[PATCH AUTOSEL 5.15 1/9] leds: trigger: panic: Don't register panic notifier if creating the trigger failed

[PATCH AUTOSEL 5.15 1/9] leds: trigger: panic: Don't register panic notifier if creating the trigger failed

[Sasha Levin]

From: Heiner Kallweit <hkallweit1@gmail.com>

[ Upstream commit afacb21834bb02785ddb0c3ec197208803b74faa ]

It doesn't make sense to register the panic notifier if creating the
panic trigger failed.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Link: https://lore.kernel.org/r/8a61e229-5388-46c7-919a-4d18cc7362b2@gmail.com
Signed-off-by: Lee Jones <lee@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/leds/trigger/ledtrig-panic.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/leds/trigger/ledtrig-panic.c b/drivers/leds/trigger/ledtrig-panic.c
index 64abf2e91608..5a6b21bfeb9a 100644
--- a/drivers/leds/trigger/ledtrig-panic.c
+++ b/drivers/leds/trigger/ledtrig-panic.c
@@ -64,10 +64,13 @@ static long led_panic_blink(int state)
 
 static int __init ledtrig_panic_init(void)
 {
+	led_trigger_register_simple("panic", &trigger);
+	if (!trigger)
+		return -ENOMEM;
+
 	atomic_notifier_chain_register(&panic_notifier_list,
 				       &led_trigger_panic_nb);
 
-	led_trigger_register_simple("panic", &trigger);
 	panic_blink = led_panic_blink;
 	return 0;
 }
-- 
2.43.0

[PATCH AUTOSEL 5.15 2/9] um: Fix naming clash between UML and scheduler

[Sasha Levin]

From: Anton Ivanov <anton.ivanov@cambridgegreys.com>

[ Upstream commit 541d4e4d435c8b9bfd29f70a1da4a2db97794e0a ]

__cant_sleep was already used and exported by the scheduler.
The name had to be changed to a UML specific one.

Signed-off-by: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Reviewed-by: Peter Lafreniere <peter@n8pjl.ca>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/um/include/shared/kern_util.h | 2 +-
 arch/um/kernel/process.c           | 2 +-
 arch/um/os-Linux/helper.c          | 6 +++---
 3 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/arch/um/include/shared/kern_util.h b/arch/um/include/shared/kern_util.h
index a2cfd42608a0..cb798a50e8cf 100644
--- a/arch/um/include/shared/kern_util.h
+++ b/arch/um/include/shared/kern_util.h
@@ -50,7 +50,7 @@ extern void do_uml_exitcalls(void);
  * Are we disallowed to sleep? Used to choose between GFP_KERNEL and
  * GFP_ATOMIC.
  */
-extern int __cant_sleep(void);
+extern int __uml_cant_sleep(void);
 extern int get_current_pid(void);
 extern int copy_from_user_proc(void *to, void *from, int size);
 extern int cpu(void);
diff --git a/arch/um/kernel/process.c b/arch/um/kernel/process.c
index b3fbfca49400..4b6179a8a3e8 100644
--- a/arch/um/kernel/process.c
+++ b/arch/um/kernel/process.c
@@ -218,7 +218,7 @@ void arch_cpu_idle(void)
 	raw_local_irq_enable();
 }
 
-int __cant_sleep(void) {
+int __uml_cant_sleep(void) {
 	return in_atomic() || irqs_disabled() || in_interrupt();
 	/* Is in_interrupt() really needed? */
 }
diff --git a/arch/um/os-Linux/helper.c b/arch/um/os-Linux/helper.c
index 32e88baf18dd..4e429a41565c 100644
--- a/arch/um/os-Linux/helper.c
+++ b/arch/um/os-Linux/helper.c
@@ -45,7 +45,7 @@ int run_helper(void (*pre_exec)(void *), void *pre_data, char **argv)
 	unsigned long stack, sp;
 	int pid, fds[2], ret, n;
 
-	stack = alloc_stack(0, __cant_sleep());
+	stack = alloc_stack(0, __uml_cant_sleep());
 	if (stack == 0)
 		return -ENOMEM;
 
