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authorNiklas Cassel <cassel@kernel.org>2026-09-18 16:06:42 +0200
committerJens Axboe <axboe@kernel.dk>2026-09-29 12:54:47 -0600
commit684b413b5483f57c890c171b9400076a0143b918 (patch)
treef167daddad3dce9af44773541373eafbccc9ac61 /drivers/clocksource/mxs_timer.c
downloadlinux-stable-684b413b5483f57c890c171b9400076a0143b918.tar.gz
linux-stable-684b413b5483f57c890c171b9400076a0143b918.zip
virtio_blk: set the zone write granularitygrafted
virtblk_read_zoned_limits() reads the write granularity that the device reports in virtio_blk_zoned_characteristics and assigns it to the physical block size and to io_min, but never to the limit that is named after it. queue_limits.zone_write_granularity is left at zero, so blk_validate_zoned_limits() raises it to the logical block size: if (lim->zone_write_granularity < lim->logical_block_size) lim->zone_write_granularity = lim->logical_block_size; A device that reports a granularity coarser than its logical block size, which is what the field exists to express, therefore has it silently reduced. A 512e host managed disk passed through to a guest reports a logical block size of 512 and a write granularity of 4096, and the guest ends up with a zone write granularity of 512. bio_split_alignment() returns lim->zone_write_granularity if it is non-zero and bio_split_io_at() may split a bio with as per bio_split_alignment(). This can real to the write getting rejected by the host drive, as the write is not aligned to the physical block size. zonefs also takes its block size from bdev_zone_write_granularity(), so it would incorrectly use 512 on a disk that requires 4096. sd_zbc_read_zones() sets the limit from the physical block size for the same reason. NVMe ZNS and null_blk leave it unset, but the fallback gives the right answer for them, as their write granularity is the logical block size. virtio carries a separate value that may exceed it. Set the zone write granularity from the value that the device reports. Fixes: 95bfec41bd3d ("virtio-blk: add support for zoned block devices") Signed-off-by: Niklas Cassel <cassel@kernel.org> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Link: https://patch.msgid.link/20260918140641.2031075-2-cassel@kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'drivers/clocksource/mxs_timer.c')
-rw-r--r--drivers/clocksource/mxs_timer.c273
1 files changed, 273 insertions, 0 deletions
diff --git a/drivers/clocksource/mxs_timer.c b/drivers/clocksource/mxs_timer.c
new file mode 100644
index 000000000..e52e12d27
--- /dev/null
+++ b/drivers/clocksource/mxs_timer.c
@@ -0,0 +1,273 @@
+// SPDX-License-Identifier: GPL-2.0+
+//
+// Copyright (C) 2000-2001 Deep Blue Solutions
+// Copyright (C) 2002 Shane Nay (shane@minirl.com)
+// Copyright (C) 2006-2007 Pavel Pisa (ppisa@pikron.com)
+// Copyright (C) 2008 Juergen Beisert (kernel@pengutronix.de)
+// Copyright (C) 2010 Freescale Semiconductor, Inc. All Rights Reserved.
+
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/clockchips.h>
+#include <linux/clk.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/stmp_device.h>
+#include <linux/sched_clock.h>
+
+/*
+ * There are 2 versions of the timrot on Freescale MXS-based SoCs.
+ * The v1 on MX23 only gets 16 bits counter, while v2 on MX28
+ * extends the counter to 32 bits.
+ *
+ * The implementation uses two timers, one for clock_event and
+ * another for clocksource. MX28 uses timrot 0 and 1, while MX23
+ * uses 0 and 2.
+ */
+
+#define MX23_TIMROT_VERSION_OFFSET 0x0a0
+#define MX28_TIMROT_VERSION_OFFSET 0x120
+#define BP_TIMROT_MAJOR_VERSION 24
+#define BV_TIMROT_VERSION_1 0x01
+#define BV_TIMROT_VERSION_2 0x02
+#define timrot_is_v1() (timrot_major_version == BV_TIMROT_VERSION_1)
+
+/*
+ * There are 4 registers for each timrotv2 instance, and 2 registers
+ * for each timrotv1. So address step 0x40 in macros below strides
+ * one instance of timrotv2 while two instances of timrotv1.
+ *
+ * As the result, HW_TIMROT_XXXn(1) defines the address of timrot1
+ * on MX28 while timrot2 on MX23.
