[RFC 0/1] ITS fails to allocate on rk3588

[RFC 0/1] ITS fails to allocate on rk3588

[Lucas Tanure]

I am assisting with PCIe and networking bring-up for Rock Pi 5B (RK3588).
This chip uses the same GICv3 as RK356X but has fixed the previous
limitation of GIC only supporting 32-bit addresses.

But the implementation decision for shareability in GICR and GITS is
still the same.

I read the previous thread about this topic:
https://lore.kernel.org/lkml/2791594e-db60-e1d0-88e5-7e5bbd98ae4d@rock-chips.com/T/#m5dbc70ff308d81e98dd0d797e23d3fbf9c353245

From my understanding, the errata numbers Marc Zyngier is referring to
are found in Arm errata documents at developer.arm.com/documentation.
But I could not find Cavium or Broadcom pages for errata with those
numbers in Documentation/arm64/silicon-errata.rst

I could not find an errata document about this shareability issue,
and by what Kever said in the previous thread this could be a
RockChip design decision.

Marc, as I could only find ARM errata numbers, is the errata number
you were expecting generated by ARM only, or RockChip should issue
a document like Arm to detail the issue?

Can this shareability issue be seen as a quirk without an
errata number?

The following patch is based on the work of Peter Geis for the
Quartz64 board and the previous thread feedback.

Lucas Tanure (1):
  irqchip/gic-v3: Add RK3588 GICR and GITS no share workaround

 Documentation/arm64/silicon-errata.rst |  4 +++
 arch/arm64/Kconfig                     | 13 ++++++++
 drivers/irqchip/irq-gic-v3-its.c       | 42 ++++++++++++++++++++++++++
 3 files changed, 59 insertions(+)

-- 
2.39.2


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[RFC 1/1] irqchip/gic-v3: Add RK3588 GICR and GITS no share workaround

[Lucas Tanure]

The GIC600 integration in RK356x, used in rk3588, doesn't support
any of the shareability or cacheability attributes, and requires
both values to be set to 0b00 for all the ITS and Redistributor
tables.

Based on work of Peter Geis for the Quartz64 board.

Signed-off-by: Lucas Tanure <lucas.tanure@collabora.com>
---
 Documentation/arm64/silicon-errata.rst |  4 +++
 arch/arm64/Kconfig                     | 13 ++++++++
 drivers/irqchip/irq-gic-v3-its.c       | 42 ++++++++++++++++++++++++++
 3 files changed, 59 insertions(+)

diff --git a/Documentation/arm64/silicon-errata.rst b/Documentation/arm64/silicon-errata.rst
index ec5f889d7681..b26cf8ca7d5c 100644
--- a/Documentation/arm64/silicon-errata.rst
+++ b/Documentation/arm64/silicon-errata.rst
@@ -209,3 +209,7 @@ stable kernels.
 +----------------+-----------------+-----------------+-----------------------------+
 | Fujitsu        | A64FX           | E#010001        | FUJITSU_ERRATUM_010001      |
 +----------------+-----------------+-----------------+-----------------------------+
+
++----------------+-----------------+-----------------+-----------------------------+
+| RockChip       | RK3588          | N/A             | ROCKCHIP_NO_SHARE           |
++----------------+-----------------+-----------------+-----------------------------+
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 27b2592698b0..ad3f1742052b 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -1150,6 +1150,19 @@ config NVIDIA_CARMEL_CNP_ERRATUM
 
 	  If unsure, say Y.
 
+config ROCKCHIP_NO_SHARE
+	bool "Rockchip RK3588 GIC6000 No shareability or cacheability attributes"
+	default y
+	help
+	  The GIC600 integration in RK356x doesn't support any of the shareability or
+	  cacheability attributes, and requires both values to be set to 0b00 for all 
+	  the ITS and Redistributor tables.
+
+	  Work around the issue by clearing the GICR_PROPBASER_SHAREABILITY_MASK from
+	  register reads at GICR and GITS.
+
+	  If unsure, say Y.
+
 config SOCIONEXT_SYNQUACER_PREITS
 	bool "Socionext Synquacer: Workaround for GICv3 pre-ITS"
 	default y
diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index 586271b8aa39..637e2e2a1ab1 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -42,6 +42,7 @@
 #define ITS_FLAGS_CMDQ_NEEDS_FLUSHING		(1ULL << 0)
 #define ITS_FLAGS_WORKAROUND_CAVIUM_22375	(1ULL << 1)
 #define ITS_FLAGS_WORKAROUND_CAVIUM_23144	(1ULL << 2)
+#define ITS_FLAGS_WORKAROUND_ROCKCHIP_NOSHARE	(1ULL << 3)
 