@@ -69,7 +69,7 @@ int run_helper(void (*pre_exec)(void *), void *pre_data, char **argv)
 	data.pre_data = pre_data;
 	data.argv = argv;
 	data.fd = fds[1];
-	data.buf = __cant_sleep() ? uml_kmalloc(PATH_MAX, UM_GFP_ATOMIC) :
+	data.buf = __uml_cant_sleep() ? uml_kmalloc(PATH_MAX, UM_GFP_ATOMIC) :
 					uml_kmalloc(PATH_MAX, UM_GFP_KERNEL);
 	pid = clone(helper_child, (void *) sp, CLONE_VM, &data);
 	if (pid < 0) {
@@ -116,7 +116,7 @@ int run_helper_thread(int (*proc)(void *), void *arg, unsigned int flags,
 	unsigned long stack, sp;
 	int pid, status, err;
 
-	stack = alloc_stack(0, __cant_sleep());
+	stack = alloc_stack(0, __uml_cant_sleep());
 	if (stack == 0)
 		return -ENOMEM;
 
-- 
2.43.0

[PATCH AUTOSEL 5.15 3/9] um: Don't use vfprintf() for os_info()

[Sasha Levin]

From: Benjamin Berg <benjamin@sipsolutions.net>

[ Upstream commit 236f9fe39b02c15fa5530b53e9cca48354394389 ]

The threads allocated inside the kernel have only a single page of
stack. Unfortunately, the vfprintf function in standard glibc may use
too much stack-space, overflowing it.

To make os_info safe to be used by helper threads, use the kernel
vscnprintf function into a smallish buffer and write out the information
to stderr.

Signed-off-by: Benjamin Berg <benjamin@sipsolutions.net>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/um/os-Linux/util.c | 19 +++++++++++++++++--
 1 file changed, 17 insertions(+), 2 deletions(-)

diff --git a/arch/um/os-Linux/util.c b/arch/um/os-Linux/util.c
index fc0f2a9dee5a..1dca4ffbd572 100644
--- a/arch/um/os-Linux/util.c
+++ b/arch/um/os-Linux/util.c
@@ -173,23 +173,38 @@ __uml_setup("quiet", quiet_cmd_param,
 "quiet\n"
 "    Turns off information messages during boot.\n\n");
 
+/*
+ * The os_info/os_warn functions will be called by helper threads. These
+ * have a very limited stack size and using the libc formatting functions
+ * may overflow the stack.
+ * So pull in the kernel vscnprintf and use that instead with a fixed
+ * on-stack buffer.
+ */
+int vscnprintf(char *buf, size_t size, const char *fmt, va_list args);
+
 void os_info(const char *fmt, ...)
 {
+	char buf[256];
 	va_list list;
+	int len;
 
 	if (quiet_info)
 		return;
 
 	va_start(list, fmt);
-	vfprintf(stderr, fmt, list);
+	len = vscnprintf(buf, sizeof(buf), fmt, list);
+	fwrite(buf, len, 1, stderr);
 	va_end(list);
 }
 
 void os_warn(const char *fmt, ...)
 {
+	char buf[256];
 	va_list list;
+	int len;
 
 	va_start(list, fmt);
-	vfprintf(stderr, fmt, list);
+	len = vscnprintf(buf, sizeof(buf), fmt, list);
+	fwrite(buf, len, 1, stderr);
 	va_end(list);
 }
-- 
2.43.0

[PATCH AUTOSEL 5.15 4/9] um: net: Fix return type of uml_net_start_xmit()

[Sasha Levin]

From: Nathan Chancellor <nathan@kernel.org>

[ Upstream commit 7d748f60a4b82b50bf25fad1bd42d33f049f76aa ]

With clang's kernel control flow integrity (kCFI, CONFIG_CFI_CLANG),
indirect call targets are validated against the expected function
pointer prototype to make sure the call target is valid to help mitigate
ROP attacks. If they are not identical, there is a failure at run time,
which manifests as either a kernel panic or thread getting killed. A
warning in clang aims to catch these at compile time, which reveals:

  arch/um/drivers/net_kern.c:353:21: warning: incompatible function pointer types initializing 'netdev_tx_t (*)(struct sk_buff *, struct net_device *)' (aka 'enum netdev_tx (*)(struct sk_buff *, struct net_device *)') with an expression of type 'int (struct sk_buff *, struct net_device *)' [-Wincompatible-function-pointer-types-strict]
    353 |         .ndo_start_xmit         = uml_net_start_xmit,
        |                                   ^~~~~~~~~~~~~~~~~~
  1 warning generated.

