2017-08-22 10:01:07

by Anup Patel

[permalink] [raw]
Subject: [PATCH v5] FlexRM support in VFIO platform

This patchset primarily adds Broadcom FlexRM reset module for
VFIO platform driver.

The patches are based on Linux-4.13-rc3 and can also be
found at flexrm-vfio-v5 branch of
https://github.com/Broadcom/arm64-linux.git

Changes since v4:
- Use "--timeout" instead of "timeout--" in
vfio_platform_bcmflexrm_shutdown()

Changes since v3:
- Improve "depends on" for Kconfig option
VFIO_PLATFORM_BCMFLEXRM_RESET
- Fix typo in pr_warn() called by
vfio_platform_bcmflexrm_shutdown()
- Return error from vfio_platform_bcmflexrm_shutdown()
when FlexRM ring flush timeout happens

Changes since v2:
- Remove PATCH1 because fixing VFIO no-IOMMU mode is
a separate topic

Changes since v1:
- Remove iommu_present() check in vfio_iommu_group_get()
- Drop PATCH1-to-PATCH3 because IOMMU_CAP_BYPASS is not
required
- Move additional comments out of license header in
vfio_platform_bcmflexrm.c

Anup Patel (1):
vfio: platform: reset: Add Broadcom FlexRM reset module

drivers/vfio/platform/reset/Kconfig | 8 ++
drivers/vfio/platform/reset/Makefile | 1 +
.../vfio/platform/reset/vfio_platform_bcmflexrm.c | 100 +++++++++++++++++++++
3 files changed, 109 insertions(+)
create mode 100644 drivers/vfio/platform/reset/vfio_platform_bcmflexrm.c

--
2.7.4


2017-08-22 10:01:14

by Anup Patel

[permalink] [raw]
Subject: [PATCH v5] vfio: platform: reset: Add Broadcom FlexRM reset module

This patch adds Broadcom FlexRM low-level reset for
VFIO platform.

It will do the following:
1. Disable/Deactivate each FlexRM ring
2. Flush each FlexRM ring

The cleanup sequence for FlexRM rings is adapted from
Broadcom FlexRM mailbox driver.

Signed-off-by: Anup Patel <[email protected]>
Reviewed-by: Oza Oza <[email protected]>
Reviewed-by: Scott Branden <[email protected]>
Reviewed-by: Eric Auger <[email protected]>
---
drivers/vfio/platform/reset/Kconfig | 8 ++
drivers/vfio/platform/reset/Makefile | 1 +
.../vfio/platform/reset/vfio_platform_bcmflexrm.c | 100 +++++++++++++++++++++
3 files changed, 109 insertions(+)
create mode 100644 drivers/vfio/platform/reset/vfio_platform_bcmflexrm.c

diff --git a/drivers/vfio/platform/reset/Kconfig b/drivers/vfio/platform/reset/Kconfig
index 70cccc5..8833805 100644
--- a/drivers/vfio/platform/reset/Kconfig
+++ b/drivers/vfio/platform/reset/Kconfig
@@ -13,3 +13,11 @@ config VFIO_PLATFORM_AMDXGBE_RESET
Enables the VFIO platform driver to handle reset for AMD XGBE

If you don't know what to do here, say N.
+
+config VFIO_PLATFORM_BCMFLEXRM_RESET
+ tristate "VFIO support for Broadcom FlexRM reset"
+ depends on VFIO_PLATFORM && (ARCH_BCM_IPROC || COMPILE_TEST)
+ help
+ Enables the VFIO platform driver to handle reset for Broadcom FlexRM
+
+ If you don't know what to do here, say N.
diff --git a/drivers/vfio/platform/reset/Makefile b/drivers/vfio/platform/reset/Makefile
index 93f4e23..8d9874b 100644
--- a/drivers/vfio/platform/reset/Makefile
+++ b/drivers/vfio/platform/reset/Makefile
@@ -5,3 +5,4 @@ ccflags-y += -Idrivers/vfio/platform

