceeds as far as it can processing the request until it
* needs on a hardware event. At this point, it must yield execution.
*
* A state has two options when yielding execution:
* 1. ace_fsm_yield()
* - Call if need to poll for event.
* - clears the fsm_continue flag to exit the processing loop
* - reschedules the tasklet to run again as soon as possible
* 2. ace_fsm_yieldirq()
* - Call if an irq is expected from the HW
* - clears the fsm_continue flag to exit the processing loop
* - does not reschedule the tasklet so the FSM will not be processed
* again until an irq is received.
* After calling a yield function, the state must return control back
* to the FSM main loop.
*
* Additionally, the driver maintains a kernel timer which can process
* the FSM. If the FSM gets stalled, typically due to a missed
* interrupt, then the kernel timer will expire and the driver can
* continue where it left off.
*
* To Do:
* - Add FPGA configuration control interface.
* - Request major number from lanana
*/
#undef DEBUG
#include <linux/module.h>
#include <linux/ctype.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/blk-mq.h>
#include <linux/mutex.h>
#include <linux/ata.h>
#include <linux/hdreg.h>
#include <linux/platform_device.h>
#if defined(CONFIG_OF)
#include <linux/of_address.h>
#include <linux/of_device.h>
#include <linux/of_platform.h>
#endif
MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>");
MODULE_DESCRIPTION("Xilinx SystemACE device driver");
MODULE_LICENSE("GPL");
/* SystemACE register definitions */
#define ACE_BUSMODE (0x00)
#define ACE_STATUS (0x04)
#define ACE_STATUS_CFGLOCK (0x00000001)
#define ACE_STATUS_MPULOCK (0x00000002)
#define ACE_STATUS_CFGERROR (0x00000004) /* config controller error */
#define ACE_STATUS_CFCERROR (0x00000008) /* CF controller error */
#define ACE_STATUS_CFDETECT (0x00000010)
#define ACE_STATUS_DATABUFRDY (0x00000020)
#define ACE_STATUS_DATABUFMODE (0x00000040)
#define ACE_STATUS_CFGDONE (0x00000080)
#define ACE_STATUS_RDYFORCFCMD (0x00000100)
#define ACE_STATUS_CFGMODEPIN (0x00000200)
#define ACE_STATUS_CFGADDR_MASK (0x0000e000)
#define ACE_STATUS_CFBSY (0x00020000)
#define ACE_STATUS_CFRDY (0x00040000)
#define ACE_STATUS_CFDWF (0x00080000)
#define ACE_STATUS_CFDSC (0x00100000)
#define ACE_STATUS_CFDRQ (0x00200000)
#define ACE_STATUS_CFCORR (0x00400000)
#define ACE_STATUS_CFERR (0x00800000)
#define ACE_ERROR (0x08)
#define ACE_CFGLBA (0x0c)
#define ACE_MPULBA (0x10)
#define ACE_SECCNTCMD (0x14)
#define ACE_SECCNTCMD_RESET (0x0100)
#define ACE_SECCNTCMD_IDENTIFY (0x0200)
#define ACE_SECCNTCMD_READ_DATA (0x0300)
#define ACE_SECCNTCMD_WRITE_DATA (0x0400)
#define ACE_SECCNTCMD_ABORT (0x0600)
#define ACE_VERSION (0x16)
#define ACE_VERSION_REVISION_MASK (0x00FF)
#define ACE_VERSION_MINOR_MASK (0x0F00)
#define ACE_VERSION_MAJOR_MASK (0xF000)
#define ACE_CTRL (0x18)
#define ACE_CTRL_FORCELOCKREQ (0x0001)
#define ACE_CTRL_LOCKREQ (0x0002)
#define ACE_CTRL_FORCECFGADDR (0x0004)
#define ACE_CTRL_FORCECFGMODE (0x0008)
#define ACE_CTRL_CFGMODE (0x0010)
#define ACE_CTRL_CFGSTART (0x0020)
#define ACE_CTRL_CFGSEL (0x0040)
#define ACE_CTRL_CFGRESET (0x0080)
#define ACE_CTRL_DATABUFRDYIRQ (0x0100)
#define ACE_CTRL_ERRORIRQ (0x0200)
#define ACE_CTRL_CFGDONEIRQ (0x0400)
#define ACE_CTRL_RESETIRQ (0x0800)
#define ACE_CTRL_CFGPROG (0x1000)
#define ACE_CTRL_CFGADDR_MASK (0xe000)
#define ACE_FATSTAT (0x1c)
#define ACE_NUM_MINORS 16
#define ACE_SECTOR_SIZE (512)
#define ACE_FIFO_SIZE (32)
#define ACE_BUF_PER_SECTOR (ACE_SECTOR_SIZE / ACE_FIFO_SIZE)
#define ACE_BUS_WIDTH_8 0
#define ACE_BUS_WIDTH_16 1
struct ace_reg_ops;
struct ace_device {
/* driver state data */
int id;
int media_change;
int users;
struct list_head list;
