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[PATCH v6 7/9] iommu/amd: Move erratum 63 logic to write_dte_lower128()

Suravee Suthikulpanit posted 9 patches 1 month, 1 week ago
There is a newer version of this series
[PATCH v6 7/9] iommu/amd: Move erratum 63 logic to write_dte_lower128()
Posted by Suravee Suthikulpanit 1 month, 1 week ago 
To simplify DTE programming, and remove amd_iommu_apply_erratum_63() and
helper functions since no longer used.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
---
 drivers/iommu/amd/amd_iommu.h       |  1 -
 drivers/iommu/amd/amd_iommu_types.h |  2 ++
 drivers/iommu/amd/init.c            | 36 -----------------------------
 drivers/iommu/amd/iommu.c           |  6 +++--
 4 files changed, 6 insertions(+), 39 deletions(-)

diff --git a/drivers/iommu/amd/amd_iommu.h b/drivers/iommu/amd/amd_iommu.h
index 96c3bfc234f8..1467bfc34fdf 100644
--- a/drivers/iommu/amd/amd_iommu.h
+++ b/drivers/iommu/amd/amd_iommu.h
@@ -16,7 +16,6 @@ irqreturn_t amd_iommu_int_thread_evtlog(int irq, void *data);
 irqreturn_t amd_iommu_int_thread_pprlog(int irq, void *data);
 irqreturn_t amd_iommu_int_thread_galog(int irq, void *data);
 irqreturn_t amd_iommu_int_handler(int irq, void *data);
-void amd_iommu_apply_erratum_63(struct amd_iommu *iommu, u16 devid);
 void amd_iommu_restart_log(struct amd_iommu *iommu, const char *evt_type,
 			   u8 cntrl_intr, u8 cntrl_log,
 			   u32 status_run_mask, u32 status_overflow_mask);
diff --git a/drivers/iommu/amd/amd_iommu_types.h b/drivers/iommu/amd/amd_iommu_types.h
index 3f53d3bc79cb..53e129835b26 100644
--- a/drivers/iommu/amd/amd_iommu_types.h
+++ b/drivers/iommu/amd/amd_iommu_types.h
@@ -220,6 +220,8 @@
 #define DEV_ENTRY_EX            0x67
 #define DEV_ENTRY_SYSMGT1       0x68
 #define DEV_ENTRY_SYSMGT2       0x69
+#define DTE_DATA1_SYSMGT_MASK	GENMASK_ULL(41, 40)
+
 #define DEV_ENTRY_IRQ_TBL_EN	0x80
 #define DEV_ENTRY_INIT_PASS     0xb8
 #define DEV_ENTRY_EINT_PASS     0xb9
diff --git a/drivers/iommu/amd/init.c b/drivers/iommu/amd/init.c
index 552a13f7668c..31f10a071abd 100644
--- a/drivers/iommu/amd/init.c
+++ b/drivers/iommu/amd/init.c
@@ -1014,29 +1014,6 @@ static void __set_dev_entry_bit(struct dev_table_entry *dev_table,
 	dev_table[devid].data[i] |= (1UL << _bit);
 }
 
-static void set_dev_entry_bit(struct amd_iommu *iommu, u16 devid, u8 bit)
-{
-	struct dev_table_entry *dev_table = get_dev_table(iommu);
-
-	return __set_dev_entry_bit(dev_table, devid, bit);
-}
-
-static int __get_dev_entry_bit(struct dev_table_entry *dev_table,
-			       u16 devid, u8 bit)
-{
-	int i = (bit >> 6) & 0x03;
-	int _bit = bit & 0x3f;
-
-	return (dev_table[devid].data[i] & (1UL << _bit)) >> _bit;
-}
-
-static int get_dev_entry_bit(struct amd_iommu *iommu, u16 devid, u8 bit)
-{
-	struct dev_table_entry *dev_table = get_dev_table(iommu);
-
-	return __get_dev_entry_bit(dev_table, devid, bit);
-}
-
 static bool __copy_device_table(struct amd_iommu *iommu)
 {
 	u64 int_ctl, int_tab_len, entry = 0;
@@ -1152,17 +1129,6 @@ static bool copy_device_table(void)
 	return true;
 }
 
-void amd_iommu_apply_erratum_63(struct amd_iommu *iommu, u16 devid)
-{
-	int sysmgt;
-
-	sysmgt = get_dev_entry_bit(iommu, devid, DEV_ENTRY_SYSMGT1) |
-		 (get_dev_entry_bit(iommu, devid, DEV_ENTRY_SYSMGT2) << 1);
-
-	if (sysmgt == 0x01)
-		set_dev_entry_bit(iommu, devid, DEV_ENTRY_IW);
-}
-
 /*
  * This function takes the device specific flags read from the ACPI
  * table and sets up the device table entry with that information
@@ -1185,8 +1151,6 @@ static void __init set_dev_entry_from_acpi(struct amd_iommu *iommu,
 	if (flags & ACPI_DEVFLAG_LINT1)
 		set_dte_cache_bit(iommu, devid, DEV_ENTRY_LINT1_PASS);
 
