[PATCH v2 1/2] RISC-V: Update l2 cache DT documentation to add support for SiFive FU740

[PATCH v2 1/2] RISC-V: Update l2 cache DT documentation to add support for SiFive FU740

[Yash Shah]

The L2 cache controller in SiFive FU740 has 4 ECC interrupt sources as
compared to 3 in FU540. Update the DT documentation accordingly with
"compatible" and "interrupt" property changes.

Signed-off-by: Yash Shah <yash.shah@sifive.com>
---
Changes in v2:
- Changes as per Rob Herring's request on v1
---
 .../devicetree/bindings/riscv/sifive-l2-cache.yaml | 35 ++++++++++++++++++++--
 1 file changed, 32 insertions(+), 3 deletions(-)

diff --git a/Documentation/devicetree/bindings/riscv/sifive-l2-cache.yaml b/Documentation/devicetree/bindings/riscv/sifive-l2-cache.yaml
index efc0198..749265c 100644
--- a/Documentation/devicetree/bindings/riscv/sifive-l2-cache.yaml
+++ b/Documentation/devicetree/bindings/riscv/sifive-l2-cache.yaml
@@ -27,6 +27,7 @@ select:
       items:
         - enum:
             - sifive,fu540-c000-ccache
+            - sifive,fu740-c000-ccache
 
   required:
     - compatible
@@ -34,7 +35,9 @@ select:
 properties:
   compatible:
     items:
-      - const: sifive,fu540-c000-ccache
+      - enum:
+          - sifive,fu540-c000-ccache
+          - sifive,fu740-c000-ccache
       - const: cache
 
   cache-block-size:
@@ -53,9 +56,15 @@ properties:
 
   interrupts:
     description: |
-      Must contain entries for DirError, DataError and DataFail signals.
+      Must contain 3 entries for FU540 (DirError, DataError and DataFail) or 4
+      entries for other chips (DirError, DirFail, DataError, DataFail signals)
     minItems: 3
-    maxItems: 3
+    maxItems: 4
+    items:
+      - description: DirError interrupt
+      - description: DirFail interrupt
+      - description: DataError interrupt
+      - description: DataFail interrupt
 
   reg:
     maxItems: 1
@@ -67,6 +76,26 @@ properties:
       The reference to the reserved-memory for the L2 Loosely Integrated Memory region.
       The reserved memory node should be defined as per the bindings in reserved-memory.txt.
 
+if:
+  properties:
+    compatible:
+      contains:
+        const: sifive,fu540-c000-ccache
+
+then:
+  properties:
+    interrupts:
+      description: |
+        Must contain entries for DirError, DataError and DataFail signals.
+      maxItems: 3
+
+else:
+  properties:
+    interrupts:
+      description: |
+        Must contain entries for DirError, DirFail, DataError, DataFail signals.
+      minItems: 4
+
 additionalProperties: false
 
 required:
-- 
2.7.4

[PATCH v2 2/2] RISC-V: sifive_l2_cache: Update L2 cache driver to support SiFive FU740

[Yash Shah]

SiFive FU740 has 4 ECC interrupt sources as compared to 3 in FU540.
Update the L2 cache controller driver to support this additional
interrupt in case of FU740-C000 chip.

Signed-off-by: Yash Shah <yash.shah@sifive.com>
---
 drivers/soc/sifive/sifive_l2_cache.c | 49 +++++++++++++++++++++++++++++++-----
 1 file changed, 43 insertions(+), 6 deletions(-)

diff --git a/drivers/soc/sifive/sifive_l2_cache.c b/drivers/soc/sifive/sifive_l2_cache.c
index 44d7e19..4e5e841 100644
--- a/drivers/soc/sifive/sifive_l2_cache.c
+++ b/drivers/soc/sifive/sifive_l2_cache.c
@@ -17,6 +17,10 @@
 #define SIFIVE_L2_DIRECCFIX_HIGH 0x104
 #define SIFIVE_L2_DIRECCFIX_COUNT 0x108
 