/* finite state machine data */
struct tasklet_struct fsm_tasklet;
uint fsm_task; /* Current activity (ACE_TASK_*) */
uint fsm_state; /* Current state (ACE_FSM_STATE_*) */
uint fsm_continue_flag; /* cleared to exit FSM mainloop */
uint fsm_iter_num;
struct timer_list stall_timer;
/* Transfer state/result, use for both id and block request */
struct request *req; /* request being processed */
void *data_ptr; /* pointer to I/O buffer */
int data_count; /* number of buffers remaining */
int data_result; /* Result of transfer; 0 := success */
int id_req_count; /* count of id requests */
int id_result;
struct completion id_completion; /* used when id req finishes */
int in_irq;
/* Details of hardware device */
resource_size_t physaddr;
void __iomem *baseaddr;
int irq;
int bus_width; /* 0 := 8 bit; 1 := 16 bit */
struct ace_reg_ops *reg_ops;
int lock_count;
/* Block device data structures */
spinlock_t lock;
struct device *dev;
struct request_queue *queue;
struct gendisk *gd;
struct blk_mq_tag_set tag_set;
struct list_head rq_list;
/* Inserted CF card parameters */
u16 cf_id[ATA_ID_WORDS];
};
static DEFINE_MUTEX(xsysace_mutex);
static int ace_major;
/* ---------------------------------------------------------------------
* Low level register access
*/
struct ace_reg_ops {
u16(*in) (struct ace_device * ace, int reg);
void (*out) (struct ace_device * ace, int reg, u16 val);
void (*datain) (struct ace_device * ace);
void (*dataout) (struct ace_device * ace);
};
/* 8 Bit bus width */
static u16 ace_in_8(struct ace_device *ace, int reg)
{
void __iomem *r = ace->baseaddr + reg;
return in_8(r) | (in_8(r + 1) << 8);
}
static void ace_out_8(struct ace_device *ace, int reg, u16 val)
{
void __iomem *r = ace->baseaddr + reg;
out_8(r, val);
out_8(r + 1, val >> 8);
}
static void ace_datain_8(struct ace_device *ace)
{
void __iomem *r = ace->baseaddr + 0x40;
u8 *dst = ace->data_ptr;
int i = ACE_FIFO_SIZE;
while (i--)
*dst++ = in_8(r++);
ace->data_ptr = dst;
}
static void ace_dataout_8(struct ace_device *ace)
{
void __iomem *r = ace->baseaddr + 0x40;
u8 *src = ace->data_ptr;
int i = ACE_FIFO_SIZE;
while (i--)
out_8(r++, *src++);
ace->data_ptr = src;
}
static struct ace_reg_ops ace_reg_8_ops = {
.in = ace_in_8,
.out = ace_out_8,
.datain = ace_datain_8,
.dataout = ace_dataout_8,
};
/* 16 bit big endian bus attachment */
static u16 ace_in_be16(struct ace_device *ace, int reg)
{
return in_be16(ace->baseaddr + reg);
}
static void ace_out_be16(struct ace_device *ace, int reg, u16 val)
{
out_be16(ace->baseaddr + reg, val);
}
static void ace_datain_be16(struct ace_device *ace)
{
int i = ACE_FIFO_SIZE / 2;
u16 *dst = ace->data_ptr;
while (i--)
*dst++ = in_le16(ace->baseaddr + 0x40);
ace->data_ptr = dst;
}
static void ace_dataout_be16(struct ace_device *ace)
{
int i = ACE_FIFO_SIZE / 2;
u16 *src = ace->data_ptr;
while (i--)
out_le16(ace->baseaddr + 0x40, *src++);
ace->data_ptr = src;
}
/* 16 bit little endian bus attachment */
static u16 ace_in_le16(struct ace_device *ace, int reg)
{
return in_le16(ace->baseaddr + reg);
}
static void ace_out_le16(struct ace_device *ace, int reg, u16 val)
{
out_le16(ace->baseaddr + reg, val);
}
static void ace_datain_le16(struct ace_device *ace)
{
int i = ACE_FIFO_SIZE / 2;
u16 *dst = ace->data_ptr;
while (i--)
*dst++ = in_be16(ace->baseaddr + 0x40);
ace->data_ptr = dst;
}
static void ace_dataout_le16(struct ace_device *ace)
{
int i = ACE_FIFO_SIZE / 2;
u16 *src = ace->data_ptr;
while (i--)
out_be16(ace->baseaddr + 0x40, *src++);
ace->data_ptr = src;
}
static struct ace_reg_ops ace_reg_be16_ops = {
.in = ace_in_be16,
.out = ace_out_be16,
.datain = ace_datain_be16,
.dataout = ace_dataout_be16,
};
static struct ace_reg_ops ace_reg_le16_ops = {