->ndo_start_xmit() in 'struct net_device_ops' expects a return type of
'netdev_tx_t', not 'int'. Adjust the return type of uml_net_start_xmit()
to match the prototype's to resolve the warning. While UML does not
currently implement support for kCFI, it could in the future, which
means this warning becomes a fatal CFI failure at run time.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202310031340.v1vPh207-lkp@intel.com/
Acked-by: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/um/drivers/net_kern.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/um/drivers/net_kern.c b/arch/um/drivers/net_kern.c
index 2fc0b038ff8a..e24bc9aaff4a 100644
--- a/arch/um/drivers/net_kern.c
+++ b/arch/um/drivers/net_kern.c
@@ -204,7 +204,7 @@ static int uml_net_close(struct net_device *dev)
 	return 0;
 }
 
-static int uml_net_start_xmit(struct sk_buff *skb, struct net_device *dev)
+static netdev_tx_t uml_net_start_xmit(struct sk_buff *skb, struct net_device *dev)
 {
 	struct uml_net_private *lp = netdev_priv(dev);
 	unsigned long flags;
-- 
2.43.0

[PATCH AUTOSEL 5.15 5/9] um: time-travel: fix time corruption

[Sasha Levin]

From: Johannes Berg <johannes.berg@intel.com>

[ Upstream commit abe4eaa8618bb36c2b33e9cdde0499296a23448c ]

In 'basic' time-travel mode (without =inf-cpu or =ext), we
still get timer interrupts. These can happen at arbitrary
points in time, i.e. while in timer_read(), which pushes
time forward just a little bit. Then, if we happen to get
the interrupt after calculating the new time to push to,
but before actually finishing that, the interrupt will set
the time to a value that's incompatible with the forward,
and we'll crash because time goes backwards when we do the
forwarding.

Fix this by reading the time_travel_time, calculating the
adjustment, and doing the adjustment all with interrupts
disabled.

Reported-by: Vincent Whitchurch <Vincent.Whitchurch@axis.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/um/kernel/time.c | 32 +++++++++++++++++++++++++++-----
 1 file changed, 27 insertions(+), 5 deletions(-)

diff --git a/arch/um/kernel/time.c b/arch/um/kernel/time.c
index fddd1dec27e6..3e270da6b6f6 100644
--- a/arch/um/kernel/time.c
+++ b/arch/um/kernel/time.c
@@ -432,9 +432,29 @@ static void time_travel_update_time(unsigned long long next, bool idle)
 	time_travel_del_event(&ne);
 }
 
+static void time_travel_update_time_rel(unsigned long long offs)
+{
+	unsigned long flags;
+
+	/*
+	 * Disable interrupts before calculating the new time so
+	 * that a real timer interrupt (signal) can't happen at
+	 * a bad time e.g. after we read time_travel_time but
+	 * before we've completed updating the time.
+	 */
+	local_irq_save(flags);
+	time_travel_update_time(time_travel_time + offs, false);
+	local_irq_restore(flags);
+}
+
 void time_travel_ndelay(unsigned long nsec)
 {
-	time_travel_update_time(time_travel_time + nsec, false);
+	/*
+	 * Not strictly needed to use _rel() version since this is
+	 * only used in INFCPU/EXT modes, but it doesn't hurt and
+	 * is more readable too.
+	 */
+	time_travel_update_time_rel(nsec);
 }
 EXPORT_SYMBOL(time_travel_ndelay);
 
@@ -568,7 +588,11 @@ static void time_travel_set_start(void)
 #define time_travel_time 0
 #define time_travel_ext_waiting 0
 
-static inline void time_travel_update_time(unsigned long long ns, bool retearly)
+static inline void time_travel_update_time(unsigned long long ns, bool idle)
+{
+}
+
+static inline void time_travel_update_time_rel(unsigned long long offs)
 {
 }
 
@@ -720,9 +744,7 @@ static u64 timer_read(struct clocksource *cs)
 		 */
 		if (!irqs_disabled() && !in_interrupt() && !in_softirq() &&
 		    !time_travel_ext_waiting)
-			time_travel_update_time(time_travel_time +
-						TIMER_MULTIPLIER,
-						false);
+			time_travel_update_time_rel(TIMER_MULTIPLIER);
 		return time_travel_time / TIMER_MULTIPLIER;
 	}
 
