[RFC] Xilinx SystemACE device driver
Grant Likely
grant.likely at secretlab.ca
Sun Apr 15 11:23:14 EST 2007
Add support for block device access to the Xilinx SystemACE Compact
flash interface
Signed-off-by: Grant Likely <grant.likely at secretlab.ca>
---
I think this driver is in pretty good shape. I've got a few things to
clean up a bit. Specifically, I'm still working on error handling and
making sure that the state machine is sane at all times.
I would appreciate any review/comments. One area where I am undecided is
the format of the state machine. The current code uses one big function
with a large switch() statment for each state. I'm considering breaking
this up into a seperate function for each state, and adding a static
state table with pointers to each state function.
I feel this driver is pretty close to done, and I'd like to get it into
mainline for the 2.6.22 timeframe.
Cheers,
g.
drivers/block/Kconfig | 6 +
drivers/block/Makefile | 1 +
drivers/block/xsysace.c | 1070 +++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 1077 insertions(+), 0 deletions(-)
create mode 100644 drivers/block/xsysace.c
diff --git a/drivers/block/Kconfig b/drivers/block/Kconfig
index 17ee97f..08ad23c 100644
--- a/drivers/block/Kconfig
+++ b/drivers/block/Kconfig
@@ -453,6 +453,12 @@ config ATA_OVER_ETH
This driver provides Support for ATA over Ethernet block
devices like the Coraid EtherDrive (R) Storage Blade.
+config XILINX_SYSACE
+ tristate "Xilinx SystemACE support"
+ depends on XILINX_VIRTEX
+ help
+ Include support for the Xilinx SystemACE CompactFlash interface
+
endmenu
endif
diff --git a/drivers/block/Makefile b/drivers/block/Makefile
index dd88e33..31ea323 100644
--- a/drivers/block/Makefile
+++ b/drivers/block/Makefile
@@ -28,4 +28,5 @@ obj-$(CONFIG_BLK_DEV_CRYPTOLOOP) += cryptoloop.o
obj-$(CONFIG_VIODASD) += viodasd.o
obj-$(CONFIG_BLK_DEV_SX8) += sx8.o
obj-$(CONFIG_BLK_DEV_UB) += ub.o
+obj-$(CONFIG_XILINX_SYSACE) += xsysace.o
diff --git a/drivers/block/xsysace.c b/drivers/block/xsysace.c
new file mode 100644
index 0000000..e8b4cd4
--- /dev/null
+++ b/drivers/block/xsysace.c
@@ -0,0 +1,1070 @@
+/*
+ * Xilinx SystemACE device driver
+ *
+ * Copyright 2007 Secret Lab Technologies Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation.
+ */
+
+/*
+ * 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
+ * - Add legacy device geometry ioctl
+ */
+
+#undef DEBUG
+#undef DEBUG_ENDIAN /* Uncomment to debug register endinaness */
+
+#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/blkdev.h>
+#include <linux/hdreg.h>
+#include <linux/platform_device.h>
+
+MODULE_AUTHOR("Grant Likely <grant.likely at 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_BUF_PER_SECTOR (512 / 32) /* 512_byte_sector / 32_byte_fifo */
+
+/* ---------------------------------------------------------------------
+ * Low level register access
+ */
+
+/* register access macros */
+#if 1 /* Little endian 16-bit regs */
+#define ace_reg_read8(ace, reg) in_8(ace->baseaddr + reg)