.in = ace_in_le16,
.out = ace_out_le16,
.datain = ace_datain_le16,
.dataout = ace_dataout_le16,
};
static inline u16 ace_in(struct ace_device *ace, int reg)
{
return ace->reg_ops->in(ace, reg);
}
static inline u32 ace_in32(struct ace_device *ace, int reg)
{
return ace_in(ace, reg) | (ace_in(ace, reg + 2) << 16);
}
static inline void ace_out(struct ace_device *ace, int reg, u16 val)
{
ace->reg_ops->out(ace, reg, val);
}
static inline void ace_out32(struct ace_device *ace, int reg, u32 val)
{
ace_out(ace, reg, val);
ace_out(ace, reg + 2, val >> 16);
}
/* ---------------------------------------------------------------------
* Debug support functions
*/
#if defined(DEBUG)
static void ace_dump_mem(void *base, int len)
{
const char *ptr = base;
int i, j;
for (i = 0; i < len; i += 16) {
printk(KERN_INFO "%.8x:", i);
for (j = 0; j < 16; j++) {
if (!(j % 4))
printk(" ");
printk("%.2x", ptr[i + j]);
}
printk(" ");
for (j = 0; j < 16; j++)
printk("%c", isprint(ptr[i + j]) ? ptr[i + j] : '.');
printk("\n");
}
}
#else
static inline void ace_dump_mem(void *base, int len)
{
}
#endif
static void ace_dump_regs(struct ace_device *ace)
{
dev_info(ace->dev,
" ctrl: %.8x seccnt/cmd: %.4x ver:%.4x\n"
" status:%.8x mpu_lba:%.8x busmode:%4x\n"
" error: %.8x cfg_lba:%.8x fatstat:%.4x\n",
ace_in32(ace, ACE_CTRL),
ace_in(ace, ACE_SECCNTCMD),
ace_in(ace, ACE_VERSION),
ace_in32(ace, ACE_STATUS),
ace_in32(ace, ACE_MPULBA),
ace_in(ace, ACE_BUSMODE),
ace_in32(ace, ACE_ERROR),
ace_in32(ace, ACE_CFGLBA), ace_in(ace, ACE_FATSTAT));
}
static void ace_fix_driveid(u16 *id)
{
#if defined(__BIG_ENDIAN)
int i;
/* All half words have wrong byte order; swap the bytes */
for (i = 0; i < ATA_ID_WORDS; i++, id++)
*id = le16_to_cpu(*id);
#endif
}
/* ---------------------------------------------------------------------
* Finite State Machine (FSM) implementation
*/
/* FSM tasks; used to direct state transitions */
#define ACE_TASK_IDLE 0
#define ACE_TASK_IDENTIFY 1
#define ACE_TASK_READ 2
#define ACE_TASK_WRITE 3
#define ACE_FSM_NUM_TASKS 4
/* FSM state definitions */
#define ACE_FSM_STATE_IDLE 0
#define ACE_FSM_STATE_REQ_LOCK 1
#define ACE_FSM_STATE_WAIT_LOCK 2
#define ACE_FSM_STATE_WAIT_CFREADY 3
#define ACE_FSM_STATE_IDENTIFY_PREPARE 4
#define ACE_FSM_STATE_IDENTIFY_TRANSFER 5
#define ACE_FSM_STATE_IDENTIFY_COMPLETE 6
#define ACE_FSM_STATE_REQ_PREPARE 7
#define ACE_FSM_STATE_REQ_TRANSFER 8
#define ACE_FSM_STATE_REQ_COMPLETE 9
#define ACE_FSM_STATE_ERROR 10
#define ACE_FSM_NUM_STATES 11
/* Set flag to exit FSM loop and reschedule tasklet */
static inline void ace_fsm_yieldpoll(struct ace_device *ace)
{
tasklet_schedule(&ace->fsm_tasklet);
ace->fsm_continue_flag = 0;
}
static inline void ace_fsm_yield(struct ace_device *ace)
{
dev_dbg(ace->dev, "%s()\n", __func__);
ace_fsm_yieldpoll(ace);
}
/* Set flag to exit FSM loop and wait for IRQ to reschedule tasklet */
static inline void ace_fsm_yieldirq(struct ace_device *ace)
{
dev_dbg(ace->dev, "ace_fsm_yieldirq()\n");
if (ace->irq > 0)
ace->fsm_continue_flag = 0;
else
ace_fsm_yieldpoll(ace);
}
static bool ace_has_next_request(struct request_queue *q)
{
struct ace_device *ace = q->queuedata;
return !list_empty(&ace->rq_list);
}
/* Get the next read/write request; ending requests that we don't handle */
static struct request *ace_get_next_request(struct request_queue *q)
{
struct ace_device *ace = q->queuedata;
struct request *rq;
rq = list_first_entry_or_null(&ace->rq_list, struct request, queuelist);
if (rq) {
list_del_init(&rq->queuelist);
blk_mq_start_request(rq);
}
return NULL;
}
static void ace_fsm_dostate(struct ace_device *ace)
{
struct request *req;
u32 status;
u16 val;
int count;
#if defined(DEBUG)
dev_dbg(ace->dev, "fsm_state=%i, id_req_count=%i\n",
