diff mbox series

[12/13] mailbox: pcc: Add support for PCCT extended PCC subspaces(type 3/4)

Message ID 20210708180851.2311192-13-sudeep.holla@arm.com (mailing list archive)
State Not Applicable, archived
Headers show
Series mailbox: pcc: Add support for PCCT extended PCC subspaces | expand

Commit Message

Sudeep Holla July 8, 2021, 6:08 p.m. UTC 
With all the plumbing in place to avoid accessing PCCT type and other
fields directly from the PCCT table all the time, let us now add the
support for extended PCC subspaces(type 3 and 4).

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
---
 drivers/mailbox/pcc.c | 119 ++++++++++++++++++++++++++++++++++++------
 1 file changed, 102 insertions(+), 17 deletions(-)

Comments

Cristian Marussi July 14, 2021, 6:52 p.m. UTC | #1 
On Thu, Jul 08, 2021 at 07:08:50PM +0100, Sudeep Holla wrote:
> With all the plumbing in place to avoid accessing PCCT type and other
> fields directly from the PCCT table all the time, let us now add the
> support for extended PCC subspaces(type 3 and 4).
> 
> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
> ---

Hi Sudeep,

just a few general observation on Type 3/4 subspaces from the spec
Table 14.7:

- "If a slave-subspace is present in the PCCT, then the platform interrupt flag must be set to 1." table 14.7

  Maybe is worth to WARN on this if this assumption is violated by the
  ACPI table we found.

- "Note that if interrupts are edge triggered, then each subspace must have its own unique interrupt."

  Same here, maybe it's worth also to check this, so that after all the
  pchan->db_irq has been obtained no edge triggered irqs are duplicated
  before requesting them.

Thanks,
Cristian
Sudeep Holla July 15, 2021, 11:31 a.m. UTC | #2 
On Wed, Jul 14, 2021 at 07:52:16PM +0100, Cristian Marussi wrote:
> On Thu, Jul 08, 2021 at 07:08:50PM +0100, Sudeep Holla wrote:
> > With all the plumbing in place to avoid accessing PCCT type and other
> > fields directly from the PCCT table all the time, let us now add the
> > support for extended PCC subspaces(type 3 and 4).
> >
> > Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
> > ---
>
> Hi Sudeep,
>
> just a few general observation on Type 3/4 subspaces from the spec
> Table 14.7:
>
> - "If a slave-subspace is present in the PCCT, then the platform interrupt flag must be set to 1." table 14.7
>
>   Maybe is worth to WARN on this if this assumption is violated by the
>   ACPI table we found.
>
> - "Note that if interrupts are edge triggered, then each subspace must have its own unique interrupt."
>
>   Same here, maybe it's worth also to check this, so that after all the
>   pchan->db_irq has been obtained no edge triggered irqs are duplicated
>   before requesting them.
>

Both valid points and in my TODO list, just forgot to address this as I
didn't have a setup to check/flag these up. I will address them in next
version.

Thanks for reviewing these patches.

--
Regards,
Sudeep
diff mbox series

Patch

diff --git a/drivers/mailbox/pcc.c b/drivers/mailbox/pcc.c
index 99ad3429f174..22d1c7691887 100644
--- a/drivers/mailbox/pcc.c
+++ b/drivers/mailbox/pcc.c
@@ -89,12 +89,18 @@  struct pcc_chan_reg {
  * @db: PCC register bundle for the doorbell register
  * @plat_irq_ack: PCC register bundle for the platform interrupt acknowledge
  *	register
+ * @cmd_complete: PCC register bundle for the command complete check register
+ * @cmd_update: PCC register bundle for the command complete update register
+ * @error: PCC register bundle for the error status register
  * @db_irq: doorbell interrupt
  */
 struct pcc_chan_info {
 	struct pcc_mbox_chan chan;
 	struct pcc_chan_reg db;
 	struct pcc_chan_reg plat_irq_ack;
+	struct pcc_chan_reg cmd_complete;
+	struct pcc_chan_reg cmd_update;
+	struct pcc_chan_reg error;
 	int db_irq;
 };
 
@@ -228,9 +234,29 @@  static irqreturn_t pcc_mbox_irq(int irq, void *p)
 {
 	struct pcc_chan_info *pchan;
 	struct mbox_chan *chan = p;
+	u64 val;
+	int ret;
 
 	pchan = chan->con_priv;
 
+	ret = pcc_chan_reg_read(&pchan->cmd_complete, &val);
+	if (ret)
+		return IRQ_NONE;
+
+	val &= pchan->cmd_complete.status_mask;
+	if (!val)
+		return IRQ_NONE;
+
+	ret = pcc_chan_reg_read(&pchan->error, &val);
+	if (ret)
+		return IRQ_NONE;
+	val &= pchan->error.status_mask;
+	if (val) {
+		val &= ~pchan->error.status_mask;
+		pcc_chan_reg_write(&pchan->error, val);
+		return IRQ_NONE;
+	}
+
 	mbox_chan_received_data(chan, NULL);
 
 	if (pcc_chan_reg_read_modify_write(&pchan->plat_irq_ack))
@@ -335,8 +361,13 @@  EXPORT_SYMBOL_GPL(pcc_mbox_free_channel);
  */
 static int pcc_send_data(struct mbox_chan *chan, void *data)
 {
+	int ret;
 	struct pcc_chan_info *pchan = chan->con_priv;
 
