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authorAlex Elder <elder@linaro.org>2020-11-05 21:14:01 +0300
committerJakub Kicinski <kuba@kernel.org>2020-11-08 02:39:16 +0300
commitb054d4f9eb4b34c2187b89afb56e25b588618a9c (patch)
tree959078b85f0ad45adb765dcf29d8273f6f5161fb /drivers
parent3ca97ffd984c477e6bba26a71ebba188b99f1a4c (diff)
downloadlinux-b054d4f9eb4b34c2187b89afb56e25b588618a9c.tar.xz
net: ipa: only enable GSI channel control IRQs when needed
A GSI channel causes a channel control interrupt to fire whenever its state changes (between NOT_ALLOCATED, ALLOCATED, STARTED, etc.). We do not support inter-EE channel commands (initiated by other EEs), so no channel should ever change state except when we request it to. Currently, we permit *all* channels to generate channel control interrupts--even those that are never used. And we enable channel control interrupts essentially at all times, from setup to teardown. Instead, disable all channel control interrupts initially in gsi_irq_setup(), and only enable the channel control interrupt type for the duration of a channel command. When doing so, only allow the channel being operated upon to cause the interrupt to fire. Because a channel's interrupt is now enabled only when needed (one channel at a time), there is no longer any need to zero the channel mask in gsi_irq_disable(). Add new gsi_irq_type_enable() and gsi_irq_type_disable() as helper functions to control whether a given GSI interrupt type is enabled. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/net/ipa/gsi.c39
1 files changed, 32 insertions, 7 deletions
diff --git a/drivers/net/ipa/gsi.c b/drivers/net/ipa/gsi.c
index f76b5a1e1f8d..4fc72dfe1e9b 100644
--- a/drivers/net/ipa/gsi.c
+++ b/drivers/net/ipa/gsi.c
@@ -237,11 +237,25 @@ static void gsi_irq_type_update(struct gsi *gsi)
gsi->virt + GSI_CNTXT_TYPE_IRQ_MSK_OFFSET);
}
+static void gsi_irq_type_enable(struct gsi *gsi, enum gsi_irq_type_id type_id)
+{
+ gsi->type_enabled_bitmap |= BIT(type_id);
+ gsi_irq_type_update(gsi);
+}
+
+static void gsi_irq_type_disable(struct gsi *gsi, enum gsi_irq_type_id type_id)
+{
+ gsi->type_enabled_bitmap &= ~BIT(type_id);
+ gsi_irq_type_update(gsi);
+}
+
/* Turn off all GSI interrupts initially */
static void gsi_irq_setup(struct gsi *gsi)
{
gsi->type_enabled_bitmap = 0;
gsi_irq_type_update(gsi);
+
+ iowrite32(0, gsi->virt + GSI_CNTXT_SRC_CH_IRQ_MSK_OFFSET);
}
/* Turn off all GSI interrupts when we're all done */
@@ -274,10 +288,6 @@ static void gsi_irq_enable(struct gsi *gsi)
{
u32 val;
- val = GENMASK(gsi->channel_count - 1, 0);
- iowrite32(val, gsi->virt + GSI_CNTXT_SRC_CH_IRQ_MSK_OFFSET);
- gsi->type_enabled_bitmap |= BIT(GSI_CH_CTRL);
-
val = GENMASK(gsi->evt_ring_count - 1, 0);
iowrite32(val, gsi->virt + GSI_CNTXT_SRC_EV_CH_IRQ_MSK_OFFSET);
gsi->type_enabled_bitmap |= BIT(GSI_EV_CTRL);
@@ -311,7 +321,6 @@ static void gsi_irq_disable(struct gsi *gsi)
iowrite32(0, gsi->virt + GSI_CNTXT_GLOB_IRQ_EN_OFFSET);
iowrite32(0, gsi->virt + GSI_CNTXT_SRC_IEOB_IRQ_MSK_OFFSET);
iowrite32(0, gsi->virt + GSI_CNTXT_SRC_EV_CH_IRQ_MSK_OFFSET);
- iowrite32(0, gsi->virt + GSI_CNTXT_SRC_CH_IRQ_MSK_OFFSET);
}
/* Return the virtual address associated with a ring index */
@@ -461,13 +470,29 @@ gsi_channel_command(struct gsi_channel *channel, enum gsi_ch_cmd_opcode opcode)
u32 channel_id = gsi_channel_id(channel);
struct gsi *gsi = channel->gsi;
struct device *dev = gsi->dev;
+ bool success;
u32 val;
+ /* We only perform one channel command at a time, and channel
+ * control interrupts should only occur when such a command is
+ * issued here. So we only permit *this* channel to trigger
+ * an interrupt and only enable the channel control IRQ type
+ * when we expect it to occur.
+ */
+ val = BIT(channel_id);
+ iowrite32(val, gsi->virt + GSI_CNTXT_SRC_CH_IRQ_MSK_OFFSET);
+ gsi_irq_type_enable(gsi, GSI_CH_CTRL);
+
val = u32_encode_bits(channel_id, CH_CHID_FMASK);
val |= u32_encode_bits(opcode, CH_OPCODE_FMASK);
+ success = gsi_command(gsi, GSI_CH_CMD_OFFSET, val, completion);
- if (gsi_command(gsi, GSI_CH_CMD_OFFSET, val, completion))
- return 0; /* Success! */
+ /* Disable the interrupt again */
+ gsi_irq_type_disable(gsi, GSI_CH_CTRL);
+ iowrite32(0, gsi->virt + GSI_CNTXT_SRC_CH_IRQ_MSK_OFFSET);
+
+ if (success)
+ return 0;
dev_err(dev, "GSI command %u for channel %u timed out, state %u\n",
opcode, channel_id, gsi_channel_state(channel));