ace->fsm_state, ace->id_req_count);
#endif
/* Verify that there is actually a CF in the slot. If not, then
* bail out back to the idle state and wake up all the waiters */
status = ace_in32(ace, ACE_STATUS);
if ((status & ACE_STATUS_CFDETECT) == 0) {
ace->fsm_state = ACE_FSM_STATE_IDLE;
ace->media_change = 1;
set_capacity(ace->gd, 0);
dev_info(ace->dev, "No CF in slot\n");
/* Drop all in-flight and pending requests */
if (ace->req) {
blk_mq_end_request(ace->req, BLK_STS_IOERR);
ace->req = NULL;
}
while ((req = ace_get_next_request(ace->queue)) != NULL)
blk_mq_end_request(req, BLK_STS_IOERR);
/* Drop back to IDLE state and notify waiters */
ace->fsm_state = ACE_FSM_STATE_IDLE;
ace->id_result = -EIO;
while (ace->id_req_count) {
complete(&ace->id_completion);
ace->id_req_count--;
}
}
switch (ace->fsm_state) {
case ACE_FSM_STATE_IDLE:
/* See if there is anything to do */
if (ace->id_req_count || ace_has_next_request(ace->queue)) {
ace->fsm_iter_num++;
ace->fsm_state = ACE_FSM_STATE_REQ_LOCK;
mod_timer(&ace->stall_timer, jiffies + HZ);
if (!timer_pending(&ace->stall_timer))
add_timer(&ace->stall_timer);
break;
}
del_timer(&ace->stall_timer);
ace->fsm_continue_flag = 0;
break;
case ACE_FSM_STATE_REQ_LOCK:
if (ace_in(ace, ACE_STATUS) & ACE_STATUS_MPULOCK) {
/* Already have the lock, jump to next state */
ace->fsm_state = ACE_FSM_STATE_WAIT_CFREADY;
break;
}
/* Request the lock */
val = ace_in(ace, ACE_CTRL);
ace_out(ace, ACE_CTRL, val | ACE_CTRL_LOCKREQ);
ace->fsm_state = ACE_FSM_STATE_WAIT_LOCK;
break;
case ACE_FSM_STATE_WAIT_LOCK:
if (ace_in(ace, ACE_STATUS) & ACE_STATUS_MPULOCK) {
/* got the lock; move to next state */
ace->fsm_state = ACE_FSM_STATE_WAIT_CFREADY;
break;
}
/* wait a bit for the lock */
ace_fsm_yield(ace);
break;
case ACE_FSM_STATE_WAIT_CFREADY:
status = ace_in32(ace, ACE_STATUS);
if (!(status & ACE_STATUS_RDYFORCFCMD) ||
(status & ACE_STATUS_CFBSY)) {
/* CF card isn't ready; it needs to be polled */
ace_fsm_yield(ace);
break;
}
/* Device is ready for command; determine what to do next */
if (ace->id_req_count)
ace->fsm_state = ACE_FSM_STATE_IDENTIFY_PREPARE;
else
ace->fsm_state = ACE_FSM_STATE_REQ_PREPARE;
break;
case ACE_FSM_STATE_IDENTIFY_PREPARE:
/* Send identify command */
ace->fsm_task = ACE_TASK_IDENTIFY;
ace->data_ptr = ace->cf_id;
ace->data_count = ACE_BUF_PER_SECTOR;
ace_out(ace, ACE_SECCNTCMD, ACE_SECCNTCMD_IDENTIFY);
/* As per datasheet, put config controller in reset */
val = ace_in(ace, ACE_CTRL);
ace_out(ace, ACE_CTRL, val | ACE_CTRL_CFGRESET);
/* irq handler takes over from this point; wait for the
* transfer to complete */
ace->fsm_state = ACE_FSM_STATE_IDENTIFY_TRANSFER;
ace_fsm_yieldirq(ace);
break;
case ACE_FSM_STATE_IDENTIFY_TRANSFER:
/* Check that the sysace is ready to receive data */
status = ace_in32(ace, ACE_STATUS);
if (status & ACE_STATUS_CFBSY) {
dev_dbg(ace->dev, "CFBSY set; t=%i iter=%i dc=%i\n",
ace->fsm_task, ace->fsm_iter_num,
ace->data_count);
ace_fsm_yield(ace);
break;
}
if (!(status & ACE_STATUS_DATABUFRDY)) {
ace_fsm_yield(ace);
break;
}
/* Transfer the next buffer */
ace->reg_ops->datain(ace);
ace->data_count--;
/* If there are still buffers to be transfers; jump out here */
if (ace->data_count != 0) {
ace_fsm_yieldirq(ace);
break;
}
/* transfer finished; kick state machine */
dev_dbg(ace->dev, "identify finished\n");
ace->fsm_state = ACE_FSM_STATE_IDENTIFY_COMPLETE;
break;
case ACE_FSM_STATE_IDENTIFY_COMPLETE:
ace_fix_driveid(ace->cf_id);
ace_dump_mem(ace->cf_id, 512); /* Debug: Dump out disk ID */
if (ace->data_result) {
/* Error occurred, disable the disk */
ace->media_change = 1;
set_capacity(ace->gd, 0);
dev_err(ace->dev, "error fetching CF id (%i)\n",
ace->data_result);