 #define RDIST_FLAGS_PROPBASE_NEEDS_FLUSHING	(1 << 0)
 #define RDIST_FLAGS_RD_TABLES_PREALLOCATED	(1 << 1)
@@ -2359,6 +2360,15 @@ static int its_setup_baser(struct its_node *its, struct its_baser *baser,
 	its_write_baser(its, baser, val);
 	tmp = baser->val;
 
+#if CONFIG_ROCKCHIP_NO_SHARE
+	if (its->flags & ITS_FLAGS_WORKAROUND_ROCKCHIP_NOSHARE) {
+		if (tmp & GITS_BASER_SHAREABILITY_MASK)
+			tmp &= ~GITS_BASER_SHAREABILITY_MASK;
+		else
+			gic_flush_dcache_to_poc(base, PAGE_ORDER_TO_SIZE(order));
+	}
+#endif
+
 	if ((val ^ tmp) & GITS_BASER_SHAREABILITY_MASK) {
 		/*
 		 * Shareability didn't stick. Just use
@@ -3057,6 +3067,7 @@ static void its_cpu_init_lpis(void)
 {
 	void __iomem *rbase = gic_data_rdist_rd_base();
 	struct page *pend_page;
+	struct its_node *its;
 	phys_addr_t paddr;
 	u64 val, tmp;
 
@@ -3096,6 +3107,12 @@ static void its_cpu_init_lpis(void)
 	gicr_write_propbaser(val, rbase + GICR_PROPBASER);
 	tmp = gicr_read_propbaser(rbase + GICR_PROPBASER);
 
+#if CONFIG_ROCKCHIP_NO_SHARE
+	its = list_first_entry(&its_nodes, struct its_node, entry);
+	if (its->flags & ITS_FLAGS_WORKAROUND_ROCKCHIP_NOSHARE)
+		tmp &= ~GICR_PROPBASER_SHAREABILITY_MASK;
+#endif
+
 	if ((tmp ^ val) & GICR_PROPBASER_SHAREABILITY_MASK) {
 		if (!(tmp & GICR_PROPBASER_SHAREABILITY_MASK)) {
 			/*
@@ -3120,6 +3137,11 @@ static void its_cpu_init_lpis(void)
 	gicr_write_pendbaser(val, rbase + GICR_PENDBASER);
 	tmp = gicr_read_pendbaser(rbase + GICR_PENDBASER);
 
+#if CONFIG_ROCKCHIP_NO_SHARE
+	if (its->flags & ITS_FLAGS_WORKAROUND_ROCKCHIP_NOSHARE)
+		tmp &= ~GICR_PENDBASER_SHAREABILITY_MASK;
+#endif
+
 	if (!(tmp & GICR_PENDBASER_SHAREABILITY_MASK)) {
 		/*
 		 * The HW reports non-shareable, we must remove the
@@ -4710,6 +4732,14 @@ static bool __maybe_unused its_enable_quirk_hip07_161600802(void *data)
 	return true;
 }
 
+static bool __maybe_unused its_enable_quirk_rk356x(void *data)
+{
+	struct its_node *its = data;
+
+	its->flags |= ITS_FLAGS_WORKAROUND_ROCKCHIP_NOSHARE;
+	return true;
+}
+
 static const struct gic_quirk its_quirks[] = {
 #ifdef CONFIG_CAVIUM_ERRATUM_22375
 	{
@@ -4755,6 +4785,14 @@ static const struct gic_quirk its_quirks[] = {
 		.mask	= 0xffffffff,
 		.init	= its_enable_quirk_hip07_161600802,
 	},
+#endif
+#ifdef CONFIG_ROCKCHIP_NO_SHARE
+	{
+		.desc	= "ITS: Rockchip RK356X/RK3588 doesn't support shareability",
+		.iidr	= 0x0201743b,
+		.mask	= 0xffffffff,
+		.init	= its_enable_quirk_rk356x,
+	},
 #endif
 	{
 	}
@@ -5096,6 +5134,10 @@ static int __init its_probe_one(struct resource *res,
 	gits_write_cbaser(baser, its->base + GITS_CBASER);
 	tmp = gits_read_cbaser(its->base + GITS_CBASER);
 
