Linux-ACPI Archive on lore.kernel.org
 help / color / Atom feed
From: Mika Westerberg <mika.westerberg@linux.intel.com>
To: linux-kernel@vger.kernel.org
Cc: Andreas Noever <andreas.noever@gmail.com>,
	Michael Jamet <michael.jamet@intel.com>,
	Yehezkel Bernat <YehezkelShB@gmail.com>,
	"Rafael J. Wysocki" <rjw@rjwysocki.net>,
	Len Brown <lenb@kernel.org>, Lukas Wunner <lukas@wunner.de>,
	Mario.Limonciello@dell.com,
	Anthony Wong <anthony.wong@canonical.com>,
	Rajmohan Mani <rajmohan.mani@intel.com>,
	Raanan Avargil <raanan.avargil@intel.com>,
	David Laight <David.Laight@ACULAB.COM>,
	Mika Westerberg <mika.westerberg@linux.intel.com>,
	linux-acpi@vger.kernel.org
Subject: [PATCH v3 3/8] thunderbolt: Use 32-bit writes when writing ring producer/consumer
Date: Mon, 19 Aug 2019 14:22:18 +0300
Message-ID: <20190819112223.15359-4-mika.westerberg@linux.intel.com> (raw)
In-Reply-To: <20190819112223.15359-1-mika.westerberg@linux.intel.com>

The register access should be using 32-bit reads/writes according to the
datasheet. With the previous generation hardware 16-bit writes have been
working but starting with ICL this is not the case anymore so fix
producer/consumer register update to use correct width register address.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Yehezkel Bernat <YehezkelShB@gmail.com>
---
 drivers/thunderbolt/nhi.c | 22 ++++++++++++++++++----
 1 file changed, 18 insertions(+), 4 deletions(-)

diff --git a/drivers/thunderbolt/nhi.c b/drivers/thunderbolt/nhi.c
index 27fbe62c7ddd..9c782706e652 100644
--- a/drivers/thunderbolt/nhi.c
+++ b/drivers/thunderbolt/nhi.c
@@ -143,9 +143,20 @@ static void __iomem *ring_options_base(struct tb_ring *ring)
 	return io;
 }
 
-static void ring_iowrite16desc(struct tb_ring *ring, u32 value, u32 offset)
+static void ring_iowrite_cons(struct tb_ring *ring, u16 cons)
 {
-	iowrite16(value, ring_desc_base(ring) + offset);
+	/*
+	 * The other 16-bits in the register is read-only and writes to it
+	 * are ignored by the hardware so we can save one ioread32() by
+	 * filling the read-only bits with zeroes.
+	 */
+	iowrite32(cons, ring_desc_base(ring) + 8);
+}
+
+static void ring_iowrite_prod(struct tb_ring *ring, u16 prod)
+{
+	/* See ring_iowrite_cons() above for explanation */
+	iowrite32(prod << 16, ring_desc_base(ring) + 8);
 }
 
 static void ring_iowrite32desc(struct tb_ring *ring, u32 value, u32 offset)
@@ -197,7 +208,10 @@ static void ring_write_descriptors(struct tb_ring *ring)
 			descriptor->sof = frame->sof;
 		}
 		ring->head = (ring->head + 1) % ring->size;
-		ring_iowrite16desc(ring, ring->head, ring->is_tx ? 10 : 8);
+		if (ring->is_tx)
+			ring_iowrite_prod(ring, ring->head);
+		else
+			ring_iowrite_cons(ring, ring->head);
 	}
 }
 
@@ -662,7 +676,7 @@ void tb_ring_stop(struct tb_ring *ring)
 
 	ring_iowrite32options(ring, 0, 0);
 	ring_iowrite64desc(ring, 0, 0);
-	ring_iowrite16desc(ring, 0, ring->is_tx ? 10 : 8);
+	ring_iowrite32desc(ring, 0, 8);
 	ring_iowrite32desc(ring, 0, 12);
 	ring->head = 0;
 	ring->tail = 0;
-- 
2.23.0.rc1


  parent reply index

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-08-19 11:22 [PATCH v3 0/8] thunderbolt: Intel Ice Lake support Mika Westerberg
2019-08-19 11:22 ` [PATCH v3 1/8] thunderbolt: Correct path indices for PCIe tunnel Mika Westerberg
2019-08-19 11:22 ` [PATCH v3 2/8] thunderbolt: Move NVM upgrade support flag to struct icm Mika Westerberg
2019-08-19 11:22 ` Mika Westerberg [this message]
2019-08-19 11:22 ` [PATCH v3 4/8] thunderbolt: Do not fail adding switch if some port is not implemented Mika Westerberg
2019-08-19 11:22 ` [PATCH v3 5/8] thunderbolt: Hide switch attributes that are not set Mika Westerberg
2019-08-19 11:22 ` [PATCH v3 6/8] thunderbolt: Expose active parts of NVM even if upgrade is not supported Mika Westerberg
2019-08-19 11:22 ` [PATCH v3 7/8] thunderbolt: Add support for Intel Ice Lake Mika Westerberg
2019-08-19 11:22 ` [PATCH v3 8/8] ACPI / property: Add two new Thunderbolt property GUIDs to the list Mika Westerberg
2019-08-19 16:29 ` [PATCH v3 0/8] thunderbolt: Intel Ice Lake support Mario.Limonciello
2019-08-19 17:57   ` Mika Westerberg
2019-08-19 18:22     ` Mario.Limonciello
2019-08-19 19:36       ` Mario.Limonciello
2019-08-20 10:01         ` Mika Westerberg
2019-08-20 11:34   ` Lukas Wunner
2019-08-20 17:00     ` Mario.Limonciello
2019-08-26  9:20 ` Mika Westerberg

Reply instructions:

You may reply publically to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20190819112223.15359-4-mika.westerberg@linux.intel.com \
    --to=mika.westerberg@linux.intel.com \
    --cc=David.Laight@ACULAB.COM \
    --cc=Mario.Limonciello@dell.com \
    --cc=YehezkelShB@gmail.com \
    --cc=andreas.noever@gmail.com \
    --cc=anthony.wong@canonical.com \
    --cc=lenb@kernel.org \
    --cc=linux-acpi@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=lukas@wunner.de \
    --cc=michael.jamet@intel.com \
    --cc=raanan.avargil@intel.com \
    --cc=rajmohan.mani@intel.com \
    --cc=rjw@rjwysocki.net \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

Linux-ACPI Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-acpi/0 linux-acpi/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-acpi linux-acpi/ https://lore.kernel.org/linux-acpi \
		linux-acpi@vger.kernel.org linux-acpi@archiver.kernel.org
	public-inbox-index linux-acpi

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-acpi


AGPL code for this site: git clone https://public-inbox.org/ public-inbox