} else {
ace->media_change = 0;
/* Record disk parameters */
set_capacity(ace->gd,
ata_id_u32(ace->cf_id, ATA_ID_LBA_CAPACITY));
dev_info(ace->dev, "capacity: %i sectors\n",
ata_id_u32(ace->cf_id, ATA_ID_LBA_CAPACITY));
}
/* We're done, drop to IDLE state and notify waiters */
ace->fsm_state = ACE_FSM_STATE_IDLE;
ace->id_result = ace->data_result;
while (ace->id_req_count) {
complete(&ace->id_completion);
ace->id_req_count--;
}
break;
case ACE_FSM_STATE_REQ_PREPARE:
req = ace_get_next_request(ace->queue);
if (!req) {
ace->fsm_state = ACE_FSM_STATE_IDLE;
break;
}
/* Okay, it's a data request, set it up for transfer */
dev_dbg(ace->dev,
"request: sec=%llx hcnt=%x, ccnt=%x, dir=%i\n",
(unsigned long long)blk_rq_pos(req),
blk_rq_sectors(req), blk_rq_cur_sectors(req),
rq_data_dir(req));
ace->req = req;
ace->data_ptr = bio_data(req->bio);
ace->data_count = blk_rq_cur_sectors(req) * ACE_BUF_PER_SECTOR;
ace_out32(ace, ACE_MPULBA, blk_rq_pos(req) & 0x0FFFFFFF);
count = blk_rq_sectors(req);
if (rq_data_dir(req)) {
/* Kick off write request */
dev_dbg(ace->dev, "write data\n");
ace->fsm_task = ACE_TASK_WRITE;
ace_out(ace, ACE_SECCNTCMD,
count | ACE_SECCNTCMD_WRITE_DATA);
} else {
/* Kick off read request */
dev_dbg(ace->dev, "read data\n");
ace->fsm_task = ACE_TASK_READ;
ace_out(ace, ACE_SECCNTCMD,
count | ACE_SECCNTCMD_READ_DATA);
}
/* As per datasheet, put config controller in reset */
val = ace_in(ace, ACE_CTRL);
ace_out(ace, ACE_CTRL, val | ACE_CTRL_CFGRESET);
/* Move to the transfer state. The systemace will raise
* an interrupt once there is something to do
*/
ace->fsm_state = ACE_FSM_STATE_REQ_TRANSFER;
if (ace->fsm_task == ACE_TASK_READ)
ace_fsm_yieldirq(ace); /* wait for data ready */
break;
case ACE_FSM_STATE_REQ_TRANSFER:
/* Check that the sysace is ready to receive data */
status = ace_in32(ace, ACE_STATUS);
if (status & ACE_STATUS_CFBSY) {
dev_dbg(ace->dev,
"CFBSY set; t=%i iter=%i c=%i dc=%i irq=%i\n",
ace->fsm_task, ace->fsm_iter_num,
blk_rq_cur_sectors(ace->req) * 16,
ace->data_count, ace->in_irq);
ace_fsm_yield(ace); /* need to poll CFBSY bit */
break;
}
if (!(status & ACE_STATUS_DATABUFRDY)) {
dev_dbg(ace->dev,
"DATABUF not set; t=%i iter=%i c=%i dc=%i irq=%i\n",
ace->fsm_task, ace->fsm_iter_num,
blk_rq_cur_sectors(ace->req) * 16,
ace->data_count, ace->in_irq);
ace_fsm_yieldirq(ace);
break;
}
/* Transfer the next buffer */
if (ace->fsm_task == ACE_TASK_WRITE)
ace->reg_ops->dataout(ace);
else
ace->reg_ops->datain(ace);
ace->data_count--;
/* If there are still buffers to be transfers; jump out here */
if (ace->data_count != 0) {
ace_fsm_yieldirq(ace);
break;
}
/* bio finished; is there another one? */
if (blk_update_request(ace->req, BLK_STS_OK,
blk_rq_cur_bytes(ace->req))) {
/* dev_dbg(ace->dev, "next block; h=%u c=%u\n",
* blk_rq_sectors(ace->req),
* blk_rq_cur_sectors(ace->req));
*/
ace->data_ptr = bio_data(ace->req->bio);
ace->data_count = blk_rq_cur_sectors(ace->req) * 16;
ace_fsm_yieldirq(ace);
break;
}
ace->fsm_state = ACE_FSM_STATE_REQ_COMPLETE;
break;
case ACE_FSM_STATE_REQ_COMPLETE:
ace->req = NULL;
/* Finished request; go to idle state */
ace->fsm_state = ACE_FSM_STATE_IDLE;
break;
default:
ace->fsm_state = ACE_FSM_STATE_IDLE;
break;
}
}
static void ace_fsm_tasklet(unsigned long data)
{
struct ace_device *ace = (void *)data;
unsigned long flags;
spin_lock_irqsave(&ace->lock, flags);
/* Loop over state machine until told to stop */
ace->fsm_continue_flag = 1;
while (ace->fsm_continue_flag)
ace_fsm_dostate(ace);
spin_unlock_irqrestore(&ace->lock, flags);
}
static void ace_stall_timer(struct timer_list *t)
{
struct ace_device *ace = from_timer(ace, t, stall_timer);
unsigned long flags;
dev_warn(ace->dev,
"kicking stalled fsm; state=%i task=%i iter=%i dc=%i\n",