+#if CONFIG_ROCKCHIP_NO_SHARE
+	if (its->flags & ITS_FLAGS_WORKAROUND_ROCKCHIP_NOSHARE)
+		tmp &= ~GITS_CBASER_SHAREABILITY_MASK;
+#endif
 	if ((tmp ^ baser) & GITS_CBASER_SHAREABILITY_MASK) {
 		if (!(tmp & GITS_CBASER_SHAREABILITY_MASK)) {
 			/*
-- 
2.39.2


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Re: [RFC 1/1] irqchip/gic-v3: Add RK3588 GICR and GITS no share workaround

[AngeloGioacchino Del Regno]

Il 27/02/23 16:18, Lucas Tanure ha scritto:
> The GIC600 integration in RK356x, used in rk3588, doesn't support
> any of the shareability or cacheability attributes, and requires
> both values to be set to 0b00 for all the ITS and Redistributor
> tables.
> 
> Based on work of Peter Geis for the Quartz64 board.
> 
> Signed-off-by: Lucas Tanure <lucas.tanure@collabora.com>
> ---
>   Documentation/arm64/silicon-errata.rst |  4 +++
>   arch/arm64/Kconfig                     | 13 ++++++++
>   drivers/irqchip/irq-gic-v3-its.c       | 42 ++++++++++++++++++++++++++
>   3 files changed, 59 insertions(+)
> 
> diff --git a/Documentation/arm64/silicon-errata.rst b/Documentation/arm64/silicon-errata.rst
> index ec5f889d7681..b26cf8ca7d5c 100644
> --- a/Documentation/arm64/silicon-errata.rst
> +++ b/Documentation/arm64/silicon-errata.rst
> @@ -209,3 +209,7 @@ stable kernels.
>   +----------------+-----------------+-----------------+-----------------------------+
>   | Fujitsu        | A64FX           | E#010001        | FUJITSU_ERRATUM_010001      |
>   +----------------+-----------------+-----------------+-----------------------------+
> +
> ++----------------+-----------------+-----------------+-----------------------------+
> +| RockChip       | RK3588          | N/A             | ROCKCHIP_NO_SHARE           |
> ++----------------+-----------------+-----------------+-----------------------------+

This should go after Qualcomm, as it looks like this file is ordered by name but
for some reason Fujitsu got at the bottom.
Just keep your new addition ordered.

Besides, I propose the following:

| RockChip       | RK3588          | N/A             | ROCKCHIP_ITS_ERRATUM       |

> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
> index 27b2592698b0..ad3f1742052b 100644
> --- a/arch/arm64/Kconfig
> +++ b/arch/arm64/Kconfig
> @@ -1150,6 +1150,19 @@ config NVIDIA_CARMEL_CNP_ERRATUM
>   
>   	  If unsure, say Y.
>   
> +config ROCKCHIP_NO_SHARE

config ROCKCHIP_ITS_ERRATUM ?? :-)

> +	bool "Rockchip RK3588 GIC6000 No shareability or cacheability attributes"

You've got a typo here: GIC6000.