+	ret = pcc_chan_reg_read_modify_write(&pchan->cmd_update);
+	if (ret)
+		return ret;
+
 	return pcc_chan_reg_read_modify_write(&pchan->db);
 }
 
@@ -429,6 +460,16 @@  static int pcc_parse_subspace_irq(struct pcc_chan_info *pchan,
 					pcct2_ss->ack_preserve_mask,
 					pcct2_ss->ack_write_mask, 0,
 					"PLAT IRQ ACK");
+
+	} else if (pcct_ss->header.type == ACPI_PCCT_TYPE_EXT_PCC_MASTER_SUBSPACE ||
+		   pcct_ss->header.type == ACPI_PCCT_TYPE_EXT_PCC_SLAVE_SUBSPACE) {
+		struct acpi_pcct_ext_pcc_master *pcct_ext = (void *)pcct_ss;
+
+		ret = pcc_chan_reg_init(&pchan->plat_irq_ack,
+					&pcct_ext->platform_ack_register,
+					pcct_ext->ack_preserve_mask,
+					pcct_ext->ack_set_mask, 0,
+					"PLAT IRQ ACK");
 	}
 
 	return ret;
@@ -446,14 +487,48 @@  static int pcc_parse_subspace_db_reg(struct pcc_chan_info *pchan,
 {
 	int ret = 0;
 
-	struct acpi_pcct_subspace *pcct_ss;
-
-	pcct_ss = (struct acpi_pcct_subspace *)pcct_entry;
-
-	ret = pcc_chan_reg_init(&pchan->db,
-				&pcct_ss->doorbell_register,
-				pcct_ss->preserve_mask,
-				pcct_ss->write_mask, 0,	"Doorbell");
+	if (pcct_entry->type <= ACPI_PCCT_TYPE_HW_REDUCED_SUBSPACE_TYPE2) {
+		struct acpi_pcct_subspace *pcct_ss;
+
+		pcct_ss = (struct acpi_pcct_subspace *)pcct_entry;
+
+		ret = pcc_chan_reg_init(&pchan->db,
+					&pcct_ss->doorbell_register,
+					pcct_ss->preserve_mask,
+					pcct_ss->write_mask, 0,	"Doorbell");
+
+	} else {
+		struct acpi_pcct_ext_pcc_master *pcct_ext;
+
+		pcct_ext = (struct acpi_pcct_ext_pcc_master *)pcct_entry;
+
+		ret = pcc_chan_reg_init(&pchan->db,
+					&pcct_ext->doorbell_register,
+					pcct_ext->preserve_mask,
+					pcct_ext->write_mask, 0, "Doorbell");
+		if (ret)
+			return ret;
+
+		ret = pcc_chan_reg_init(&pchan->cmd_complete,
+					&pcct_ext->cmd_complete_register,
+					0, 0, pcct_ext->cmd_complete_mask,
+					"Command Complete Check");
+		if (ret)
+			return ret;
+
+		ret = pcc_chan_reg_init(&pchan->cmd_update,
+					&pcct_ext->cmd_update_register,
+					pcct_ext->cmd_update_preserve_mask,
+					pcct_ext->cmd_update_set_mask, 0,
+					"Command Complete Update");
+		if (ret)
+			return ret;
+
+		ret = pcc_chan_reg_init(&pchan->error,
+					&pcct_ext->error_status_register,
+					0, 0, pcct_ext->error_status_mask,
+					"Error Status");
+	}
 	return ret;
 }
 
@@ -467,15 +542,25 @@  static int pcc_parse_subspace_db_reg(struct pcc_chan_info *pchan,
 static void pcc_parse_subspace_shmem(struct pcc_chan_info *pchan,
 				     struct acpi_subtable_header *pcct_entry)
 {
-	struct acpi_pcct_subspace *pcct_ss;
-
-	pcct_ss = (struct acpi_pcct_subspace *)pcct_entry;
-
-	pchan->chan.shmem_base_addr = pcct_ss->base_address;
-	pchan->chan.shmem_size = pcct_ss->length;
-	pchan->chan.latency = pcct_ss->latency;
-	pchan->chan.max_access_rate = pcct_ss->max_access_rate;
-	pchan->chan.min_turnaround_time = pcct_ss->min_turnaround_time;
+	if (pcct_entry->type <= ACPI_PCCT_TYPE_HW_REDUCED_SUBSPACE_TYPE2) {
+		struct acpi_pcct_subspace *pcct_ss =
+			(struct acpi_pcct_subspace *)pcct_entry;
+
+		pchan->chan.shmem_base_addr = pcct_ss->base_address;
+		pchan->chan.shmem_size = pcct_ss->length;
+		pchan->chan.latency = pcct_ss->latency;
+		pchan->chan.max_access_rate = pcct_ss->max_access_rate;
+		pchan->chan.min_turnaround_time = pcct_ss->min_turnaround_time;
+	} else {
+		struct acpi_pcct_ext_pcc_master *pcct_ext =
+			(struct acpi_pcct_ext_pcc_master *)pcct_entry;
+
+		pchan->chan.shmem_base_addr = pcct_ext->base_address;
+		pchan->chan.shmem_size = pcct_ext->length;
+		pchan->chan.latency = pcct_ext->latency;
+		pchan->chan.max_access_rate = pcct_ext->max_access_rate;
+		pchan->chan.min_turnaround_time = pcct_ext->min_turnaround_time;
+	}
 }
 
 /**