ace->fsm_state, ace->fsm_task, ace->fsm_iter_num,
ace->data_count);
spin_lock_irqsave(&ace->lock, flags);
/* Rearm the stall timer *before* entering FSM (which may then
* delete the timer) */
mod_timer(&ace->stall_timer, jiffies + HZ);
/* Loop over state machine until told to stop */
ace->fsm_continue_flag = 1;
while (ace->fsm_continue_flag)
ace_fsm_dostate(ace);
spin_unlock_irqrestore(&ace->lock, flags);
}
/* ---------------------------------------------------------------------
* Interrupt handling routines
*/
static int ace_interrupt_checkstate(struct ace_device *ace)
{
u32 sreg = ace_in32(ace, ACE_STATUS);
u16 creg = ace_in(ace, ACE_CTRL);
/* Check for error occurrence */
if ((sreg & (ACE_STATUS_CFGERROR | ACE_STATUS_CFCERROR)) &&
(creg & ACE_CTRL_ERRORIRQ)) {
dev_err(ace->dev, "transfer failure\n");
ace_dump_regs(ace);
return -EIO;
}
return 0;
}
static irqreturn_t ace_interrupt(int irq, void *dev_id)
{
u16 creg;
struct ace_device *ace = dev_id;
/* be safe and get the lock */
spin_lock(&ace->lock);
ace->in_irq = 1;
/* clear the interrupt */
creg = ace_in(ace, ACE_CTRL);
ace_out(ace, ACE_CTRL, creg | ACE_CTRL_RESETIRQ);
ace_out(ace, ACE_CTRL, creg);
/* check for IO failures */
if (ace_interrupt_checkstate(ace))
ace->data_result = -EIO;
if (ace->fsm_task == 0) {
dev_err(ace->dev,
"spurious irq; stat=%.8x ctrl=%.8x cmd=%.4x\n",
ace_in32(ace, ACE_STATUS), ace_in32(ace, ACE_CTRL),
ace_in(ace, ACE_SECCNTCMD));
dev_err(ace->dev, "fsm_task=%i fsm_state=%i data_count=%i\n",
ace->fsm_task, ace->fsm_state, ace->data_count);
}
/* Loop over state machine until told to stop */
ace->fsm_continue_flag = 1;
while (ace->fsm_continue_flag)
ace_fsm_dostate(ace);
/* done with interrupt; drop the lock */
ace->in_irq = 0;
spin_unlock(&ace->lock);
return IRQ_HANDLED;
}
/* ---------------------------------------------------------------------
* Block ops
*/
static blk_status_t ace_queue_rq(struct blk_mq_hw_ctx *hctx,
const struct blk_mq_queue_data *bd)
{
struct ace_device *ace = hctx->queue->queuedata;
struct request *req = bd->rq;
if (blk_rq_is_passthrough(req)) {
blk_mq_start_request(req);
return BLK_STS_IOERR;
}
spin_lock_irq(&ace->lock);
list_add_tail(&req->queuelist, &ace->rq_list);
spin_unlock_irq(&ace->lock);
tasklet_schedule(&ace->fsm_tasklet);
return BLK_STS_OK;
}
static unsigned int ace_check_events(struct gendisk *gd, unsigned int clearing)
{
struct ace_device *ace = gd->private_data;
dev_dbg(ace->dev, "ace_check_events(): %i\n", ace->media_change);
return ace->media_change ? DISK_EVENT_MEDIA_CHANGE : 0;
}
static void ace_media_changed(struct ace_device *ace)
{
unsigned long flags;
dev_dbg(ace->dev, "requesting cf id and scheduling tasklet\n");
spin_lock_irqsave(&ace->lock, flags);
ace->id_req_count++;
spin_unlock_irqrestore(&ace->lock, flags);
tasklet_schedule(&ace->fsm_tasklet);
wait_for_completion(&ace->id_completion);
dev_dbg(ace->dev, "revalidate complete\n");
}
static int ace_open(struct block_device *bdev, fmode_t mode)
{
struct ace_device *ace = bdev->bd_disk->private_data;
unsigned long flags;
dev_dbg(ace->dev, "ace_open() users=%i\n", ace->users + 1);
mutex_lock(&xsysace_mutex);
spin_lock_irqsave(&ace->lock, flags);
ace->users++;
spin_unlock_irqrestore(&ace->lock, flags);
if (bdev_check_media_change(bdev) && ace->media_change)
ace_media_changed(ace);
mutex_unlock(&xsysace_mutex);
return 0;
}
static void ace_release(struct gendisk *disk, fmode_t mode)
{
struct ace_device *ace = disk->private_data;
unsigned long flags;
u16 val;
dev_dbg(ace->dev, "ace_release() users=%i\n", ace->users - 1);
mutex_lock(&xsysace_mutex);
spin_lock_irqsave(&ace->lock, flags);
ace->users--;
if (ace->users == 0) {
val = ace_in(ace, ACE_CTRL);