> +	default y
> +	help
> +	  The GIC600 integration in RK356x doesn't support any of the shareability or
> +	  cacheability attributes, and requires both values to be set to 0b00 for all
> +	  the ITS and Redistributor tables.
> +
> +	  Work around the issue by clearing the GICR_PROPBASER_SHAREABILITY_MASK from
> +	  register reads at GICR and GITS.
> +
> +	  If unsure, say Y.
> +
>   config SOCIONEXT_SYNQUACER_PREITS
>   	bool "Socionext Synquacer: Workaround for GICv3 pre-ITS"
>   	default y
> diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
> index 586271b8aa39..637e2e2a1ab1 100644
> --- a/drivers/irqchip/irq-gic-v3-its.c
> +++ b/drivers/irqchip/irq-gic-v3-its.c
> @@ -42,6 +42,7 @@
>   #define ITS_FLAGS_CMDQ_NEEDS_FLUSHING		(1ULL << 0)
>   #define ITS_FLAGS_WORKAROUND_CAVIUM_22375	(1ULL << 1)
>   #define ITS_FLAGS_WORKAROUND_CAVIUM_23144	(1ULL << 2)
> +#define ITS_FLAGS_WORKAROUND_ROCKCHIP_NOSHARE	(1ULL << 3)
>   
>   #define RDIST_FLAGS_PROPBASE_NEEDS_FLUSHING	(1 << 0)
>   #define RDIST_FLAGS_RD_TABLES_PREALLOCATED	(1 << 1)
> @@ -2359,6 +2360,15 @@ static int its_setup_baser(struct its_node *its, struct its_baser *baser,
>   	its_write_baser(its, baser, val);
>   	tmp = baser->val;
>   
> +#if CONFIG_ROCKCHIP_NO_SHARE

None of the other workarounds have an ifdef in parsing the flags, so I think
that you can avoid enclosing this in a preprocessor `if` block.

> +	if (its->flags & ITS_FLAGS_WORKAROUND_ROCKCHIP_NOSHARE) {
> +		if (tmp & GITS_BASER_SHAREABILITY_MASK)
> +			tmp &= ~GITS_BASER_SHAREABILITY_MASK;
> +		else
> +			gic_flush_dcache_to_poc(base, PAGE_ORDER_TO_SIZE(order));
> +	}
> +#endif
> +
>   	if ((val ^ tmp) & GITS_BASER_SHAREABILITY_MASK) {
>   		/*
>   		 * Shareability didn't stick. Just use
> @@ -3057,6 +3067,7 @@ static void its_cpu_init_lpis(void)
>   {
>   	void __iomem *rbase = gic_data_rdist_rd_base();
>   	struct page *pend_page;
> +	struct its_node *its;
>   	phys_addr_t paddr;
>   	u64 val, tmp;
>   
> @@ -3096,6 +3107,12 @@ static void its_cpu_init_lpis(void)
>   	gicr_write_propbaser(val, rbase + GICR_PROPBASER);
>   	tmp = gicr_read_propbaser(rbase + GICR_PROPBASER);
>   
> +#if CONFIG_ROCKCHIP_NO_SHARE

ditto.

> +	its = list_first_entry(&its_nodes, struct its_node, entry);
> +	if (its->flags & ITS_FLAGS_WORKAROUND_ROCKCHIP_NOSHARE)
> +		tmp &= ~GICR_PROPBASER_SHAREABILITY_MASK;
> +#endif
> +
>   	if ((tmp ^ val) & GICR_PROPBASER_SHAREABILITY_MASK) {
>   		if (!(tmp & GICR_PROPBASER_SHAREABILITY_MASK)) {
>   			/*
> @@ -3120,6 +3137,11 @@ static void its_cpu_init_lpis(void)
>   	gicr_write_pendbaser(val, rbase + GICR_PENDBASER);
>   	tmp = gicr_read_pendbaser(rbase + GICR_PENDBASER);
>   
> +#if CONFIG_ROCKCHIP_NO_SHARE
> +	if (its->flags & ITS_FLAGS_WORKAROUND_ROCKCHIP_NOSHARE)
> +		tmp &= ~GICR_PENDBASER_SHAREABILITY_MASK;
> +#endif
> +
>   	if (!(tmp & GICR_PENDBASER_SHAREABILITY_MASK)) {
>   		/*
>   		 * The HW reports non-shareable, we must remove the
> @@ -4710,6 +4732,14 @@ static bool __maybe_unused its_enable_quirk_hip07_161600802(void *data)
>   	return true;
>   }
>   
> +static bool __maybe_unused its_enable_quirk_rk356x(void *data)
> +{
> +	struct its_node *its = data;
> +
> +	its->flags |= ITS_FLAGS_WORKAROUND_ROCKCHIP_NOSHARE;
> +	return true;
> +}
> +
>   static const struct gic_quirk its_quirks[] = {
>   #ifdef CONFIG_CAVIUM_ERRATUM_22375
>   	{
> @@ -4755,6 +4785,14 @@ static const struct gic_quirk its_quirks[] = {
>   		.mask	= 0xffffffff,
>   		.init	= its_enable_quirk_hip07_161600802,
>   	},
> +#endif
> +#ifdef CONFIG_ROCKCHIP_NO_SHARE

here it's fine.