-- 
2.43.0

[PATCH AUTOSEL 5.15 6/9] i3c: master: cdns: Update maximum prescaler value for i2c clock

[Sasha Levin]

From: Harshit Shah <harshitshah.opendev@gmail.com>

[ Upstream commit 374c13f9080a1b9835a5ed3e7bea93cf8e2dc262 ]

As per the Cadence IP document fixed the I2C clock divider value limit from
16 bits instead of 10 bits. Without this change setting up the I2C clock to
low frequencies will not work as the prescaler value might be greater than
10 bit number.

I3C clock divider value is 10 bits only. Updating the macro names for both.

Signed-off-by: Harshit Shah <harshitshah.opendev@gmail.com>
Link: https://lore.kernel.org/r/1703927483-28682-1-git-send-email-harshitshah.opendev@gmail.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/i3c/master/i3c-master-cdns.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/i3c/master/i3c-master-cdns.c b/drivers/i3c/master/i3c-master-cdns.c
index 4a49c75a9408..b9cfda6ae9ae 100644
--- a/drivers/i3c/master/i3c-master-cdns.c
+++ b/drivers/i3c/master/i3c-master-cdns.c
@@ -77,7 +77,8 @@
 #define PRESCL_CTRL0			0x14
 #define PRESCL_CTRL0_I2C(x)		((x) << 16)
 #define PRESCL_CTRL0_I3C(x)		(x)
-#define PRESCL_CTRL0_MAX		GENMASK(9, 0)
+#define PRESCL_CTRL0_I3C_MAX		GENMASK(9, 0)
+#define PRESCL_CTRL0_I2C_MAX		GENMASK(15, 0)
 
 #define PRESCL_CTRL1			0x18
 #define PRESCL_CTRL1_PP_LOW_MASK	GENMASK(15, 8)
@@ -1234,7 +1235,7 @@ static int cdns_i3c_master_bus_init(struct i3c_master_controller *m)
 		return -EINVAL;
 
 	pres = DIV_ROUND_UP(sysclk_rate, (bus->scl_rate.i3c * 4)) - 1;
-	if (pres > PRESCL_CTRL0_MAX)
+	if (pres > PRESCL_CTRL0_I3C_MAX)
 		return -ERANGE;
 
 	bus->scl_rate.i3c = sysclk_rate / ((pres + 1) * 4);
@@ -1247,7 +1248,7 @@ static int cdns_i3c_master_bus_init(struct i3c_master_controller *m)
 	max_i2cfreq = bus->scl_rate.i2c;
 
 	pres = (sysclk_rate / (max_i2cfreq * 5)) - 1;
-	if (pres > PRESCL_CTRL0_MAX)
+	if (pres > PRESCL_CTRL0_I2C_MAX)
 		return -ERANGE;
 
 	bus->scl_rate.i2c = sysclk_rate / ((pres + 1) * 5);
-- 
2.43.0

[PATCH AUTOSEL 5.15 7/9] xen/gntdev: Fix the abuse of underlying struct page in DMA-buf import

[Sasha Levin]

From: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>

[ Upstream commit 2d2db7d40254d5fb53b11ebd703cd1ed0c5de7a1 ]

DO NOT access the underlying struct page of an sg table exported
by DMA-buf in dmabuf_imp_to_refs(), this is not allowed.
Please see drivers/dma-buf/dma-buf.c:mangle_sg_table() for details.

Fortunately, here (for special Xen device) we can avoid using
pages and calculate gfns directly from dma addresses provided by
the sg table.

