From: Andrew Cooper <andrew.cooper3@citrix.com>
To: Jan Beulich <JBeulich@suse.com>
Cc: "suravee.suthikulpanit@amd.com" <suravee.suthikulpanit@amd.com>,
xen-devel <xen-devel@lists.xen.org>
Subject: Re: AMD/IOMMU: revert "SR56x0 Erratum 64 - Reset all head & tail pointers"
Date: Mon, 3 Jun 2013 10:43:28 +0100 [thread overview]
Message-ID: <51AC6540.9070101@citrix.com> (raw)
In-Reply-To: <51AC5DED02000078000DA6F4@nat28.tlf.novell.com>
On 03/06/13 08:12, Jan Beulich wrote:
> The code this patch added is redundant with already present code in
> set_iommu_{command_buffer,{event,ppr}_log}_control(). Just switch those
> ones from using writel() to writeq() for consistency.
>
> Signed-off-by: Jan Beulich <jbeulich@suse.com>
Yikes - I clearly didn't do a good job looking to see whether this issue
had already been addressed.
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
>
> --- a/xen/drivers/passthrough/amd/iommu_init.c
> +++ b/xen/drivers/passthrough/amd/iommu_init.c
> @@ -154,11 +154,6 @@ static void register_iommu_cmd_buffer_in
> IOMMU_CMD_BUFFER_LENGTH_MASK,
> IOMMU_CMD_BUFFER_LENGTH_SHIFT, &entry);
> writel(entry, iommu->mmio_base+IOMMU_CMD_BUFFER_BASE_HIGH_OFFSET);
> -
> - /* Reset head/tail pointer. SR56x0 Erratum 64 means this might not happen
> - * automatically for us. */
> - writeq(0, iommu->mmio_base + IOMMU_CMD_BUFFER_HEAD_OFFSET);
> - writeq(0, iommu->mmio_base + IOMMU_CMD_BUFFER_TAIL_OFFSET);
> }
>
> static void register_iommu_event_log_in_mmio_space(struct amd_iommu *iommu)
> @@ -187,11 +182,6 @@ static void register_iommu_event_log_in_
> IOMMU_EVENT_LOG_LENGTH_MASK,
> IOMMU_EVENT_LOG_LENGTH_SHIFT, &entry);
> writel(entry, iommu->mmio_base+IOMMU_EVENT_LOG_BASE_HIGH_OFFSET);
> -
> - /* Reset head/tail pointer. SR56x0 Erratum 64 means this might not happen
> - * automatically for us. */
> - writeq(0, iommu->mmio_base + IOMMU_EVENT_LOG_HEAD_OFFSET);
> - writeq(0, iommu->mmio_base + IOMMU_EVENT_LOG_TAIL_OFFSET);
> }
>
> static void register_iommu_ppr_log_in_mmio_space(struct amd_iommu *iommu)
> @@ -220,9 +210,6 @@ static void register_iommu_ppr_log_in_mm
> IOMMU_PPR_LOG_LENGTH_MASK,
> IOMMU_PPR_LOG_LENGTH_SHIFT, &entry);
> writel(entry, iommu->mmio_base + IOMMU_PPR_LOG_BASE_HIGH_OFFSET);
> -
> - writeq(0, iommu->mmio_base + IOMMU_PPR_LOG_HEAD_OFFSET);
> - writeq(0, iommu->mmio_base + IOMMU_PPR_LOG_TAIL_OFFSET);
> }
>
>
> @@ -267,8 +254,8 @@ static void set_iommu_command_buffer_con
> /*reset head and tail pointer manually before enablement */
> if ( enable )
> {
> - writel(0x0, iommu->mmio_base + IOMMU_CMD_BUFFER_HEAD_OFFSET);
> - writel(0x0, iommu->mmio_base + IOMMU_CMD_BUFFER_TAIL_OFFSET);
> + writeq(0, iommu->mmio_base + IOMMU_CMD_BUFFER_HEAD_OFFSET);
> + writeq(0, iommu->mmio_base + IOMMU_CMD_BUFFER_TAIL_OFFSET);
>
> iommu_set_bit(&entry, IOMMU_CONTROL_COMMAND_BUFFER_ENABLE_SHIFT);
> }
> @@ -326,8 +313,8 @@ static void set_iommu_event_log_control(
> /*reset head and tail pointer manually before enablement */
> if ( enable )
> {
> - writel(0x0, iommu->mmio_base + IOMMU_EVENT_LOG_HEAD_OFFSET);
> - writel(0x0, iommu->mmio_base + IOMMU_EVENT_LOG_TAIL_OFFSET);
> + writeq(0, iommu->mmio_base + IOMMU_EVENT_LOG_HEAD_OFFSET);
> + writeq(0, iommu->mmio_base + IOMMU_EVENT_LOG_TAIL_OFFSET);
>
> iommu_set_bit(&entry, IOMMU_CONTROL_EVENT_LOG_INT_SHIFT);
> iommu_set_bit(&entry, IOMMU_CONTROL_EVENT_LOG_ENABLE_SHIFT);
> @@ -353,8 +340,8 @@ static void set_iommu_ppr_log_control(st
> /*reset head and tail pointer manually before enablement */
> if ( enable )
> {
> - writel(0x0, iommu->mmio_base + IOMMU_PPR_LOG_HEAD_OFFSET);
> - writel(0x0, iommu->mmio_base + IOMMU_PPR_LOG_TAIL_OFFSET);
> + writeq(0, iommu->mmio_base + IOMMU_PPR_LOG_HEAD_OFFSET);
> + writeq(0, iommu->mmio_base + IOMMU_PPR_LOG_TAIL_OFFSET);
>
> iommu_set_bit(&entry, IOMMU_CONTROL_PPR_ENABLE_SHIFT);
> iommu_set_bit(&entry, IOMMU_CONTROL_PPR_INT_SHIFT);
>
>
>
next prev parent reply other threads:[~2013-06-03 9:43 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-06-03 7:12 AMD/IOMMU: revert "SR56x0 Erratum 64 - Reset all head & tail pointers" Jan Beulich
2013-06-03 9:43 ` Andrew Cooper [this message]
2013-06-04 4:41 ` Suravee Suthikulpanit
2013-06-04 6:33 ` Jan Beulich
2013-06-05 6:53 ` Suravee Suthikulpanit
2013-06-04 9:24 ` George Dunlap
2013-06-04 9:30 ` Andrew Cooper
2013-06-04 9:38 ` George Dunlap
2013-06-04 9:53 ` Ian Campbell
2013-06-04 9:56 ` George Dunlap
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