diff --git a/drivers/net/ipa/gsi.c b/drivers/net/ipa/gsi.c
index 4402136461888..9c977f80109a9 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>
@@ -195,8 +195,6 @@ 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 +204,9 @@ 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);
}
@@ -2181,9 +2178,8 @@ 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 +2204,13 @@ 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 +2229,7 @@ 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 +2240,7 @@ 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
diff --git a/drivers/net/ipa/gsi.h b/drivers/net/ipa/gsi.h
index d674db0ba4eb0..efc980f96109e 100644
--- a/drivers/net/ipa/gsi.h
+++ b/drivers/net/ipa/gsi.h
@@ -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.
*/
#ifndef _GSI_H_
#define _GSI_H_
@@ -149,7 +149,8 @@ struct gsi {
struct device *dev; /* Same as IPA device */
enum ipa_version version;
struct net_device dummy_dev; /* needed for NAPI */
- void __iomem *virt;
+ void __iomem *virt_raw; /* I/O mapped address range */
+ void __iomem *virt; /* Adjusted for most registers */
u32 irq;
u32 channel_count;
u32 evt_ring_count;
diff --git a/drivers/net/ipa/gsi_reg.h b/drivers/net/ipa/gsi_reg.h
index 299456e70f286..1622d8cf8dea4 100644
--- a/drivers/net/ipa/gsi_reg.h
+++ b/drivers/net/ipa/gsi_reg.h
@@ -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.
*/
#ifndef _GSI_REG_H_
#define _GSI_REG_H_
@@ -38,17 +38,21 @@
* (though the actual limit is hardware-dependent).
*/
-/* GSI EE registers as a group are shifted downward by a fixed
- * constant amount for IPA versions 4.5 and beyond. This applies
- * to all GSI registers we use *except* the ones that disable
- * inter-EE interrupts for channels and event channels.
+/* GSI EE registers as a group are shifted downward by a fixed constant amount
+ * for IPA versions 4.5 and beyond. This applies to all GSI registers we use
+ * *except* the ones that disable inter-EE interrupts for channels and event
+ * channels.
*
- * We handle this by adjusting the pointer to the mapped GSI memory
- * region downward. Then in the one place we use them (gsi_irq_setup())
- * we undo that adjustment for the inter-EE interrupt registers.
+ * The "raw" (not adjusted) GSI register range is mapped, and a pointer to
+ * the mapped range is held in gsi->virt_raw. The inter-EE interrupt
+ * registers are accessed using that pointer.
+ *
+ * Most registers are accessed using gsi->virt, which is a copy of the "raw"
+ * pointer, adjusted downward by the fixed amount.
*/
#define GSI_EE_REG_ADJUST 0x0000d000 /* IPA v4.5+ */
+/* The two inter-EE IRQ register offsets are relative to gsi->virt_raw */
#define GSI_INTER_EE_SRC_CH_IRQ_OFFSET \
GSI_INTER_EE_N_SRC_CH_IRQ_OFFSET(GSI_EE_AP)
#define GSI_INTER_EE_N_SRC_CH_IRQ_OFFSET(ee) \
@@ -59,6 +63,7 @@
#define GSI_INTER_EE_N_SRC_EV_CH_IRQ_OFFSET(ee) \
(0x0000c01c + 0x1000 * (ee))
+/* All other register offsets are relative to gsi->virt */
#define GSI_CH_C_CNTXT_0_OFFSET(ch) \
GSI_EE_N_CH_C_CNTXT_0_OFFSET((ch), GSI_EE_AP)
#define GSI_EE_N_CH_C_CNTXT_0_OFFSET(ch, ee) \