+#define ace_reg_read16(ace, reg) in_le16(ace->baseaddr + reg)
+#define ace_reg_readdata(ace, reg) in_be16(ace->baseaddr + reg)
+#define ace_reg_read32(ace, reg) ((in_le16(ace->baseaddr + reg+2) << 16) | \
+ (in_le16(ace->baseaddr + reg)))
+#define ace_reg_write16(ace, reg, val) out_le16(ace->baseaddr + reg, val)
+#define ace_reg_writedata(ace, reg, val) out_be16(ace->baseaddr + reg, val)
+#define ace_reg_write32(ace, reg, val) { \
+ out_le16(ace->baseaddr + reg+2, (val) >> 16); \
+ out_le16(ace->baseaddr + reg, val); \
+ }
+#else /* Big endian 16-bit regs */
+#define ace_reg_read8(ace, reg) in_8(ace->baseaddr + reg)
+#define ace_reg_read16(ace, reg) in_be16(ace->baseaddr + reg)
+#define ace_reg_readdata(ace, reg) in_le16(ace->baseaddr + reg)
+#define ace_reg_read32(ace, reg) ((in_be16(ace->baseaddr + reg+2) << 16) | \
+ (in_be16(ace->baseaddr + reg)))
+#define ace_reg_write16(ace, reg, val) out_be16(ace->baseaddr + reg, val)
+#define ace_reg_writedata(ace, reg, val) out_le16(ace->baseaddr + reg, val)
+#define ace_reg_write32(ace, reg, val) { \
+ out_be16(ace->baseaddr + reg+2, (val) >> 16); \
+ out_be16(ace->baseaddr + reg, val); \
+ }
+#endif
+
+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 */
+ uint16_t* 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 requests finish */
+ int in_irq;
+
+ /* Details of hardware device */
+ ulong physaddr;
+ void* baseaddr;
+ int irq;
+ int bus_width; /* 0 := 8 bit; 1 := 16 bit */
+ int lock_count;
+
+ /* Block device data structures */
+ spinlock_t lock;
+ struct device *dev;
+ struct request_queue *queue;
+ struct gendisk *gd;
+
+ /* Inserted CF card parameters */
+ struct hd_driveid cf_id;
+};
+
+static LIST_HEAD(ace_instances);
+static int ace_major = 0;
+
+/* ---------------------------------------------------------------------
+ * Debug support functions
+ */
+
+#define ace_dbg(ace, format, arg...) dev_dbg(ace->dev, format, ## arg)
+#define ace_err(ace, format, arg...) dev_err(ace->dev, format, ## arg)
+#define ace_info(ace, format, arg...) dev_info(ace->dev, format, ## arg)
+#define ace_warn(ace, format, arg...) dev_warn(ace->dev, format, ## arg)
+#define ace_notice(ace, format, arg...) dev_notice(ace->dev, format, ## arg)
+
+#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)
+{
+
+#if defined(DEBUG_ENDIAN)
+ /* some test routines to see if 8 16 and 32 bit access is working */
+ ace_info(ace, "register dump:"); /* No '\n' needed! */
+ {
+ int i;
+ for (i = 0; i < 0x20; i++) {
+ if (!(i % 16))
+ printk("\n" KERN_INFO " %.2x:", i);
+ printk(" %.2x", ace_reg_read8(ace, i));
+ }
+ for (i = 0; i < 0x20; i+=2) {
+ if (!(i % 16))
+ printk("\n" KERN_INFO " %.2x:", i);
+ printk(" %.4x ", ace_reg_read16(ace, i));
+ }
+ for (i = 0; i < 0x20; i+=4) {
+ if (!(i % 16))
+ printk("\n" KERN_INFO " %.2x:", i);
+ printk(" %.8x ", ace_reg_read32(ace, i));
+ }
+ }
+ printk("\n");
+#endif
+
+ ace_info(ace, " 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_reg_read32(ace, ACE_CTRL),
+ ace_reg_read16(ace, ACE_SECCNTCMD),
+ ace_reg_read16(ace, ACE_VERSION),
