[MIPS] MT: Functional fixes and a little reformatting of APRP support

Signed-off-by: Kevin D. Kissell <kevink@mips.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/kernel/Makefile

@@ -56,9 +56,9 @@ obj-$(CONFIG_MIPS_MT_SMP)	+= smp-mt.o
 obj-$(CONFIG_MIPS_CMP)		+= smp-cmp.o
 obj-$(CONFIG_CPU_MIPSR2)	+= spram.o
 
-obj-$(CONFIG_MIPS_APSP_KSPD)	+= kspd.o
 obj-$(CONFIG_MIPS_VPE_LOADER)	+= vpe.o
 obj-$(CONFIG_MIPS_VPE_APSP_API)	+= rtlx.o
+obj-$(CONFIG_MIPS_APSP_KSPD)	+= kspd.o
 
 obj-$(CONFIG_I8259)		+= i8259.o
 obj-$(CONFIG_IRQ_CPU)		+= irq_cpu.o

arch/mips/kernel/kspd.c

@@ -257,7 +257,7 @@ void sp_work_handle_request(void)
 
 		vcwd = vpe_getcwd(tclimit);
 
- 		/* change to the cwd of the process that loaded the SP program */
+		/* change to cwd of the process that loaded the SP program */
 		old_fs = get_fs();
 		set_fs(KERNEL_DS);
 		sys_chdir(vcwd);
@@ -323,6 +323,9 @@ static void sp_cleanup(void)
 			set >>= 1;
 		}
 	}
+
+	/* Put daemon cwd back to root to avoid umount problems */
+	sys_chdir("/");
 }
 
 static int channel_open = 0;

arch/mips/kernel/rtlx.c

@@ -72,6 +72,15 @@ static void rtlx_dispatch(void)
 static irqreturn_t rtlx_interrupt(int irq, void *dev_id)
 {
 	int i;
+	unsigned int flags, vpeflags;
+
+	/* Ought not to be strictly necessary for SMTC builds */
+	local_irq_save(flags);
+	vpeflags = dvpe();
+	set_c0_status(0x100 << MIPS_CPU_RTLX_IRQ);
+	irq_enable_hazard();
+	evpe(vpeflags);
+	local_irq_restore(flags);
 
 	for (i = 0; i < RTLX_CHANNELS; i++) {
 			wake_up(&channel_wqs[i].lx_queue);
@@ -108,7 +117,8 @@ static void __used dump_rtlx(void)
 static int rtlx_init(struct rtlx_info *rtlxi)
 {
 	if (rtlxi->id != RTLX_ID) {
-		printk(KERN_ERR "no valid RTLX id at 0x%p 0x%lx\n", rtlxi, rtlxi->id);
+		printk(KERN_ERR "no valid RTLX id at 0x%p 0x%lx\n",
+			rtlxi, rtlxi->id);
 		return -ENOEXEC;
 	}
 
@@ -162,18 +172,17 @@ int rtlx_open(int index, int can_sleep)
 
 	if (rtlx == NULL) {
 		if( (p = vpe_get_shared(tclimit)) == NULL) {
-			if (can_sleep) {
+		    if (can_sleep) {
-				__wait_event_interruptible(channel_wqs[index].lx_queue,
+			__wait_event_interruptible(channel_wqs[index].lx_queue,
-				                           (p = vpe_get_shared(tclimit)),
+				(p = vpe_get_shared(tclimit)), ret);
-				                           ret);
+			if (ret)
-				if (ret)
-					goto out_fail;
-			} else {
-				printk(KERN_DEBUG "No SP program loaded, and device "
-					"opened with O_NONBLOCK\n");
-				ret = -ENOSYS;
 				goto out_fail;
-			}
+		    } else {
+			printk(KERN_DEBUG "No SP program loaded, and device "
+					"opened with O_NONBLOCK\n");
+			ret = -ENOSYS;
+			goto out_fail;
+		    }
 		}
 
 		smp_rmb();
@@ -182,7 +191,9 @@ int rtlx_open(int index, int can_sleep)
 				DEFINE_WAIT(wait);
 