+#define SIFIVE_L2_DIRECCFAIL_LOW 0x120
+#define SIFIVE_L2_DIRECCFAIL_HIGH 0x124
+#define SIFIVE_L2_DIRECCFAIL_COUNT 0x128
+
 #define SIFIVE_L2_DATECCFIX_LOW 0x140
 #define SIFIVE_L2_DATECCFIX_HIGH 0x144
 #define SIFIVE_L2_DATECCFIX_COUNT 0x148
@@ -29,7 +33,7 @@
 #define SIFIVE_L2_WAYENABLE 0x08
 #define SIFIVE_L2_ECCINJECTERR 0x40
 
-#define SIFIVE_L2_MAX_ECCINTR 3
+#define SIFIVE_L2_MAX_ECCINTR 4
 
 static void __iomem *l2_base;
 static int g_irq[SIFIVE_L2_MAX_ECCINTR];
@@ -37,6 +41,7 @@ static struct riscv_cacheinfo_ops l2_cache_ops;
 
 enum {
 	DIR_CORR = 0,
+	DIR_UNCORR,
 	DATA_CORR,
 	DATA_UNCORR,
 };
@@ -93,6 +98,7 @@ static void l2_config_read(void)
 
 static const struct of_device_id sifive_l2_ids[] = {
 	{ .compatible = "sifive,fu540-c000-ccache" },
+	{ .compatible = "sifive,fu740-c000-ccache" },
 	{ /* end of table */ },
 };
 
@@ -155,6 +161,15 @@ static irqreturn_t l2_int_handler(int irq, void *device)
 		atomic_notifier_call_chain(&l2_err_chain, SIFIVE_L2_ERR_TYPE_CE,
 					   "DirECCFix");
 	}
+	if (irq == g_irq[DIR_UNCORR]) {
+		add_h = readl(l2_base + SIFIVE_L2_DIRECCFAIL_HIGH);
+		add_l = readl(l2_base + SIFIVE_L2_DIRECCFAIL_LOW);
+		/* Reading this register clears the DirFail interrupt sig */
+		readl(l2_base + SIFIVE_L2_DIRECCFAIL_COUNT);
+		atomic_notifier_call_chain(&l2_err_chain, SIFIVE_L2_ERR_TYPE_UE,
+					   "DirECCFail");
+		panic("L2CACHE: DirFail @ 0x%08X.%08X\n", add_h, add_l);
+	}
 	if (irq == g_irq[DATA_CORR]) {
 		add_h = readl(l2_base + SIFIVE_L2_DATECCFIX_HIGH);
 		add_l = readl(l2_base + SIFIVE_L2_DATECCFIX_LOW);
@@ -179,9 +194,9 @@ static irqreturn_t l2_int_handler(int irq, void *device)
 
 static int __init sifive_l2_init(void)
 {
+	int i, k, rc, intr_num, offset = 0;
 	struct device_node *np;
 	struct resource res;
-	int i, rc;
 
 	np = of_find_matching_node(NULL, sifive_l2_ids);
 	if (!np)
@@ -194,11 +209,33 @@ static int __init sifive_l2_init(void)
 	if (!l2_base)
 		return -ENOMEM;
 