+ ace_reg_read32(ace, ACE_STATUS),
+ ace_reg_read32(ace, ACE_MPULBA),
+ ace_reg_read16(ace, ACE_BUSMODE),
+ ace_reg_read32(ace, ACE_ERROR),
+ ace_reg_read32(ace, ACE_CFGLBA),
+ ace_reg_read16(ace, ACE_FATSTAT));
+}
+
+void ace_fix_driveid (struct hd_driveid *id)
+{
+#ifndef __LITTLE_ENDIAN
+# ifdef __BIG_ENDIAN
+ /* The ace_reg_read16 macro handles 16 bit reads correctly, but
+ * 32bit values are partially little endian; swap the words
+ */
+ id->lba_capacity = ((id->lba_capacity >> 16) & 0x0000FFFF) |
+ ((id->lba_capacity << 16) & 0xFFFF0000);
+ id->spg = ((id->spg >> 16) & 0x0000FFFF) |
+ ((id->spg << 16) & 0xFFFF0000);
+# else
+# error "Please fix <asm/byteorder.h>"
+# endif
+#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_NUM_STATES 10
+
+#if defined(DEBUG)
+const char* ace_statenames[ACE_FSM_NUM_STATES] = {
+ "idle",
+ "req lock",
+ "wait lock",
+ "wait cf ready",
+ "identify prepare",
+ "identify transfer",
+ "identify complete",
+ "request prepare",
+ "request transfer",
+ "request complete",
+};
+#endif
+
+/* Set flag to exit FSM loop and reschedule tasklet */
+static void inline ace_fsm_yield(struct ace_device *ace)
+{
+ ace_dbg(ace, "ace_fsm_yield()\n");
+ tasklet_schedule(&ace->fsm_tasklet);
+ ace->fsm_continue_flag = 0;
+}
+
+/* Set flag to exit FSM loop and wait for IRQ to reschedule tasklet */
+static void inline ace_fsm_yieldirq(struct ace_device *ace)
+{
+ ace_dbg(ace, "ace_fsm_yieldirq()\n");
+ ace->fsm_continue_flag = 0;
+}
+
+/* Get the next read/write request; ending requests that we don't handle */
+struct request* ace_get_next_request(request_queue_t *q)
+{
+ struct request *req;
+
+ while ((req = elv_next_request(q)) != NULL) {
+ if (blk_fs_request(req))
+ break;
+ end_request(req, 0);
+ }
+ return req;
+}
+
+static void ace_fsm_dostate(struct ace_device *ace)
+{
+ struct request *req;
+ uint32_t status;
+ uint16_t val;
+ int count;
+ int i;
+
+#if defined(DEBUG)
+ const char *name = "invalid";
+ if (ace->fsm_state < ACE_FSM_NUM_STATES)
+ name = ace_statenames[ace->fsm_state];
+ ace_info(ace, "fsm_state=%i \"%s\", id_req_count=%i\n",
+ ace->fsm_state, name, ace->id_req_count);
+#endif
+
+ switch (ace->fsm_state) {
+ case ACE_FSM_STATE_IDLE:
+ /* See if there is anything to do */
+ if (ace->id_req_count || ace_get_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_reg_read16(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_reg_read16(ace, ACE_CTRL);
+ ace_reg_write16(ace, ACE_CTRL, val | ACE_CTRL_LOCKREQ);
+ ace->fsm_state = ACE_FSM_STATE_WAIT_LOCK;
+ break;
+
+ case ACE_FSM_STATE_WAIT_LOCK:
+ if (ace_reg_read16(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_reg_read32(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 = (void*)&ace->cf_id;
+ ace->data_count = ACE_BUF_PER_SECTOR;
+ ace_reg_write16(ace, ACE_SECCNTCMD, ACE_SECCNTCMD_IDENTIFY);
+
+ /* As per datasheet, put config controller in reset */
+ val = ace_reg_read16(ace, ACE_CTRL);
+ ace_reg_write16(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_reg_read32(ace, ACE_STATUS);