 				for (;;) {
-					prepare_to_wait(&channel_wqs[index].lx_queue, &wait, TASK_INTERRUPTIBLE);
+					prepare_to_wait(
+						&channel_wqs[index].lx_queue,
+						&wait, TASK_INTERRUPTIBLE);
 					smp_rmb();
 					if (*p != NULL)
 						break;
@@ -195,7 +206,7 @@ int rtlx_open(int index, int can_sleep)
 				}
 				finish_wait(&channel_wqs[index].lx_queue, &wait);
 			} else {
-				printk(" *vpe_get_shared is NULL. "
+				pr_err(" *vpe_get_shared is NULL. "
 				       "Has an SP program been loaded?\n");
 				ret = -ENOSYS;
 				goto out_fail;
@@ -203,8 +214,9 @@ int rtlx_open(int index, int can_sleep)
 		}
 
 		if ((unsigned int)*p < KSEG0) {
-			printk(KERN_WARNING "vpe_get_shared returned an invalid pointer "
+			printk(KERN_WARNING "vpe_get_shared returned an "
-			       "maybe an error code %d\n", (int)*p);
+			       "invalid pointer maybe an error code %d\n",
+			       (int)*p);
 			ret = -ENOSYS;
 			goto out_fail;
 		}
@@ -232,6 +244,10 @@ out_ret:
 
 int rtlx_release(int index)
 {
+	if (rtlx == NULL) {
+		pr_err("rtlx_release() with null rtlx\n");
+		return 0;
+	}
 	rtlx->channel[index].lx_state = RTLX_STATE_UNUSED;
 	return 0;
 }
@@ -251,8 +267,8 @@ unsigned int rtlx_read_poll(int index, int can_sleep)
 			int ret = 0;
 
 			__wait_event_interruptible(channel_wqs[index].lx_queue,
-			                           chan->lx_read != chan->lx_write || sp_stopping,
+				(chan->lx_read != chan->lx_write) ||
-			                           ret);
+				sp_stopping, ret);
 			if (ret)
 				return ret;
 
@@ -282,7 +298,9 @@ static inline int write_spacefree(int read, int write, int size)
 unsigned int rtlx_write_poll(int index)
 {
 	struct rtlx_channel *chan = &rtlx->channel[index];
-	return write_spacefree(chan->rt_read, chan->rt_write, chan->buffer_size);
+
+	return write_spacefree(chan->rt_read, chan->rt_write,
+				chan->buffer_size);
 }
 
 ssize_t rtlx_read(int index, void __user *buff, size_t count)
@@ -344,8 +362,8 @@ ssize_t rtlx_write(int index, const void __user *buffer, size_t count)
 	rt_read = rt->rt_read;
 
 	/* total number of bytes to copy */
-	count = min(count,
+	count = min(count, (size_t)write_spacefree(rt_read, rt->rt_write,
-		    (size_t)write_spacefree(rt_read, rt->rt_write, rt->buffer_size));
+							rt->buffer_size));
 
 	/* first bit from write pointer to the end of the buffer, or count */
 	fl = min(count, (size_t) rt->buffer_size - rt->rt_write);
@@ -514,6 +532,11 @@ static int __init rtlx_module_init(void)
 
 	if (cpu_has_vint)
 		set_vi_handler(MIPS_CPU_RTLX_IRQ, rtlx_dispatch);
+	else {
+		pr_err("APRP RTLX init on non-vectored-interrupt processor\n");
+		err = -ENODEV;
+		goto out_chrdev;
+	}
 
 	rtlx_irq.dev_id = rtlx;
 	setup_irq(rtlx_irq_num, &rtlx_irq);

include/asm-mips/rtlx.h

@@ -29,13 +29,13 @@ extern unsigned int rtlx_read_poll(int index, int can_sleep);
 extern unsigned int rtlx_write_poll(int index);
 
 enum rtlx_state {
-	RTLX_STATE_UNUSED,
+	RTLX_STATE_UNUSED = 0,
 	RTLX_STATE_INITIALISED,
 	RTLX_STATE_REMOTE_READY,
 	RTLX_STATE_OPENED
 };
 
-#define RTLX_BUFFER_SIZE 1024
+#define RTLX_BUFFER_SIZE 2048
 
 /* each channel supports read and write.
    linux (vpe0) reads lx_buffer  and writes rt_buffer