1 files changed, 106 insertions, 48 deletions

diff --git a/arch/powerpc/platforms/powernv/opal.c b/arch/powerpc/platforms/powernv/opal.c
index 0d539c661748..404c379db168 100644
--- a/arch/powerpc/platforms/powernv/opal.c
+++ b/arch/powerpc/platforms/powernv/opal.c
@@ -344,70 +344,125 @@ int opal_get_chars(uint32_t vtermno, char *buf, int count)
 	return 0;
 }
 
-int opal_put_chars(uint32_t vtermno, const char *data, int total_len)
+static int __opal_put_chars(uint32_t vtermno, const char *data, int total_len, bool atomic)
 {
-	int written = 0;
+	unsigned long flags = 0 /* shut up gcc */;
+	int written;
 	__be64 olen;
-	s64 len, rc;
-	unsigned long flags;
-	__be64 evt;
+	s64 rc;
 
 	if (!opal.entry)
 		return -ENODEV;
 
-	/* We want put_chars to be atomic to avoid mangling of hvsi
-	 * packets. To do that, we first test for room and return
-	 * -EAGAIN if there isn't enough.
-	 *
-	 * Unfortunately, opal_console_write_buffer_space() doesn't
-	 * appear to work on opal v1, so we just assume there is
-	 * enough room and be done with it
-	 */
-	spin_lock_irqsave(&opal_write_lock, flags);
+	if (atomic)
+		spin_lock_irqsave(&opal_write_lock, flags);
 	rc = opal_console_write_buffer_space(vtermno, &olen);
-	len = be64_to_cpu(olen);
-	if (rc || len < total_len) {
-		spin_unlock_irqrestore(&opal_write_lock, flags);
+	if (rc || be64_to_cpu(olen) < total_len) {
 		/* Closed -> drop characters */
 		if (rc)
-			return total_len;
-		opal_poll_events(NULL);
-		return -EAGAIN;
+			written = total_len;
+		else
+			written = -EAGAIN;
+		goto out;
 	}
 
-	/* We still try to handle partial completions, though they
-	 * should no longer happen.
-	 */
-	rc = OPAL_BUSY;
-	while(total_len > 0 && (rc == OPAL_BUSY ||
-				rc == OPAL_BUSY_EVENT || rc == OPAL_SUCCESS)) {
-		olen = cpu_to_be64(total_len);
-		rc = opal_console_write(vtermno, &olen, data);
-		len = be64_to_cpu(olen);
-
-		/* Closed or other error drop */
-		if (rc != OPAL_SUCCESS && rc != OPAL_BUSY &&
-		    rc != OPAL_BUSY_EVENT) {
-			written = total_len;
-			break;
+	/* Should not get a partial write here because space is available. */
+	olen = cpu_to_be64(total_len);
+	rc = opal_console_write(vtermno, &olen, data);
+	if (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) {
+		if (rc == OPAL_BUSY_EVENT) {
+			mdelay(OPAL_BUSY_DELAY_MS);
+			opal_poll_events(NULL);
+		} else if (rc == OPAL_BUSY_EVENT) {
+			mdelay(OPAL_BUSY_DELAY_MS);
 		}
-		if (rc == OPAL_SUCCESS) {
-			total_len -= len;
-			data += len;
-			written += len;
+		written = -EAGAIN;
+		goto out;
+	}
+
+	/* Closed or other error drop */
+	if (rc != OPAL_SUCCESS) {
+		written = opal_error_code(rc);
+		goto out;
+	}
+
+	written = be64_to_cpu(olen);
+	if (written < total_len) {
+		if (atomic) {
+			/* Should not happen */
+			pr_warn("atomic console write returned partial "
+				"len=%d written=%d\n", total_len, written);
 		}
-		/* This is a bit nasty but we need that for the console to
-		 * flush when there aren't any interrupts. We will clean
-		 * things a bit later to limit that to synchronous path
-		 * such as the kernel console and xmon/udbg
+		if (!written)
+			written = -EAGAIN;
+	}
+
+out:
+	if (atomic)
+		spin_unlock_irqrestore(&opal_write_lock, flags);
+
+	/* In the -EAGAIN case, callers loop, so we have to flush the console
+	 * here in case they have interrupts off (and we don't want to wait
+	 * for async flushing if we can make immediate progress here). If
+	 * necessary the API could be made entirely non-flushing if the
+	 * callers had a ->flush API to use.
+	 */
+	if (written == -EAGAIN)
+		opal_flush_console(vtermno);
+
+	return written;
+}
+
+int opal_put_chars(uint32_t vtermno, const char *data, int total_len)
+{
+	return __opal_put_chars(vtermno, data, total_len, false);
+}
+
+/*
+ * opal_put_chars_atomic will not perform partial-writes. Data will be
+ * atomically written to the terminal or not at all. This is not strictly
+ * true at the moment because console space can race with OPAL's console
+ * writes.
+ */
+int opal_put_chars_atomic(uint32_t vtermno, const char *data, int total_len)
+{
+	return __opal_put_chars(vtermno, data, total_len, true);
+}
+
+int opal_flush_console(uint32_t vtermno)
+{
+	s64 rc;
+
+	if (!opal_check_token(OPAL_CONSOLE_FLUSH)) {
+		__be64 evt;
+
+		WARN_ONCE(1, "opal: OPAL_CONSOLE_FLUSH missing.\n");
+		/*
+		 * If OPAL_CONSOLE_FLUSH is not implemented in the firmware,
+		 * the console can still be flushed by calling the polling
+		 * function while it has OPAL_EVENT_CONSOLE_OUTPUT events.
 		 */
-		do
+		do {
 			opal_poll_events(&evt);
-		while(rc == OPAL_SUCCESS &&
-			(be64_to_cpu(evt) & OPAL_EVENT_CONSOLE_OUTPUT));
+		} while (be64_to_cpu(evt) & OPAL_EVENT_CONSOLE_OUTPUT);
+
+		return OPAL_SUCCESS;
 	}
-	spin_unlock_irqrestore(&opal_write_lock, flags);
-	return written;
+
+	do  {
+		rc = OPAL_BUSY;
+		while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) {
+			rc = opal_console_flush(vtermno);
+			if (rc == OPAL_BUSY_EVENT) {
+				mdelay(OPAL_BUSY_DELAY_MS);
+				opal_poll_events(NULL);
+			} else if (rc == OPAL_BUSY) {
+				mdelay(OPAL_BUSY_DELAY_MS);
+			}
+		}
+	} while (rc == OPAL_PARTIAL); /* More to flush */
+
+	return opal_error_code(rc);
 }
 
 static int opal_recover_mce(struct pt_regs *regs,
@@ -922,6 +977,7 @@ EXPORT_SYMBOL_GPL(opal_flash_read);
 EXPORT_SYMBOL_GPL(opal_flash_write);
 EXPORT_SYMBOL_GPL(opal_flash_erase);
 EXPORT_SYMBOL_GPL(opal_prd_msg);
+EXPORT_SYMBOL_GPL(opal_check_token);
 
 /* Convert a region of vmalloc memory to an opal sg list */
 struct opal_sg_list *opal_vmalloc_to_sg_list(void *vmalloc_addr,
@@ -1034,3 +1090,5 @@ EXPORT_SYMBOL_GPL(opal_write_oppanel_async);
 EXPORT_SYMBOL_GPL(opal_int_set_mfrr);
 EXPORT_SYMBOL_GPL(opal_int_eoi);
 EXPORT_SYMBOL_GPL(opal_error_code);
+/* Export the below symbol for NX compression */
+EXPORT_SYMBOL(opal_nx_coproc_init);