+ */
+/* common between v1 and v2 */
+#define HW_TIMROT_ROTCTRL 0x00
+#define HW_TIMROT_TIMCTRLn(n) (0x20 + (n) * 0x40)
+/* v1 only */
+#define HW_TIMROT_TIMCOUNTn(n) (0x30 + (n) * 0x40)
+/* v2 only */
+#define HW_TIMROT_RUNNING_COUNTn(n) (0x30 + (n) * 0x40)
+#define HW_TIMROT_FIXED_COUNTn(n) (0x40 + (n) * 0x40)
+
+#define BM_TIMROT_TIMCTRLn_RELOAD (1 << 6)
+#define BM_TIMROT_TIMCTRLn_UPDATE (1 << 7)
+#define BM_TIMROT_TIMCTRLn_IRQ_EN (1 << 14)
+#define BM_TIMROT_TIMCTRLn_IRQ (1 << 15)
+#define BP_TIMROT_TIMCTRLn_SELECT 0
+#define BV_TIMROTv1_TIMCTRLn_SELECT__32KHZ_XTAL 0x8
+#define BV_TIMROTv2_TIMCTRLn_SELECT__32KHZ_XTAL 0xb
+#define BV_TIMROTv2_TIMCTRLn_SELECT__TICK_ALWAYS 0xf
+
+static struct clock_event_device mxs_clockevent_device;
+
+static void __iomem *mxs_timrot_base;
+static u32 timrot_major_version;
+
+static inline void timrot_irq_disable(void)
+{
+ __raw_writel(BM_TIMROT_TIMCTRLn_IRQ_EN, mxs_timrot_base +
+ HW_TIMROT_TIMCTRLn(0) + STMP_OFFSET_REG_CLR);
+}
+
+static inline void timrot_irq_enable(void)
+{
+ __raw_writel(BM_TIMROT_TIMCTRLn_IRQ_EN, mxs_timrot_base +
+ HW_TIMROT_TIMCTRLn(0) + STMP_OFFSET_REG_SET);
+}
+
+static void timrot_irq_acknowledge(void)
+{
+ __raw_writel(BM_TIMROT_TIMCTRLn_IRQ, mxs_timrot_base +
+ HW_TIMROT_TIMCTRLn(0) + STMP_OFFSET_REG_CLR);
+}
+
+static u64 timrotv1_get_cycles(struct clocksource *cs)
+{
+ return ~((__raw_readl(mxs_timrot_base + HW_TIMROT_TIMCOUNTn(1))
+ & 0xffff0000) >> 16);
+}
+
+static int timrotv1_set_next_event(unsigned long evt,
+ struct clock_event_device *dev)
+{
+ /* timrot decrements the count */
+ __raw_writel(evt, mxs_timrot_base + HW_TIMROT_TIMCOUNTn(0));
+
+ return 0;
+}
+
+static int timrotv2_set_next_event(unsigned long evt,
+ struct clock_event_device *dev)
+{
+ /* timrot decrements the count */
+ __raw_writel(evt, mxs_timrot_base + HW_TIMROT_FIXED_COUNTn(0));
+
+ return 0;
+}
+
+static irqreturn_t mxs_timer_interrupt(int irq, void *dev_id)
+{
+ struct clock_event_device *evt = dev_id;
+
+ timrot_irq_acknowledge();
+ evt->event_handler(evt);
+
+ return IRQ_HANDLED;
+}
+
+static void mxs_irq_clear(char *state)
+{
+ /* Disable interrupt in timer module */
+ timrot_irq_disable();
+
+ /* Set event time into the furthest future */
+ if (timrot_is_v1())
+ __raw_writel(0xffff, mxs_timrot_base + HW_TIMROT_TIMCOUNTn(1));
+ else
+ __raw_writel(0xffffffff,
+ mxs_timrot_base + HW_TIMROT_FIXED_COUNTn(1));
+
+ /* Clear pending interrupt */
+ timrot_irq_acknowledge();
+ pr_debug("%s: changing mode to %s\n", __func__, state);
+}
+
+static int mxs_shutdown(struct clock_event_device *evt)
+{
+ mxs_irq_clear("shutdown");
+
+ return 0;
+}
+
+static int mxs_set_oneshot(struct clock_event_device *evt)
+{
+ if (clockevent_state_oneshot(evt))
+ mxs_irq_clear("oneshot");
+ timrot_irq_enable();
+ return 0;
+}
+
+static struct clock_event_device mxs_clockevent_device = {
+ .name = "mxs_timrot",
+ .features = CLOCK_EVT_FEAT_ONESHOT,
+ .set_state_shutdown = mxs_shutdown,
+ .set_state_oneshot = mxs_set_oneshot,
+ .tick_resume = mxs_shutdown,
+ .set_next_event = timrotv2_set_next_event,