> +	{
> +		.desc	= "ITS: Rockchip RK356X/RK3588 doesn't support shareability",
> +		.iidr	= 0x0201743b,
> +		.mask	= 0xffffffff,
> +		.init	= its_enable_quirk_rk356x,
> +	},
>   #endif
>   	{
>   	}
> @@ -5096,6 +5134,10 @@ static int __init its_probe_one(struct resource *res,
>   	gits_write_cbaser(baser, its->base + GITS_CBASER);
>   	tmp = gits_read_cbaser(its->base + GITS_CBASER);
>   
> +#if CONFIG_ROCKCHIP_NO_SHARE

...here it's not, again.

> +	if (its->flags & ITS_FLAGS_WORKAROUND_ROCKCHIP_NOSHARE)
> +		tmp &= ~GITS_CBASER_SHAREABILITY_MASK;
> +#endif
>   	if ((tmp ^ baser) & GITS_CBASER_SHAREABILITY_MASK) {
>   		if (!(tmp & GITS_CBASER_SHAREABILITY_MASK)) {
>   			/*


Regards,
Angelo

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Re: [RFC 1/1] irqchip/gic-v3: Add RK3588 GICR and GITS no share workaround

[Robin Murphy]

On 27/02/2023 3:18 pm, Lucas Tanure wrote:
> The GIC600 integration in RK356x, used in rk3588, doesn't support
> any of the shareability or cacheability attributes, and requires
> both values to be set to 0b00 for all the ITS and Redistributor
> tables.
> 
> Based on work of Peter Geis for the Quartz64 board.
> 
> Signed-off-by: Lucas Tanure <lucas.tanure@collabora.com>
> ---
>   Documentation/arm64/silicon-errata.rst |  4 +++
>   arch/arm64/Kconfig                     | 13 ++++++++
>   drivers/irqchip/irq-gic-v3-its.c       | 42 ++++++++++++++++++++++++++
>   3 files changed, 59 insertions(+)
> 
> diff --git a/Documentation/arm64/silicon-errata.rst b/Documentation/arm64/silicon-errata.rst
> index ec5f889d7681..b26cf8ca7d5c 100644
> --- a/Documentation/arm64/silicon-errata.rst
> +++ b/Documentation/arm64/silicon-errata.rst
> @@ -209,3 +209,7 @@ stable kernels.
>   +----------------+-----------------+-----------------+-----------------------------+
>   | Fujitsu        | A64FX           | E#010001        | FUJITSU_ERRATUM_010001      |
>   +----------------+-----------------+-----------------+-----------------------------+
> +
> ++----------------+-----------------+-----------------+-----------------------------+
> +| RockChip       | RK3588          | N/A             | ROCKCHIP_NO_SHARE           |
> ++----------------+-----------------+-----------------+-----------------------------+
> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
> index 27b2592698b0..ad3f1742052b 100644
> --- a/arch/arm64/Kconfig
> +++ b/arch/arm64/Kconfig
> @@ -1150,6 +1150,19 @@ config NVIDIA_CARMEL_CNP_ERRATUM
>   
>   	  If unsure, say Y.
>   
> +config ROCKCHIP_NO_SHARE
> +	bool "Rockchip RK3588 GIC6000 No shareability or cacheability attributes"
> +	default y
> +	help
> +	  The GIC600 integration in RK356x doesn't support any of the shareability or
> +	  cacheability attributes, and requires both values to be set to 0b00 for all
> +	  the ITS and Redistributor tables.
> +
> +	  Work around the issue by clearing the GICR_PROPBASER_SHAREABILITY_MASK from
> +	  register reads at GICR and GITS.
> +
> +	  If unsure, say Y.
> +
>   config SOCIONEXT_SYNQUACER_PREITS
