From b054d4f9eb4b34c2187b89afb56e25b588618a9c Mon Sep 17 00:00:00 2001 From: Alex Elder Date: Thu, 5 Nov 2020 12:14:01 -0600 Subject: [PATCH] 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 Signed-off-by: Jakub Kicinski --- drivers/net/ipa/gsi.c | 39 ++++++++++++++++++++++++++++++++------- 1 file 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));