-	for (i = 0; i < SIFIVE_L2_MAX_ECCINTR; i++) {
-		g_irq[i] = irq_of_parse_and_map(np, i);
-		rc = request_irq(g_irq[i], l2_int_handler, 0, "l2_ecc", NULL);
+	intr_num = of_property_count_u32_elems(np, "interrupts");
+	if (!intr_num) {
+		pr_err("L2CACHE: no interrupts property\n");
+		return -ENODEV;
+	}
+
+	/*
+	 * Only FU540 have 3 interrupts. Rest all other variants have
+	 * 4 interrupts (+dirfail). Therefore offset is required to skip
+	 * 'dirfail' interrupt entry in case of FU540
+	 */
+	if (of_device_is_compatible(np, "sifive,fu540-c000-ccache"))
+		offset = 1;
+
+	g_irq[0] = irq_of_parse_and_map(np, 0);
+	rc = request_irq(g_irq[0], l2_int_handler, 0, "l2_ecc", NULL);
+	if (rc) {
+		pr_err("L2CACHE: Could not request IRQ %d\n", g_irq[0]);
+		return rc;
+	}
+
+	for (i = 1; i < intr_num; i++) {
+		k = i + offset;
+		g_irq[k] = irq_of_parse_and_map(np, i);
+		rc = request_irq(g_irq[k], l2_int_handler, 0, "l2_ecc", NULL);
 		if (rc) {
-			pr_err("L2CACHE: Could not request IRQ %d\n", g_irq[i]);
+			pr_err("L2CACHE: Could not request IRQ %d\n", g_irq[k]);
 			return rc;
 		}
 	}
-- 
2.7.4

Re: [PATCH v2 1/2] RISC-V: Update l2 cache DT documentation to add support for SiFive FU740

[Rob Herring]

On Mon, Nov 30, 2020 at 11:13:03AM +0530, Yash Shah wrote:
> The L2 cache controller in SiFive FU740 has 4 ECC interrupt sources as
> compared to 3 in FU540. Update the DT documentation accordingly with
> "compatible" and "interrupt" property changes.

'dt-bindings: riscv: ...' for the subject.

> 
> Signed-off-by: Yash Shah <yash.shah@sifive.com>
> ---
> Changes in v2:
> - Changes as per Rob Herring's request on v1
> ---
>  .../devicetree/bindings/riscv/sifive-l2-cache.yaml | 35 ++++++++++++++++++++--
>  1 file changed, 32 insertions(+), 3 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/riscv/sifive-l2-cache.yaml b/Documentation/devicetree/bindings/riscv/sifive-l2-cache.yaml
> index efc0198..749265c 100644
> --- a/Documentation/devicetree/bindings/riscv/sifive-l2-cache.yaml
> +++ b/Documentation/devicetree/bindings/riscv/sifive-l2-cache.yaml
> @@ -27,6 +27,7 @@ select:
>        items:
>          - enum:
>              - sifive,fu540-c000-ccache
> +            - sifive,fu740-c000-ccache
>  
>    required:
>      - compatible
> @@ -34,7 +35,9 @@ select:
>  properties:
>    compatible:
>      items:
> -      - const: sifive,fu540-c000-ccache
> +      - enum:
> +          - sifive,fu540-c000-ccache
> +          - sifive,fu740-c000-ccache
>        - const: cache
>  
>    cache-block-size:
> @@ -53,9 +56,15 @@ properties:
>  
>    interrupts:
>      description: |
> -      Must contain entries for DirError, DataError and DataFail signals.
> +      Must contain 3 entries for FU540 (DirError, DataError and DataFail) or 4
> +      entries for other chips (DirError, DirFail, DataError, DataFail signals)

While below is wrong, don't give descriptions that just repeat what the 
schema says.

>      minItems: 3
> -    maxItems: 3
> +    maxItems: 4
> +    items:
> +      - description: DirError interrupt
> +      - description: DirFail interrupt
> +      - description: DataError interrupt
> +      - description: DataFail interrupt

This says DataFail is optional.

>  
>    reg:
>      maxItems: 1
> @@ -67,6 +76,26 @@ properties:
>        The reference to the reserved-memory for the L2 Loosely Integrated Memory region.
>        The reserved memory node should be defined as per the bindings in reserved-memory.txt.
>  
> +if:
> +  properties:
> +    compatible:
> +      contains:
> +        const: sifive,fu540-c000-ccache
> +
> +then:
> +  properties:
> +    interrupts:
> +      description: |
> +        Must contain entries for DirError, DataError and DataFail signals.
> +      maxItems: 3
> +
> +else:
> +  properties:
> +    interrupts:
> +      description: |
> +        Must contain entries for DirError, DirFail, DataError, DataFail signals.
> +      minItems: 4
> +
>  additionalProperties: false
>  
>  required:
> -- 
> 2.7.4
> 