>   	bool "Socionext Synquacer: Workaround for GICv3 pre-ITS"
>   	default y
> diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
> index 586271b8aa39..637e2e2a1ab1 100644
> --- a/drivers/irqchip/irq-gic-v3-its.c
> +++ b/drivers/irqchip/irq-gic-v3-its.c
> @@ -42,6 +42,7 @@
>   #define ITS_FLAGS_CMDQ_NEEDS_FLUSHING		(1ULL << 0)
>   #define ITS_FLAGS_WORKAROUND_CAVIUM_22375	(1ULL << 1)
>   #define ITS_FLAGS_WORKAROUND_CAVIUM_23144	(1ULL << 2)
> +#define ITS_FLAGS_WORKAROUND_ROCKCHIP_NOSHARE	(1ULL << 3)
>   
>   #define RDIST_FLAGS_PROPBASE_NEEDS_FLUSHING	(1 << 0)
>   #define RDIST_FLAGS_RD_TABLES_PREALLOCATED	(1 << 1)
> @@ -2359,6 +2360,15 @@ static int its_setup_baser(struct its_node *its, struct its_baser *baser,
>   	its_write_baser(its, baser, val);
>   	tmp = baser->val;
>   
> +#if CONFIG_ROCKCHIP_NO_SHARE
> +	if (its->flags & ITS_FLAGS_WORKAROUND_ROCKCHIP_NOSHARE) {
> +		if (tmp & GITS_BASER_SHAREABILITY_MASK)
> +			tmp &= ~GITS_BASER_SHAREABILITY_MASK;
> +		else
> +			gic_flush_dcache_to_poc(base, PAGE_ORDER_TO_SIZE(order));
> +	}
> +#endif
> +
>   	if ((val ^ tmp) & GITS_BASER_SHAREABILITY_MASK) {
>   		/*
>   		 * Shareability didn't stick. Just use
> @@ -3057,6 +3067,7 @@ static void its_cpu_init_lpis(void)
>   {
>   	void __iomem *rbase = gic_data_rdist_rd_base();
>   	struct page *pend_page;
> +	struct its_node *its;
>   	phys_addr_t paddr;
>   	u64 val, tmp;
>   
> @@ -3096,6 +3107,12 @@ static void its_cpu_init_lpis(void)
>   	gicr_write_propbaser(val, rbase + GICR_PROPBASER);
>   	tmp = gicr_read_propbaser(rbase + GICR_PROPBASER);
>   
> +#if CONFIG_ROCKCHIP_NO_SHARE
> +	its = list_first_entry(&its_nodes, struct its_node, entry);
> +	if (its->flags & ITS_FLAGS_WORKAROUND_ROCKCHIP_NOSHARE)
> +		tmp &= ~GICR_PROPBASER_SHAREABILITY_MASK;
> +#endif
> +
>   	if ((tmp ^ val) & GICR_PROPBASER_SHAREABILITY_MASK) {
>   		if (!(tmp & GICR_PROPBASER_SHAREABILITY_MASK)) {
>   			/*
> @@ -3120,6 +3137,11 @@ static void its_cpu_init_lpis(void)
>   	gicr_write_pendbaser(val, rbase + GICR_PENDBASER);
>   	tmp = gicr_read_pendbaser(rbase + GICR_PENDBASER);
>   
> +#if CONFIG_ROCKCHIP_NO_SHARE
> +	if (its->flags & ITS_FLAGS_WORKAROUND_ROCKCHIP_NOSHARE)
> +		tmp &= ~GICR_PENDBASER_SHAREABILITY_MASK;
> +#endif
> +
>   	if (!(tmp & GICR_PENDBASER_SHAREABILITY_MASK)) {
>   		/*
>   		 * The HW reports non-shareable, we must remove the
> @@ -4710,6 +4732,14 @@ static bool __maybe_unused its_enable_quirk_hip07_161600802(void *data)
>   	return true;
>   }
>   
> +static bool __maybe_unused its_enable_quirk_rk356x(void *data)
> +{
> +	struct its_node *its = data;
> +
> +	its->flags |= ITS_FLAGS_WORKAROUND_ROCKCHIP_NOSHARE;
> +	return true;
> +}
> +
>   static const struct gic_quirk its_quirks[] = {
>   #ifdef CONFIG_CAVIUM_ERRATUM_22375
>   	{
> @@ -4755,6 +4785,14 @@ static const struct gic_quirk its_quirks[] = {
>   		.mask	= 0xffffffff,
>   		.init	= its_enable_quirk_hip07_161600802,
>   	},
> +#endif
> +#ifdef CONFIG_ROCKCHIP_NO_SHARE
> +	{
> +		.desc	= "ITS: Rockchip RK356X/RK3588 doesn't support shareability",
> +		.iidr	= 0x0201743b,