+ if (status & ACE_STATUS_CFBSY) {
+ ace_dbg(ace, "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 */
+ i = 16;
+ while (i--)
+ *ace->data_ptr++ = ace_reg_read16(ace, 0x40);
+ 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 */
+ ace_dbg(ace, "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 occured, disable the disk */
+ ace->media_change = 1;
+ set_capacity(ace->gd, 0);
+ ace_err(ace, "error fetching CF id (%i)\n",
+ ace->data_result);
+ } else {
+ ace->media_change = 0;
+
+ /* Record disk parameters */
+ set_capacity(ace->gd, ace->cf_id.lba_capacity);
+ ace_info(ace, "capacity: %i sectors\n",
+ ace->cf_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 */
+ ace_dbg(ace, "request: sec=%lx hcnt=%lx, ccnt=%x, dir=%i\n",
+ req->sector, req->hard_nr_sectors,
+ req->current_nr_sectors, rq_data_dir(req));
+
+ ace->req = req;
+ ace->data_ptr = (void*)req->buffer;
+ ace->data_count = req->current_nr_sectors * ACE_BUF_PER_SECTOR;
+ ace_reg_write32(ace, ACE_MPULBA, req->sector & 0x0FFFFFFF);
+
+ count = req->hard_nr_sectors;
+ if (rq_data_dir(req)) {
+ /* Kick off write request */
+ ace_dbg(ace, "write data\n");
+ ace->fsm_task = ACE_TASK_WRITE;
+ ace_reg_write16(ace, ACE_SECCNTCMD,
+ count | ACE_SECCNTCMD_WRITE_DATA);
+ } else {
+ /* Kick off read request */
+ ace_dbg(ace, "read data\n");
+ ace->fsm_task = ACE_TASK_READ;
+ ace_reg_write16(ace, ACE_SECCNTCMD,
+ count | ACE_SECCNTCMD_READ_DATA);
+ }
+
+ /* As per datasheet, put config controller in reset */
+ val = ace_reg_read16(ace, ACE_CTRL);
+ ace_reg_write16(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_reg_read32(ace, ACE_STATUS);
+ if (status & ACE_STATUS_CFBSY) {
+ ace_dbg(ace, "CFBSY set; t=%i iter=%i c=%i dc=%i irq=%i\n",
+ ace->fsm_task, ace->fsm_iter_num,
+ ace->req->current_nr_sectors*16,
+ ace->data_count, ace->in_irq);
+ ace_fsm_yield(ace); /* need to poll CFBSY bit */
+ break;
+ }
+ if (!(status & ACE_STATUS_DATABUFRDY)) {
+ ace_dbg(ace, "DATABUF not set; t=%i iter=%i c=%i dc=%i irq=%i\n",
+ ace->fsm_task, ace->fsm_iter_num,
+ ace->req->current_nr_sectors*16,
+ ace->data_count, ace->in_irq);
+ ace_fsm_yieldirq(ace);
+ break;
+ }
+
+ /* Transfer the next buffer */
+ i = 16;
+ if (ace->fsm_task == ACE_TASK_WRITE)
+ while (i--)
+ ace_reg_writedata(ace, 0x40, *ace->data_ptr++);
+ else
+ while (i--)
+ *ace->data_ptr++ = ace_reg_readdata(ace, 0x40);
+ 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? */
+ i = ace->req->current_nr_sectors;
+ if (end_that_request_first(ace->req, 1, i)) {
+ /* ace_dbg(ace, "next block; h=%li c=%i\n",
+ * ace->req->hard_nr_sectors,
+ * ace->req->current_nr_sectors);
+ */
+ ace->data_ptr = (void*)ace->req->buffer;
+ ace->data_count = ace->req->current_nr_sectors * 16;
+ ace_fsm_yieldirq(ace);
+ break;
+ }
+
+ ace->fsm_state = ACE_FSM_STATE_REQ_COMPLETE;
+ break;
+
+ case ACE_FSM_STATE_REQ_COMPLETE:
+ /* Complete the block request */
+ blkdev_dequeue_request(ace->req);
+ end_that_request_last(ace->req, 1);