ace_out(ace, ACE_CTRL, val & ~ACE_CTRL_LOCKREQ);
}
spin_unlock_irqrestore(&ace->lock, flags);
mutex_unlock(&xsysace_mutex);
}
static int ace_getgeo(struct block_device *bdev, struct hd_geometry *geo)
{
struct ace_device *ace = bdev->bd_disk->private_data;
u16 *cf_id = ace->cf_id;
dev_dbg(ace->dev, "ace_getgeo()\n");
geo->heads = cf_id[ATA_ID_HEADS];
geo->sectors = cf_id[ATA_ID_SECTORS];
geo->cylinders = cf_id[ATA_ID_CYLS];
return 0;
}
static const struct block_device_operations ace_fops = {
.owner = THIS_MODULE,
.open = ace_open,
.release = ace_release,
.check_events = ace_check_events,
.getgeo = ace_getgeo,
};
static const struct blk_mq_ops ace_mq_ops = {
.queue_rq = ace_queue_rq,
};
/* --------------------------------------------------------------------
* SystemACE device setup/teardown code
*/
static int ace_setup(struct ace_device *ace)
{
u16 version;
u16 val;
int rc;
dev_dbg(ace->dev, "ace_setup(ace=0x%p)\n", ace);
dev_dbg(ace->dev, "physaddr=0x%llx irq=%i\n",
(unsigned long long)ace->physaddr, ace->irq);
spin_lock_init(&ace->lock);
init_completion(&ace->id_completion);
INIT_LIST_HEAD(&ace->rq_list);
/*
* Map the device
*/
ace->baseaddr = ioremap(ace->physaddr, 0x80);
if (!ace->baseaddr)
goto err_ioremap;
/*
* Initialize the state machine tasklet and stall timer
*/
tasklet_init(&ace->fsm_tasklet, ace_fsm_tasklet, (unsigned long)ace);
timer_setup(&ace->stall_timer, ace_stall_timer, 0);
/*
* Initialize the request queue
*/
ace->queue = blk_mq_init_sq_queue(&ace->tag_set, &ace_mq_ops, 2,
BLK_MQ_F_SHOULD_MERGE);
if (IS_ERR(ace->queue)) {
rc = PTR_ERR(ace->queue);
ace->queue = NULL;
goto err_blk_initq;
}
ace->queue->queuedata = ace;
blk_queue_logical_block_size(ace->queue, 512);
blk_queue_bounce_limit(ace->queue, BLK_BOUNCE_HIGH);
/*
* Allocate and initialize GD structure
*/
ace->gd = alloc_disk(ACE_NUM_MINORS);
if (!ace->gd)
goto err_alloc_disk;
ace->gd->major = ace_major;
ace->gd->first_minor = ace->id * ACE_NUM_MINORS;
ace->gd->fops = &ace_fops;
ace->gd->events = DISK_EVENT_MEDIA_CHANGE;
ace->gd->queue = ace->queue;
ace->gd->private_data = ace;
snprintf(ace->gd->disk_name, 32, "xs%c", ace->id + 'a');
/* set bus width */
if (ace->bus_width == ACE_BUS_WIDTH_16) {
/* 0x0101 should work regardless of endianess */
ace_out_le16(ace, ACE_BUSMODE, 0x0101);
/* read it back to determine endianess */
if (ace_in_le16(ace, ACE_BUSMODE) == 0x0001)
ace->reg_ops = &ace_reg_le16_ops;
else
ace->reg_ops = &ace_reg_be16_ops;
} else {
ace_out_8(ace, ACE_BUSMODE, 0x00);
ace->reg_ops = &ace_reg_8_ops;
}
/* Make sure version register is sane */
version = ace_in(ace, ACE_VERSION);
if ((version == 0) || (version == 0xFFFF))
goto err_read;
/* Put sysace in a sane state by clearing most control reg bits */
ace_out(ace, ACE_CTRL, ACE_CTRL_FORCECFGMODE |
ACE_CTRL_DATABUFRDYIRQ | ACE_CTRL_ERRORIRQ);
/* Now we can hook up the irq handler */
if (ace->irq > 0) {
rc = request_irq(ace->irq, ace_interrupt, 0, "systemace", ace);
if (rc) {
/* Failure - fall back to polled mode */
dev_err(ace->dev, "request_irq failed\n");
ace->irq = rc;
}
}
/* Enable interrupts */
val = ace_in(ace, ACE_CTRL);
val |= ACE_CTRL_DATABUFRDYIRQ | ACE_CTRL_ERRORIRQ;
ace_out(ace, ACE_CTRL, val);
/* Print the identification */
dev_info(ace->dev, "Xilinx SystemACE revision %i.%i.%i\n",
(version >> 12) & 0xf, (version >> 8) & 0x0f, version & 0xff);
dev_dbg(ace->dev, "physaddr 0x%llx, mapped to 0x%p, irq=%i\n",
(unsigned long long) ace->physaddr, ace->baseaddr, ace->irq);
ace->media_change = 1;
ace_media_changed(ace);
/* Make the sysace device 'live' */
add_disk(ace->gd);
return 0;
err_read:
/* prevent double queue cleanup */
ace->gd->queue = NULL;
put_disk(ace->gd);
err_alloc_disk:
blk_cleanup_queue(ace->queue);