This represents the Arm Ltd. GIC-600 implementation. It is definitely 
not Rockchip-specific, and applying this quirk to the likes of Ampere 
Altra or AWS Graviton2 would be extremely unpopular.

TBH I think this whole thing would be reasonable to handle in a generic 
manner using the now-standard "dma-noncoherent" property to override the 
driver's expectations. Given the apparent lack of clear integration 
guidelines it's only likely to continue happening.

Thanks,
Robin.

> +		.mask	= 0xffffffff,
> +		.init	= its_enable_quirk_rk356x,
> +	},
>   #endif
>   	{
>   	}
> @@ -5096,6 +5134,10 @@ static int __init its_probe_one(struct resource *res,
>   	gits_write_cbaser(baser, its->base + GITS_CBASER);
>   	tmp = gits_read_cbaser(its->base + GITS_CBASER);
>   
> +#if CONFIG_ROCKCHIP_NO_SHARE
> +	if (its->flags & ITS_FLAGS_WORKAROUND_ROCKCHIP_NOSHARE)
> +		tmp &= ~GITS_CBASER_SHAREABILITY_MASK;
> +#endif
>   	if ((tmp ^ baser) & GITS_CBASER_SHAREABILITY_MASK) {
>   		if (!(tmp & GITS_CBASER_SHAREABILITY_MASK)) {
>   			/*

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Re: [RFC 0/1] ITS fails to allocate on rk3588

[Peter Geis]

On Mon, Feb 27, 2023 at 10:18 AM Lucas Tanure
<lucas.tanure@collabora.com> wrote:
>
> I am assisting with PCIe and networking bring-up for Rock Pi 5B (RK3588).
> This chip uses the same GICv3 as RK356X but has fixed the previous
> limitation of GIC only supporting 32-bit addresses.
>
> But the implementation decision for shareability in GICR and GITS is
> still the same.
>
> I read the previous thread about this topic:
> https://lore.kernel.org/lkml/2791594e-db60-e1d0-88e5-7e5bbd98ae4d@rock-chips.com/T/#m5dbc70ff308d81e98dd0d797e23d3fbf9c353245
>
> From my understanding, the errata numbers Marc Zyngier is referring to
> are found in Arm errata documents at developer.arm.com/documentation.
> But I could not find Cavium or Broadcom pages for errata with those
> numbers in Documentation/arm64/silicon-errata.rst
>
> I could not find an errata document about this shareability issue,
> and by what Kever said in the previous thread this could be a
> RockChip design decision.
>
> Marc, as I could only find ARM errata numbers, is the errata number
> you were expecting generated by ARM only, or RockChip should issue
> a document like Arm to detail the issue?
>
> Can this shareability issue be seen as a quirk without an
> errata number?
>
> The following patch is based on the work of Peter Geis for the
> Quartz64 board and the previous thread feedback.

I see you have included rk356x in this as well. This will only work on
rk356x boards that do not exceed 4GB of ram as the on chip devices are
only 32bit addressable and the kernel by default allocates this in
highmem.

Very Respectfully,
Peter Geis

>
> Lucas Tanure (1):
>   irqchip/gic-v3: Add RK3588 GICR and GITS no share workaround
>
>  Documentation/arm64/silicon-errata.rst |  4 +++
>  arch/arm64/Kconfig                     | 13 ++++++++
>  drivers/irqchip/irq-gic-v3-its.c       | 42 ++++++++++++++++++++++++++
>  3 files changed, 59 insertions(+)
>
> --
> 2.39.2
>

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