Suggested-by: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Acked-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Acked-by: Daniel Vetter <daniel@ffwll.ch>
Link: https://lore.kernel.org/r/20240107103426.2038075-1-olekstysh@gmail.com
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/xen/gntdev-dmabuf.c | 50 ++++++++++++++++++-------------------
 1 file changed, 25 insertions(+), 25 deletions(-)

diff --git a/drivers/xen/gntdev-dmabuf.c b/drivers/xen/gntdev-dmabuf.c
index 4c13cbc99896..398ea69c176c 100644
--- a/drivers/xen/gntdev-dmabuf.c
+++ b/drivers/xen/gntdev-dmabuf.c
@@ -11,6 +11,7 @@
 #include <linux/kernel.h>
 #include <linux/errno.h>
 #include <linux/dma-buf.h>
+#include <linux/dma-direct.h>
 #include <linux/slab.h>
 #include <linux/types.h>
 #include <linux/uaccess.h>
@@ -56,7 +57,7 @@ struct gntdev_dmabuf {
 
 	/* Number of pages this buffer has. */
 	int nr_pages;
-	/* Pages of this buffer. */
+	/* Pages of this buffer (only for dma-buf export). */
 	struct page **pages;
 };
 
@@ -490,7 +491,7 @@ static int dmabuf_exp_from_refs(struct gntdev_priv *priv, int flags,
 /* DMA buffer import support. */
 
 static int
-dmabuf_imp_grant_foreign_access(struct page **pages, u32 *refs,
+dmabuf_imp_grant_foreign_access(unsigned long *gfns, u32 *refs,
 				int count, int domid)
 {
 	grant_ref_t priv_gref_head;
@@ -513,7 +514,7 @@ dmabuf_imp_grant_foreign_access(struct page **pages, u32 *refs,
 		}
 
 		gnttab_grant_foreign_access_ref(cur_ref, domid,
-						xen_page_to_gfn(pages[i]), 0);
+						gfns[i], 0);
 		refs[i] = cur_ref;
 	}
 
@@ -535,7 +536,6 @@ static void dmabuf_imp_end_foreign_access(u32 *refs, int count)
 
 static void dmabuf_imp_free_storage(struct gntdev_dmabuf *gntdev_dmabuf)
 {
-	kfree(gntdev_dmabuf->pages);
 	kfree(gntdev_dmabuf->u.imp.refs);
 	kfree(gntdev_dmabuf);
 }
@@ -555,12 +555,6 @@ static struct gntdev_dmabuf *dmabuf_imp_alloc_storage(int count)
 	if (!gntdev_dmabuf->u.imp.refs)
 		goto fail;
 
-	gntdev_dmabuf->pages = kcalloc(count,
-				       sizeof(gntdev_dmabuf->pages[0]),
-				       GFP_KERNEL);
-	if (!gntdev_dmabuf->pages)
-		goto fail;
-
 	gntdev_dmabuf->nr_pages = count;
 
 	for (i = 0; i < count; i++)
@@ -582,7 +576,8 @@ dmabuf_imp_to_refs(struct gntdev_dmabuf_priv *priv, struct device *dev,
 	struct dma_buf *dma_buf;
 	struct dma_buf_attachment *attach;
 	struct sg_table *sgt;
-	struct sg_page_iter sg_iter;
+	struct sg_dma_page_iter sg_iter;
+	unsigned long *gfns;
 	int i;
 
 	dma_buf = dma_buf_get(fd);
@@ -630,26 +625,31 @@ dmabuf_imp_to_refs(struct gntdev_dmabuf_priv *priv, struct device *dev,
 
 	gntdev_dmabuf->u.imp.sgt = sgt;
 
-	/* Now convert sgt to array of pages and check for page validity. */
+	gfns = kcalloc(count, sizeof(*gfns), GFP_KERNEL);
+	if (!gfns) {
+		ret = ERR_PTR(-ENOMEM);
+		goto fail_unmap;
+	}
+
+	/*
+	 * Now convert sgt to array of gfns without accessing underlying pages.
+	 * It is not allowed to access the underlying struct page of an sg table
+	 * exported by DMA-buf, but since we deal with special Xen dma device here
+	 * (not a normal physical one) look at the dma addresses in the sg table
+	 * and then calculate gfns directly from them.
+	 */
 	i = 0;
-	for_each_sgtable_page(sgt, &sg_iter, 0) {
-		struct page *page = sg_page_iter_page(&sg_iter);
-		/*
-		 * Check if page is valid: this can happen if we are given
-		 * a page from VRAM or other resources which are not backed
-		 * by a struct page.
-		 */
-		if (!pfn_valid(page_to_pfn(page))) {
-			ret = ERR_PTR(-EINVAL);
-			goto fail_unmap;
-		}
+	for_each_sgtable_dma_page(sgt, &sg_iter, 0) {
+		dma_addr_t addr = sg_page_iter_dma_address(&sg_iter);
+		unsigned long pfn = bfn_to_pfn(XEN_PFN_DOWN(dma_to_phys(dev, addr)));
 