RE: [PATCH v2 1/2] RISC-V: Update l2 cache DT documentation to add support for SiFive FU740

[Yash Shah]

> -----Original Message-----
> From: Rob Herring <robh@kernel.org>
> Sent: 09 December 2020 04:52
> To: Yash Shah <yash.shah@openfive.com>
> Cc: linux-kernel@vger.kernel.org; linux-riscv@lists.infradead.org;
> devicetree@vger.kernel.org; bp@suse.de; anup@brainfault.org;
> Jonathan.Cameron@huawei.com; wsa@kernel.org; sam@ravnborg.org;
> aou@eecs.berkeley.edu; palmer@dabbelt.com; Paul Walmsley ( Sifive)
> <paul.walmsley@sifive.com>; Sagar Kadam <sagar.kadam@openfive.com>;
> Sachin Ghadi <sachin.ghadi@openfive.com>
> Subject: Re: [PATCH v2 1/2] RISC-V: Update l2 cache DT documentation to
> add support for SiFive FU740
> 
> [External Email] Do not click links or attachments unless you recognize the
> sender and know the content is safe
> 
> On Mon, Nov 30, 2020 at 11:13:03AM +0530, Yash Shah wrote:
> > The L2 cache controller in SiFive FU740 has 4 ECC interrupt sources as
> > compared to 3 in FU540. Update the DT documentation accordingly with
> > "compatible" and "interrupt" property changes.
> 
> 'dt-bindings: riscv: ...' for the subject.
> 
> >
> > Signed-off-by: Yash Shah <yash.shah@sifive.com>
> > ---
> > Changes in v2:
> > - Changes as per Rob Herring's request on v1
> > ---
> >  .../devicetree/bindings/riscv/sifive-l2-cache.yaml | 35
> > ++++++++++++++++++++--
> >  1 file changed, 32 insertions(+), 3 deletions(-)
> >
> > diff --git
> > a/Documentation/devicetree/bindings/riscv/sifive-l2-cache.yaml
> > b/Documentation/devicetree/bindings/riscv/sifive-l2-cache.yaml
> > index efc0198..749265c 100644
> > --- a/Documentation/devicetree/bindings/riscv/sifive-l2-cache.yaml
> > +++ b/Documentation/devicetree/bindings/riscv/sifive-l2-cache.yaml
> > @@ -27,6 +27,7 @@ select:
> >        items:
> >          - enum:
> >              - sifive,fu540-c000-ccache
> > +            - sifive,fu740-c000-ccache
> >
> >    required:
> >      - compatible
> > @@ -34,7 +35,9 @@ select:
> >  properties:
> >    compatible:
> >      items:
> > -      - const: sifive,fu540-c000-ccache
> > +      - enum:
> > +          - sifive,fu540-c000-ccache
> > +          - sifive,fu740-c000-ccache
> >        - const: cache
> >
> >    cache-block-size:
> > @@ -53,9 +56,15 @@ properties:
> >
> >    interrupts:
> >      description: |
> > -      Must contain entries for DirError, DataError and DataFail signals.
> > +      Must contain 3 entries for FU540 (DirError, DataError and DataFail) or
> 4
> > +      entries for other chips (DirError, DirFail, DataError, DataFail
> > + signals)
> 
> While below is wrong, don't give descriptions that just repeat what the
> schema says.

Ok will remove the above description.

> 
> >      minItems: 3
> > -    maxItems: 3
> > +    maxItems: 4
> > +    items:
> > +      - description: DirError interrupt
> > +      - description: DirFail interrupt
> > +      - description: DataError interrupt
> > +      - description: DataFail interrupt
> 
> This says DataFail is optional.

I will move back to your initial suggestion to add the new entry "DirFail" as the last index to keep the order same.
Will make the corresponding changes in the driver and send a v3 patch.

Thanks for your review.

- Yash