-	amd_iommu_apply_erratum_63(iommu, devid);
-
 	amd_iommu_set_rlookup_table(iommu, devid);
 }
 
diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
index c03e2d9d2990..a8c0a57003a8 100644
--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c
@@ -105,6 +105,10 @@ static void write_dte_lower128(struct dev_table_entry *ptr, struct dev_table_ent
 
 	old.data128[0] = READ_ONCE(ptr->data128[0]);
 	do {
+		/* Apply erratum 63 */
+		if (FIELD_GET(DTE_DATA1_SYSMGT_MASK, new->data[1]) == 0x1)
+			new->data[0] |= DTE_FLAG_IW;
+
 	/* Note: try_cmpxchg inherently update &old.data128[0] on failure */
 	} while (!try_cmpxchg128(&ptr->data128[0], &old.data128[0], new->data128[0]));
 }
@@ -2117,8 +2121,6 @@ static void clear_dte_entry(struct amd_iommu *iommu, u16 devid)
 		dev_table[devid].data[0] |= DTE_FLAG_TV;
 
 	dev_table[devid].data[1] &= DTE_FLAG_MASK;
-
-	amd_iommu_apply_erratum_63(iommu, devid);
 }
 
 /* Update and flush DTE for the given device */
-- 
2.34.1
Re: [PATCH v6 7/9] iommu/amd: Move erratum 63 logic to write_dte_lower128()
Posted by Jason Gunthorpe 1 month, 1 week ago 
On Wed, Oct 16, 2024 at 05:17:54AM +0000, Suravee Suthikulpanit wrote:

> diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
> index c03e2d9d2990..a8c0a57003a8 100644
> --- a/drivers/iommu/amd/iommu.c
> +++ b/drivers/iommu/amd/iommu.c
> @@ -105,6 +105,10 @@ static void write_dte_lower128(struct dev_table_entry *ptr, struct dev_table_ent
>  
>  	old.data128[0] = READ_ONCE(ptr->data128[0]);
>  	do {
> +		/* Apply erratum 63 */
> +		if (FIELD_GET(DTE_DATA1_SYSMGT_MASK, new->data[1]) == 0x1)
> +			new->data[0] |= DTE_FLAG_IW;
> +

Why not put it in set_dte_entry() ?

Jason
Re: [PATCH v6 7/9] iommu/amd: Move erratum 63 logic to write_dte_lower128()
Posted by Suthikulpanit, Suravee 3 weeks, 5 days ago 

On 10/16/2024 8:30 PM, Jason Gunthorpe wrote:
> On Wed, Oct 16, 2024 at 05:17:54AM +0000, Suravee Suthikulpanit wrote:
> 
>> diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
>> index c03e2d9d2990..a8c0a57003a8 100644
>> --- a/drivers/iommu/amd/iommu.c
>> +++ b/drivers/iommu/amd/iommu.c
>> @@ -105,6 +105,10 @@ static void write_dte_lower128(struct dev_table_entry *ptr, struct dev_table_ent
>>   
>>   	old.data128[0] = READ_ONCE(ptr->data128[0]);
>>   	do {
>> +		/* Apply erratum 63 */
>> +		if (FIELD_GET(DTE_DATA1_SYSMGT_MASK, new->data[1]) == 0x1)
>> +			new->data[0] |= DTE_FLAG_IW;
>> +
> 
> Why not put it in set_dte_entry() ?

Ok. Good point.

Suravee
Re: [PATCH v6 7/9] iommu/amd: Move erratum 63 logic to write_dte_lower128()
Posted by Suthikulpanit, Suravee 3 weeks, 5 days ago 

On 10/16/2024 8:30 PM, Jason Gunthorpe wrote:
> On Wed, Oct 16, 2024 at 05:17:54AM +0000, Suravee Suthikulpanit wrote:
> 
>> diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
>> index c03e2d9d2990..a8c0a57003a8 100644
>> --- a/drivers/iommu/amd/iommu.c
>> +++ b/drivers/iommu/amd/iommu.c
>> @@ -105,6 +105,10 @@ static void write_dte_lower128(struct dev_table_entry *ptr, struct dev_table_ent
>>   
>>   	old.data128[0] = READ_ONCE(ptr->data128[0]);
>>   	do {
>> +		/* Apply erratum 63 */
>> +		if (FIELD_GET(DTE_DATA1_SYSMGT_MASK, new->data[1]) == 0x1)
>> +			new->data[0] |= DTE_FLAG_IW;
>> +
> 
> Why not put it in set_dte_entry() ?
> 
> Jason

I have reworked this part in v7 to move it to other part. I will send 
out v7 for review next.

Suravee

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