obj-$(CONFIG_VFIO_PLATFORM_CALXEDAXGMAC_RESET) += vfio-platform-calxedaxgmac.o
obj-$(CONFIG_VFIO_PLATFORM_AMDXGBE_RESET) += vfio-platform-amdxgbe.o
+obj-$(CONFIG_VFIO_PLATFORM_BCMFLEXRM_RESET) += vfio_platform_bcmflexrm.o
diff --git a/drivers/vfio/platform/reset/vfio_platform_bcmflexrm.c b/drivers/vfio/platform/reset/vfio_platform_bcmflexrm.c
new file mode 100644
index 0000000..966a813
--- /dev/null
+++ b/drivers/vfio/platform/reset/vfio_platform_bcmflexrm.c
@@ -0,0 +1,100 @@
+/*
+ * Copyright (C) 2017 Broadcom
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/*
+ * This driver provides reset support for Broadcom FlexRM ring manager
+ * to VFIO platform.
+ */
+
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+
+#include "vfio_platform_private.h"
+
+/* FlexRM configuration */
+#define RING_REGS_SIZE 0x10000
+#define RING_VER_MAGIC 0x76303031
+
+/* Per-Ring register offsets */
+#define RING_VER 0x000
+#define RING_CONTROL 0x034
+#define RING_FLUSH_DONE 0x038
+
+/* Register RING_CONTROL fields */
+#define CONTROL_FLUSH_SHIFT 5
+
+/* Register RING_FLUSH_DONE fields */
+#define FLUSH_DONE_MASK 0x1
+
+static int vfio_platform_bcmflexrm_shutdown(void __iomem *ring)
+{
+ unsigned int timeout;
+
+ /* Disable/inactivate ring */
+ writel_relaxed(0x0, ring + RING_CONTROL);
+
+ /* Flush ring with timeout of 1s */
+ timeout = 1000;
+ writel_relaxed(BIT(CONTROL_FLUSH_SHIFT), ring + RING_CONTROL);
+ do {
+ if (readl_relaxed(ring + RING_FLUSH_DONE) & FLUSH_DONE_MASK)
+ break;
+ mdelay(1);
+ } while (--timeout);
+
+ if (!timeout) {
+ pr_warn("VFIO FlexRM shutdown timeout\n");
+ return -ETIMEDOUT;
+ }
+
+ return 0;
+}
+
+static int vfio_platform_bcmflexrm_reset(struct vfio_platform_device *vdev)
+{
+ int rc = 0;
+ void __iomem *ring;
+ struct vfio_platform_region *reg = &vdev->regions[0];
+
+ /* Map FlexRM ring registers if not mapped */
+ if (!reg->ioaddr) {
+ reg->ioaddr = ioremap_nocache(reg->addr, reg->size);
+ if (!reg->ioaddr)
+ return -ENOMEM;
+ }
+
+ /* Discover and shutdown each FlexRM ring */
+ for (ring = reg->ioaddr;
+ ring < (reg->ioaddr + reg->size); ring += RING_REGS_SIZE) {
+ if (readl_relaxed(ring + RING_VER) == RING_VER_MAGIC) {
+ rc = vfio_platform_bcmflexrm_shutdown(ring);
+ if (rc)
+ break;
+ }
+ }
+
+ return rc;
+}
+
+module_vfio_reset_handler("brcm,iproc-flexrm-mbox",
+ vfio_platform_bcmflexrm_reset);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Anup Patel <[email protected]>");
+MODULE_DESCRIPTION("Reset support for Broadcom FlexRM VFIO platform device");
--
2.7.4

2017-08-22 18:48:04

by Scott Branden

[permalink] [raw]
Subject: Re: [PATCH v5] vfio: platform: reset: Add Broadcom FlexRM reset module

Hi Anup,

We should add default (as below).


On 17-08-22 03:00 AM, Anup Patel wrote:
> This patch adds Broadcom FlexRM low-level reset for
> VFIO platform.
>
> It will do the following:
> 1. Disable/Deactivate each FlexRM ring
> 2. Flush each FlexRM ring
>
> The cleanup sequence for FlexRM rings is adapted from
> Broadcom FlexRM mailbox driver.
>
> Signed-off-by: Anup Patel <[email protected]>
> Reviewed-by: Oza Oza <[email protected]>
> Reviewed-by: Scott Branden <[email protected]>
> Reviewed-by: Eric Auger <[email protected]>
> ---
> drivers/vfio/platform/reset/Kconfig | 8 ++
> drivers/vfio/platform/reset/Makefile | 1 +
> .../vfio/platform/reset/vfio_platform_bcmflexrm.c | 100 +++++++++++++++++++++
> 3 files changed, 109 insertions(+)
> create mode 100644 drivers/vfio/platform/reset/vfio_platform_bcmflexrm.c
>
> diff --git a/drivers/vfio/platform/reset/Kconfig b/drivers/vfio/platform/reset/Kconfig
> index 70cccc5..8833805 100644
> --- a/drivers/vfio/platform/reset/Kconfig
> +++ b/drivers/vfio/platform/reset/Kconfig
> @@ -13,3 +13,11 @@ config VFIO_PLATFORM_AMDXGBE_RESET
> Enables the VFIO platform driver to handle reset for AMD XGBE
>
> If you don't know what to do here, say N.
> +
> +config VFIO_PLATFORM_BCMFLEXRM_RESET
> + tristate "VFIO support for Broadcom FlexRM reset"
> + depends on VFIO_PLATFORM && (ARCH_BCM_IPROC || COMPILE_TEST)
default ARCH_BCM_IPROC
> + help
> + Enables the VFIO platform driver to handle reset for Broadcom FlexRM
> +
> + If you don't know what to do here, say N.
>