+ 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(ulong 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(ulong data)
+{
+ struct ace_device *ace = (void*)data;
+ unsigned long flags;
+
+ ace_warn(ace, "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);
+
+ /* Loop over state machine until told to stop */
+ ace->fsm_continue_flag = 1;
+ while (ace->fsm_continue_flag)
+ ace_fsm_dostate(ace);
+
+ /* Rearm the stall timer */
+ ace->stall_timer.expires = jiffies + HZ;
+ add_timer(&ace->stall_timer);
+
+ spin_unlock_irqrestore(&ace->lock, flags);
+}
+
+/* ---------------------------------------------------------------------
+ * Interrupt handling routines
+ */
+static int ace_interrupt_checkstate(struct ace_device *ace)
+{
+ uint32_t sreg = ace_reg_read32(ace, ACE_STATUS);
+ uint16_t creg = ace_reg_read16(ace, ACE_CTRL);
+
+ /* Check for error occurance */
+ if ((sreg & (ACE_STATUS_CFGERROR | ACE_STATUS_CFCERROR)) &&
+ (creg & ACE_CTRL_ERRORIRQ)) {
+ ace_err(ace, "transfer failure\n");
+ ace_dump_regs(ace);
+ return -EIO;
+ }
+
+ return 0;
+}
+
+static irqreturn_t ace_interrupt(int irq, void *dev_id)
+{
+ uint16_t creg;
+ struct ace_device *ace = dev_id;
+ unsigned long flags;
+
+ /* be safe and get the lock */
+ spin_lock_irqsave(&ace->lock, flags);
+ ace->in_irq = 1;
+
+ /* clear the interrupt */
+ creg = ace_reg_read16(ace, ACE_CTRL);
+ ace_reg_write16(ace, ACE_CTRL, creg | ACE_CTRL_RESETIRQ);
+ ace_reg_write16(ace, ACE_CTRL, creg);
+
+ /* check for IO failures */
+ if (ace_interrupt_checkstate(ace))
+ ace->data_result = -EIO;
+
+ if (ace->fsm_task == 0) {
+ ace_err(ace, "spurious irq; stat=%.8x ctrl=%.8x cmd=%.4x\n",
+ ace_reg_read32(ace, ACE_STATUS),
+ ace_reg_read32(ace, ACE_CTRL),
+ ace_reg_read16(ace, ACE_SECCNTCMD));
+ ace_err(ace, "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_irqrestore(&ace->lock, flags);
+
+ return IRQ_HANDLED;
+}
+
+/* ---------------------------------------------------------------------
+ * Block ops
+ */
+static void ace_request(request_queue_t *q)
+{
+ struct request *req;
+ struct ace_device *ace;
+
+ req = ace_get_next_request(q);
+
+ if (req) {
+ ace = req->rq_disk->private_data;
+ tasklet_schedule(&ace->fsm_tasklet);
+ }
+}
+
+static int ace_media_changed(struct gendisk *gd)
+{
+ struct ace_device *ace = gd->private_data;
+ ace_dbg(ace, "ace_media_changed(): %i\n", ace->media_change);
+
+ return ace->media_change;
+}
+
+static int ace_revalidate_disk(struct gendisk *gd)
+{
+ struct ace_device *ace = gd->private_data;
+ ulong flags;
+
+ ace_dbg(ace, "ace_revalidate_disk()\n");
+
+ if (ace->media_change) {
+ ace_dbg(ace, "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);
+ }
+
+ ace_dbg(ace, "revalidate complete\n");
+ return ace->id_result;
+}
+
+static int ace_open(struct inode *inode, struct file *filp)
+{
+ struct ace_device *ace = inode->i_bdev->bd_disk->private_data;
+ unsigned long flags;
+
+ ace_dbg(ace, "ace_open() users=%i\n", ace->users+1);
+
+ filp->private_data = ace;
+ spin_lock_irqsave(&ace->lock, flags);
+ ace->users++;