-		gntdev_dmabuf->pages[i++] = page;
+		gfns[i++] = pfn_to_gfn(pfn);
 	}
 
-	ret = ERR_PTR(dmabuf_imp_grant_foreign_access(gntdev_dmabuf->pages,
+	ret = ERR_PTR(dmabuf_imp_grant_foreign_access(gfns,
 						      gntdev_dmabuf->u.imp.refs,
 						      count, domid));
+	kfree(gfns);
 	if (IS_ERR(ret))
 		goto fail_end_access;
 
-- 
2.43.0

[PATCH AUTOSEL 5.15 8/9] mfd: ti_am335x_tscadc: Fix TI SoC dependencies

[Sasha Levin]

From: Peter Robinson <pbrobinson@gmail.com>

[ Upstream commit 284d16c456e5d4b143f375b8ccc4038ab3f4ee0f ]

The ti_am335x_tscadc is specific to some TI SoCs, update
the dependencies for those SoCs and compile testing.

Signed-off-by: Peter Robinson <pbrobinson@gmail.com>
Link: https://lore.kernel.org/r/20231220155643.445849-1-pbrobinson@gmail.com
Signed-off-by: Lee Jones <lee@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/mfd/Kconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index ef550d33af92..1a790e7f6549 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -1377,6 +1377,7 @@ config MFD_DAVINCI_VOICECODEC
 
 config MFD_TI_AM335X_TSCADC
 	tristate "TI ADC / Touch Screen chip support"
+	depends on ARCH_OMAP2PLUS || ARCH_K3 || COMPILE_TEST
 	select MFD_CORE
 	select REGMAP
 	select REGMAP_MMIO
-- 
2.43.0

[PATCH AUTOSEL 5.15 9/9] mailbox: arm_mhuv2: Fix a bug for mhuv2_sender_interrupt

[Sasha Levin]

From: "Xiaowu.ding" <xiaowu.ding@jaguarmicro.com>

[ Upstream commit ee01c0b4384d19ecc5dfa7db3fd4303f965c3eba ]

Message Handling Unit version is v2.1.

When arm_mhuv2 working with the data protocol transfer mode.
We have split one mhu into two channels, and every channel
include four channel windows, the two channels share
one gic spi interrupt.

There is a problem with the sending scenario.

The first channel will take up 0-3 channel windows, and the second
channel take up 4-7 channel windows. When the first channel send the
data, and the receiver will clear all the four channels status.
Although we only enabled the interrupt on the last channel window with
register CH_INT_EN,the register CHCOMB_INT_ST0 will be 0xf, not be 0x8.
Currently we just clear the last channel windows int status with the
data proctol mode.So after that,the CHCOMB_INT_ST0 status will be 0x7,
not be the 0x0.

Then the second channel send the data, the receiver read the
data, clear all the four channel windows status, trigger the sender
interrupt. But currently the CHCOMB_INT_ST0 register will be 0xf7,
get_irq_chan_comb function will always return the first channel.

So this patch clear all channel windows int status to avoid this interrupt
confusion.

Signed-off-by: Xiaowu.ding <xiaowu.ding@jaguarmicro.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/mailbox/arm_mhuv2.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/mailbox/arm_mhuv2.c b/drivers/mailbox/arm_mhuv2.c
index 3af15083a25a..68f766621b9b 100644
--- a/drivers/mailbox/arm_mhuv2.c
+++ b/drivers/mailbox/arm_mhuv2.c
@@ -552,7 +552,8 @@ static irqreturn_t mhuv2_sender_interrupt(int irq, void *data)
 	priv = chan->con_priv;
 
 	if (!IS_PROTOCOL_DOORBELL(priv)) {
-		writel_relaxed(1, &mhu->send->ch_wn[priv->ch_wn_idx + priv->windows - 1].int_clr);
+		for (i = 0; i < priv->windows; i++)
+			writel_relaxed(1, &mhu->send->ch_wn[priv->ch_wn_idx + i].int_clr);
 
 		if (chan->cl) {
 			mbox_chan_txdone(chan, 0);
-- 
2.43.0