blk_mq_free_tag_set(&ace->tag_set);
err_blk_initq:
iounmap(ace->baseaddr);
err_ioremap:
dev_info(ace->dev, "xsysace: error initializing device at 0x%llx\n",
(unsigned long long) ace->physaddr);
return -ENOMEM;
}
static void ace_teardown(struct ace_device *ace)
{
if (ace->gd) {
del_gendisk(ace->gd);
put_disk(ace->gd);
}
if (ace->queue) {
blk_cleanup_queue(ace->queue);
blk_mq_free_tag_set(&ace->tag_set);
}
tasklet_kill(&ace->fsm_tasklet);
if (ace->irq > 0)
free_irq(ace->irq, ace);
iounmap(ace->baseaddr);
}
static int ace_alloc(struct device *dev, int id, resource_size_t physaddr,
int irq, int bus_width)
{
struct ace_device *ace;
int rc;
dev_dbg(dev, "ace_alloc(%p)\n", dev);
/* Allocate and initialize the ace device structure */
ace = kzalloc(sizeof(struct ace_device), GFP_KERNEL);
if (!ace) {
rc = -ENOMEM;
goto err_alloc;
}
ace->dev = dev;
ace->id = id;
ace->physaddr = physaddr;
ace->irq = irq;
ace->bus_width = bus_width;
/* Call the setup code */
rc = ace_setup(ace);
if (rc)
goto err_setup;
dev_set_drvdata(dev, ace);
return 0;
err_setup:
dev_set_drvdata(dev, NULL);
kfree(ace);
err_alloc:
dev_err(dev, "could not initialize device, err=%i\n", rc);
return rc;
}
static void ace_free(struct device *dev)
{
struct ace_device *ace = dev_get_drvdata(dev);
dev_dbg(dev, "ace_free(%p)\n", dev);
if (ace) {
ace_teardown(ace);
dev_set_drvdata(dev, NULL);
kfree(ace);
}
}
/* ---------------------------------------------------------------------
* Platform Bus Support
*/
static int ace_probe(struct platform_device *dev)
{
int bus_width = ACE_BUS_WIDTH_16; /* FIXME: should not be hard coded */
resource_size_t physaddr;
struct resource *res;
u32 id = dev->id;
int irq;
int i;
dev_dbg(&dev->dev, "ace_probe(%p)\n", dev);
/* device id and bus width */
if (of_property_read_u32(dev->dev.of_node, "port-number", &id))
id = 0;
if (of_find_property(dev->dev.of_node, "8-bit", NULL))
bus_width = ACE_BUS_WIDTH_8;
res = platform_get_resource(dev, IORESOURCE_MEM, 0);
if (!res)
return -EINVAL;
physaddr = res->start;
if (!physaddr)
return -ENODEV;
irq = platform_get_irq_optional(dev, 0);
/* Call the bus-independent setup code */
return ace_alloc(&dev->dev, id, physaddr, irq, bus_width);
}
/*
* Platform bus remove() method
*/
static int ace_remove(struct platform_device *dev)
{
ace_free(&dev->dev);
return 0;
}
#if defined(CONFIG_OF)
/* Match table for of_platform binding */
static const struct of_device_id ace_of_match[] = {
{ .compatible = "xlnx,opb-sysace-1.00.b", },
{ .compatible = "xlnx,opb-sysace-1.00.c", },
{ .compatible = "xlnx,xps-sysace-1.00.a", },
{ .compatible = "xlnx,sysace", },
{},
};
MODULE_DEVICE_TABLE(of, ace_of_match);
#else /* CONFIG_OF */
#define ace_of_match NULL
#endif /* CONFIG_OF */
static struct platform_driver ace_platform_driver = {
.probe = ace_probe,
.remove = ace_remove,
.driver = {
.name = "xsysace",
.of_match_table = ace_of_match,
},
};
/* ---------------------------------------------------------------------
* Module init/exit routines
*/
static int __init ace_init(void)
{
int rc;
ace_major = register_blkdev(ace_major, "xsysace");
if (ace_major <= 0) {
rc = -ENOMEM;
goto err_blk;
}
rc = platform_driver_register(&ace_platform_driver);
if (rc)
goto err_plat;
pr_info("Xilinx SystemACE device driver, major=%i\n", ace_major);
return 0;
err_plat:
unregister_blkdev(ace_major, "xsysace");
err_blk:
printk(KERN_ERR "xsysace: registration failed; err=%i\n", rc);
return rc;
}
module_init(ace_init);
static void __exit ace_exit(void)
{
pr_debug("Unregistering Xilinx SystemACE driver\n");
platform_driver_unregister(&ace_platform_driver);
unregister_blkdev(ace_major, "xsysace");
}
module_exit(ace_exit);
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