+ spin_unlock_irqrestore(&ace->lock, flags);
+
+ check_disk_change(inode->i_bdev);
+ return 0;
+}
+
+static int ace_release(struct inode *inode, struct file *filp)
+{
+ struct ace_device *ace = inode->i_bdev->bd_disk->private_data;
+ unsigned long flags;
+ uint16_t val;
+
+ ace_dbg(ace, "ace_release() users=%i\n", ace->users-1);
+
+ spin_lock_irqsave(&ace->lock, flags);
+ ace->users--;
+ if (ace->users == 0) {
+ val = ace_reg_read16(ace, ACE_CTRL);
+ ace_reg_write16(ace, ACE_CTRL, val & ~ACE_CTRL_LOCKREQ);
+ }
+ spin_unlock_irqrestore(&ace->lock, flags);
+ return 0;
+}
+
+static int ace_ioctl(struct inode *inode, struct file *filp,
+ unsigned int cmd, unsigned long arg)
+{
+ struct ace_device *ace = inode->i_bdev->bd_disk->private_data;
+ ace_dbg(ace, "ace_ioctl()\n");
+
+ return -ENOTTY;
+}
+
+static struct block_device_operations ace_fops = {
+ .owner = THIS_MODULE,
+ .open = ace_open,
+ .release = ace_release,
+ .media_changed = ace_media_changed,
+ .revalidate_disk = ace_revalidate_disk,
+ .ioctl = ace_ioctl,
+};
+
+/* --------------------------------------------------------------------
+ * SystemACE device setup/teardown code
+ */
+static int ace_setup(struct ace_device *ace)
+{
+ uint16_t version;
+ uint16_t val;
+ int rc;
+
+ spin_lock_init(&ace->lock);
+ init_completion(&ace->id_completion);
+
+ /*
+ * Map the device
+ */
+ ace->baseaddr = ioremap(ace->physaddr, 0x80);
+ if (!ace->baseaddr)
+ goto err_ioremap;
+
+ if (ace->irq != NO_IRQ) {
+ rc = request_irq(ace->irq, ace_interrupt, 0, "systemace", ace);
+ if (rc) {
+ /* Failure - fall back to polled mode */
+ ace_err(ace, "request_irq failed\n");
+ ace->irq = NO_IRQ;
+ }
+ }
+
+ /*
+ * Initialize the state machine tasklet and stall timer
+ */
+ tasklet_init(&ace->fsm_tasklet, ace_fsm_tasklet, (ulong)ace);
+ init_timer(&ace->stall_timer);
+ ace->stall_timer.function = ace_stall_timer;
+ ace->stall_timer.data = (ulong)ace;
+
+ /*
+ * Initialize the request queue
+ */
+ ace->queue = blk_init_queue(ace_request, &ace->lock);
+ if (ace->queue == NULL)
+ goto err_blk_initq;
+ blk_queue_hardsect_size(ace->queue, 512);
+
+ /*
+ * 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->queue = ace->queue;
+ ace->gd->private_data = ace;
+ snprintf(ace->gd->disk_name, 32, "xs%c", ace->id + 'a');
+ device_rename(ace->dev, ace->gd->disk_name);
+
+ /* set 16-bit bus width */
+ ace_reg_write16(ace, ACE_BUSMODE, 0x0001);
+
+ /* Make sure version register is sane */
+ version = ace_reg_read16(ace, ACE_VERSION);
+ if ((version == 0) || (version == 0xFFFF))
+ goto err_read;
+
+ /* Put sysace in a sane state by clearing most control reg bits */
+ ace_reg_write16(ace, ACE_CTRL, ACE_CTRL_FORCECFGMODE |
+ ACE_CTRL_DATABUFRDYIRQ |
+ ACE_CTRL_ERRORIRQ);
+
+ /* Enable interrupts */
+ val = ace_reg_read16(ace, ACE_CTRL);
+ val |= ACE_CTRL_DATABUFRDYIRQ | ACE_CTRL_ERRORIRQ;
+ ace_reg_write16(ace, ACE_CTRL, val);
+
+ /* Print the identification */
+ ace_info(ace, "Xilinx SystemACE revision %i.%i.%i\n",
+ (version>>12)&0xf, (version>>8)&0x0f, version&0xff);
