Merge branch 'ipa-cleanups'

Alex Elder says:

====================
net: ipa: some more cleanup

Version 3 of this series uses dev_err_probe() in the second patch,
as suggested by Heiner Kallweit.

Version 2 was sent to ensure the series was based on current
net-next/master, and added copyright updates to files touched.

The original introduction is below.

This is another fairly innocuous set of cleanup patches.

The first was motivated by a bug found that would affect IPA v4.5.
It maintain a new GSI address pointer; one is the "raw" (original
mapped) address, and the other will have been adjusted if necessary
for use on newer platforms.

The second just quiets some unnecessary noise during early probe.

The third fixes some errors that show up when IPA_VALIDATION is
enabled.

The last two just create helper functions to improve readability.

====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 26 insertions, 24 deletions

diff --git a/drivers/net/ipa/gsi.c b/drivers/net/ipa/gsi.c
index 440213646188..390d3403386a 100644
--- a/drivers/net/ipa/gsi.c
+++ b/drivers/net/ipa/gsi.c
@@ -1,7 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0
 
 /* Copyright (c) 2015-2018, The Linux Foundation. All rights reserved.
- * Copyright (C) 2018-2020 Linaro Ltd.
+ * Copyright (C) 2018-2021 Linaro Ltd.
  */
 
 #include <linux/types.h>
@@ -175,6 +175,12 @@ static u32 gsi_channel_id(struct gsi_channel *channel)
 	return channel - &channel->gsi->channel[0];
 }
 
+/* An initialized channel has a non-null GSI pointer */
+static bool gsi_channel_initialized(struct gsi_channel *channel)
+{
+	return !!channel->gsi;
+}
+
 /* Update the GSI IRQ type register with the cached value */
 static void gsi_irq_type_update(struct gsi *gsi, u32 val)
 {
@@ -195,8 +201,6 @@ static void gsi_irq_type_disable(struct gsi *gsi, enum gsi_irq_type_id type_id)
 /* Turn off all GSI interrupts initially */
 static void gsi_irq_setup(struct gsi *gsi)
 {
-	u32 adjust;
-
 	/* Disable all interrupt types */
 	gsi_irq_type_update(gsi, 0);
 
@@ -206,10 +210,9 @@ static void gsi_irq_setup(struct gsi *gsi)
 	iowrite32(0, gsi->virt + GSI_CNTXT_GLOB_IRQ_EN_OFFSET);
 	iowrite32(0, gsi->virt + GSI_CNTXT_SRC_IEOB_IRQ_MSK_OFFSET);
 
-	/* Reverse the offset adjustment for inter-EE register offsets */
-	adjust = gsi->version < IPA_VERSION_4_5 ? 0 : GSI_EE_REG_ADJUST;
-	iowrite32(0, gsi->virt + adjust + GSI_INTER_EE_SRC_CH_IRQ_OFFSET);
-	iowrite32(0, gsi->virt + adjust + GSI_INTER_EE_SRC_EV_CH_IRQ_OFFSET);
+	/* The inter-EE registers are in the non-adjusted address range */
+	iowrite32(0, gsi->virt_raw + GSI_INTER_EE_SRC_CH_IRQ_OFFSET);
+	iowrite32(0, gsi->virt_raw + GSI_INTER_EE_SRC_EV_CH_IRQ_OFFSET);
 
 	iowrite32(0, gsi->virt + GSI_CNTXT_GSI_IRQ_EN_OFFSET);
 }
@@ -1641,8 +1644,8 @@ static int gsi_channel_setup_one(struct gsi *gsi, u32 channel_id)
 	u32 evt_ring_id = channel->evt_ring_id;
 	int ret;
 
-	if (!channel->gsi)
-		return 0;	/* Ignore uninitialized channels */
+	if (!gsi_channel_initialized(channel))
+		return 0;
 
 	ret = gsi_evt_ring_alloc_command(gsi, evt_ring_id);
 	if (ret)
@@ -1678,8 +1681,8 @@ static void gsi_channel_teardown_one(struct gsi *gsi, u32 channel_id)
 	struct gsi_channel *channel = &gsi->channel[channel_id];
 	u32 evt_ring_id = channel->evt_ring_id;
 
-	if (!channel->gsi)
-		return;		/* Ignore uninitialized channels */
+	if (!gsi_channel_initialized(channel))
+		return;
 
 	netif_napi_del(&channel->napi);
 
@@ -1773,8 +1776,8 @@ static int gsi_channel_setup(struct gsi *gsi)
 	while (channel_id < GSI_CHANNEL_COUNT_MAX) {
 		struct gsi_channel *channel = &gsi->channel[channel_id++];
 
-		if (!channel->gsi)
-			continue;	/* Ignore uninitialized channels */
+		if (!gsi_channel_initialized(channel))
+			continue;
 
 		ret = -EINVAL;
 		dev_err(gsi->dev, "channel %u not supported by hardware\n",
@@ -2092,8 +2095,8 @@ err_clear_gsi:
 /* Inverse of gsi_channel_init_one() */
 static void gsi_channel_exit_one(struct gsi_channel *channel)
 {
-	if (!channel->gsi)
-		return;		/* Ignore uninitialized channels */
+	if (!gsi_channel_initialized(channel))
+		return;
 
 	if (channel->command)
 		ipa_cmd_pool_exit(channel);
@@ -2181,9 +2184,8 @@ int gsi_init(struct gsi *gsi, struct platform_device *pdev,
 	gsi->dev = dev;
 	gsi->version = version;
 
-	/* The GSI layer performs NAPI on all endpoints.  NAPI requires a
-	 * network device structure, but the GSI layer does not have one,
-	 * so we must create a dummy network device for this purpose.
+	/* GSI uses NAPI on all channels.  Create a dummy network device
+	 * for the channel NAPI contexts to be associated with.
 	 */
 	init_dummy_netdev(&gsi->dummy_dev);
 
@@ -2208,13 +2210,13 @@ int gsi_init(struct gsi *gsi, struct platform_device *pdev,
 		return -EINVAL;
 	}
 
-	gsi->virt = ioremap(res->start, size);
-	if (!gsi->virt) {
+	gsi->virt_raw = ioremap(res->start, size);
+	if (!gsi->virt_raw) {
 		dev_err(dev, "unable to remap \"gsi\" memory\n");
 		return -ENOMEM;
 	}
-	/* Adjust register range pointer downward for newer IPA versions */
-	gsi->virt -= adjust;
+	/* Most registers are accessed using an adjusted register range */
+	gsi->virt = gsi->virt_raw - adjust;
 
 	init_completion(&gsi->completion);
 
@@ -2233,7 +2235,7 @@ int gsi_init(struct gsi *gsi, struct platform_device *pdev,
 err_irq_exit:
 	gsi_irq_exit(gsi);
 err_iounmap:
-	iounmap(gsi->virt);
+	iounmap(gsi->virt_raw);
 
 	return ret;
 }
@@ -2244,7 +2246,7 @@ void gsi_exit(struct gsi *gsi)
 	mutex_destroy(&gsi->mutex);
 	gsi_channel_exit(gsi);
 	gsi_irq_exit(gsi);
-	iounmap(gsi->virt);
+	iounmap(gsi->virt_raw);
 }
 
 /* The maximum number of outstanding TREs on a channel.  This limits