+ .rating = 200,
+};
+
+static int __init mxs_clockevent_init(struct clk *timer_clk)
+{
+ if (timrot_is_v1())
+ mxs_clockevent_device.set_next_event = timrotv1_set_next_event;
+ mxs_clockevent_device.cpumask = cpumask_of(0);
+ clockevents_config_and_register(&mxs_clockevent_device,
+ clk_get_rate(timer_clk),
+ timrot_is_v1() ? 0xf : 0x2,
+ timrot_is_v1() ? 0xfffe : 0xfffffffe);
+
+ return 0;
+}
+
+static struct clocksource clocksource_mxs = {
+ .name = "mxs_timer",
+ .rating = 200,
+ .read = timrotv1_get_cycles,
+ .mask = CLOCKSOURCE_MASK(16),
+ .flags = CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
+static u64 notrace mxs_read_sched_clock_v2(void)
+{
+ return ~readl_relaxed(mxs_timrot_base + HW_TIMROT_RUNNING_COUNTn(1));
+}
+
+static int __init mxs_clocksource_init(struct clk *timer_clk)
+{
+ unsigned int c = clk_get_rate(timer_clk);
+
+ if (timrot_is_v1())
+ clocksource_register_hz(&clocksource_mxs, c);
+ else {
+ clocksource_mmio_init(mxs_timrot_base + HW_TIMROT_RUNNING_COUNTn(1),
+ "mxs_timer", c, 200, 32, clocksource_mmio_readl_down);
+ sched_clock_register(mxs_read_sched_clock_v2, 32, c);
+ }
+
+ return 0;
+}
+
+static int __init mxs_timer_init(struct device_node *np)
+{
+ struct clk *timer_clk;
+ int irq, ret;
+
+ mxs_timrot_base = of_iomap(np, 0);
+ WARN_ON(!mxs_timrot_base);
+
+ timer_clk = of_clk_get(np, 0);
+ if (IS_ERR(timer_clk)) {
+ pr_err("%s: failed to get clk\n", __func__);
+ return PTR_ERR(timer_clk);
+ }
+
+ ret = clk_prepare_enable(timer_clk);
+ if (ret)
+ return ret;
+
+ /*
+ * Initialize timers to a known state
+ */
+ stmp_reset_block(mxs_timrot_base + HW_TIMROT_ROTCTRL);
+
+ /* get timrot version */
+ timrot_major_version = __raw_readl(mxs_timrot_base +
+ (of_device_is_compatible(np, "fsl,imx23-timrot") ?
+ MX23_TIMROT_VERSION_OFFSET :
+ MX28_TIMROT_VERSION_OFFSET));
+ timrot_major_version >>= BP_TIMROT_MAJOR_VERSION;
+
+ /* one for clock_event */
+ __raw_writel((timrot_is_v1() ?
+ BV_TIMROTv1_TIMCTRLn_SELECT__32KHZ_XTAL :
+ BV_TIMROTv2_TIMCTRLn_SELECT__TICK_ALWAYS) |
+ BM_TIMROT_TIMCTRLn_UPDATE |
+ BM_TIMROT_TIMCTRLn_IRQ_EN,
+ mxs_timrot_base + HW_TIMROT_TIMCTRLn(0));
+
+ /* another for clocksource */
+ __raw_writel((timrot_is_v1() ?
+ BV_TIMROTv1_TIMCTRLn_SELECT__32KHZ_XTAL :
+ BV_TIMROTv2_TIMCTRLn_SELECT__TICK_ALWAYS) |
+ BM_TIMROT_TIMCTRLn_RELOAD,
+ mxs_timrot_base + HW_TIMROT_TIMCTRLn(1));
+
+ /* set clocksource timer fixed count to the maximum */
+ if (timrot_is_v1())
+ __raw_writel(0xffff,
+ mxs_timrot_base + HW_TIMROT_TIMCOUNTn(1));
+ else
+ __raw_writel(0xffffffff,
+ mxs_timrot_base + HW_TIMROT_FIXED_COUNTn(1));
+
+ /* init and register the timer to the framework */
+ ret = mxs_clocksource_init(timer_clk);
+ if (ret)
+ return ret;
+
+ ret = mxs_clockevent_init(timer_clk);
+ if (ret)
+ return ret;
+
+ /* Make irqs happen */
+ irq = irq_of_parse_and_map(np, 0);
+ if (irq <= 0)
+ return -EINVAL;
+
+ return request_irq(irq, mxs_timer_interrupt, IRQF_TIMER | IRQF_IRQPOLL,
+ "MXS Timer Tick", &mxs_clockevent_device);
+}
+TIMER_OF_DECLARE(mxs, "fsl,timrot", mxs_timer_init);