+ ace_dbg(ace, "physaddr 0x%lx, mapped to 0x%p, irq=%i\n",
+ ace->physaddr, ace->baseaddr, ace->irq);
+
+ ace->media_change = 1;
+ ace_revalidate_disk(ace->gd);
+
+ /* Make the sysace device 'live' */
+ list_add(&ace->list, &ace_instances);
+ add_disk(ace->gd);
+
+ return 0;
+
+err_read:
+ put_disk(ace->gd);
+err_alloc_disk:
+ blk_cleanup_queue(ace->queue);
+err_blk_initq:
+ iounmap(ace->baseaddr);
+ if (ace->irq != NO_IRQ)
+ free_irq(ace->irq, ace);
+err_ioremap:
+ printk(KERN_INFO "xsysace: error initializing device at 0x%lx\n",
+ 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);
+
+ tasklet_kill(&ace->fsm_tasklet);
+
+ if (ace->irq != NO_IRQ)
+ free_irq(ace->irq, ace);
+
+ iounmap(ace->baseaddr);
+}
+
+/* ---------------------------------------------------------------------
+ * Platform Bus Support
+ */
+
+static int ace_probe(struct device *device)
+{
+ struct platform_device *dev = to_platform_device(device);
+ struct ace_device *ace;
+ int i;
+
+ dev_dbg(device, "ace_probe(%p)\n", device);
+
+ /*
+ * Allocate the ace device structure
+ */
+ ace = kmalloc(sizeof(struct ace_device), GFP_KERNEL);
+ if (!ace)
+ goto err_alloc;
+ memset(ace, 0, sizeof(struct ace_device));
+
+ ace->dev = device;
+ ace->id = dev->id;
+ ace->irq = NO_IRQ;
+
+ for (i = 0; i < dev->num_resources; i++) {
+ if (dev->resource[i].flags & IORESOURCE_MEM)
+ ace->physaddr = dev->resource[i].start;
+ if (dev->resource[i].flags & IORESOURCE_IRQ)
+ ace->irq = dev->resource[i].start;
+ }
+
+ dev_set_drvdata(&dev->dev, ace);
+
+ /* Call the bus-independant setup code */
+ if (ace_setup(ace) != 0)
+ goto err_setup;
+
+ return 0;
+
+err_setup:
+ dev_set_drvdata(&dev->dev, NULL);
+ kfree(ace);
+err_alloc:
+ printk(KERN_ERR "xsysace: could not initialize device\n");
+ return -ENOMEM;
+}
+
+/*
+ * Platform bus remove() method
+ */
+static int ace_remove(struct device *device)
+{
+ struct ace_device *ace = dev_get_drvdata(device);
+
+ dev_dbg(device, "ace_remove(%p)\n", device);
+
+ if (ace) {
+ ace_teardown(ace);
+ kfree(ace);
+ }
+
+ return 0;
+}
+
+static struct device_driver ace_driver = {
+ .name = "xsysace",
+ .bus = &platform_bus_type,
+ .probe = ace_probe,
+ .remove = ace_remove,
+};
+
+/* ---------------------------------------------------------------------
+ * Module init/exit routines
+ */
+static int __init ace_init(void)
+{
+ ace_major = register_blkdev(ace_major, "xsysace");
+ if (ace_major <= 0) {
+ printk(KERN_WARNING "xsysace: register_blkdev() failed\n");
+ return ace_major;
+ }
+
+ pr_debug("Registering Xilinx SystemACE driver, major=%i\n", ace_major);
+ return driver_register(&ace_driver);
+}
+
+static void __exit ace_exit(void)
+{
+ pr_debug("Unregistering Xilinx SystemACE driver\n");
+ driver_unregister(&ace_driver);
+ if (unregister_blkdev(ace_major, "xsysace"))
+ printk(KERN_WARNING "systemace unregister_blkdev(%i) failed\n",
+ ace_major);
+}
+
+module_init(ace_init);
+module_exit(ace_exit);
--
1.5.1
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