Re: [PATCH v6 4/7] ARM: l2c: Add support for overriding prefetch settings
On Mon, Oct 27, 2014 at 12:19:34PM +0100, Marek Szyprowski wrote: Hello, On 2014-10-27 12:14, Russell King - ARM Linux wrote: On Mon, Oct 27, 2014 at 12:05:47PM +0100, Marek Szyprowski wrote: From: Tomasz Figa t.f...@samsung.com Firmware on certain boards (e.g. ODROID-U3) can leave incorrect L2C prefetch settings configured in registers leading to crashes if L2C is enabled without overriding them. This patch introduces bindings to enable prefetch settings to be specified from DT and necessary support in the driver. Signed-off-by: Tomasz Figa t.f...@samsung.com [mszyprow: rebased onto v3.18-rc1, added error messages when property value is missing] Why? What if the boot loader has already set these up appropriately? Why should we force people to list these in the DT? The error message is displayed only when user provided prefetch related properties without any value (empty properties). Something that Mark Rutland requested here: https://lkml.org/lkml/2014/9/24/426 I'm sorry if I didn't describe it clearly enough. Ok. I'd ask for one change. Please make all these messages start with L2C-310 OF not PL310 OF:. The device is described in ARM documentation as a L2C-310 not PL310. (Also note the : is dropped too - most of the other messages don't have the : either.) The: PL310 OF: cache setting yield illegal associativity PL310 OF: -1073346556 calculated, only 8 and 16 legal message could also be changed to something like: L2C-310 OF cache associativity %d invalid, only 8 or 16 permitted\n Thanks. -- FTTC broadband for 0.8mile line: currently at 9.5Mbps down 400kbps up according to speedtest.net. -- To unsubscribe from this list: send the line unsubscribe linux-samsung-soc in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH v6 4/7] ARM: l2c: Add support for overriding prefetch settings
On Tue, Oct 28, 2014 at 9:35 AM, Russell King - ARM Linux li...@arm.linux.org.uk wrote: Ok. I'd ask for one change. Please make all these messages start with L2C-310 OF not PL310 OF:. The device is described in ARM documentation as a L2C-310 not PL310. (Also note the : is dropped too - most of the other messages don't have the : either.) The: PL310 OF: cache setting yield illegal associativity PL310 OF: -1073346556 calculated, only 8 and 16 legal I have sent a patch to address this error message that happens when cache-size and cache-sets properties are not passed in DT: http://www.spinics.net/lists/arm-kernel/msg372094.html -- To unsubscribe from this list: send the line unsubscribe linux-samsung-soc in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
[PATCH v6 4/7] ARM: l2c: Add support for overriding prefetch settings
From: Tomasz Figa t.f...@samsung.com
Firmware on certain boards (e.g. ODROID-U3) can leave incorrect L2C prefetch
settings configured in registers leading to crashes if L2C is enabled
without overriding them. This patch introduces bindings to enable
prefetch settings to be specified from DT and necessary support in the
driver.
Signed-off-by: Tomasz Figa t.f...@samsung.com
[mszyprow: rebased onto v3.18-rc1, added error messages when property value
is missing]
Signed-off-by: Marek Szyprowski m.szyprow...@samsung.com
---
Documentation/devicetree/bindings/arm/l2cc.txt | 10 +
arch/arm/mm/cache-l2x0.c | 55 ++
2 files changed, 65 insertions(+)
diff --git a/Documentation/devicetree/bindings/arm/l2cc.txt
b/Documentation/devicetree/bindings/arm/l2cc.txt
index 292ef7ca3058..0dbabe9a6b0a 100644
--- a/Documentation/devicetree/bindings/arm/l2cc.txt
+++ b/Documentation/devicetree/bindings/arm/l2cc.txt
@@ -57,6 +57,16 @@ Optional properties:
- cache-id-part: cache id part number to be used if it is not present
on hardware
- wt-override: If present then L2 is forced to Write through mode
+- arm,double-linefill : Override double linefill enable setting. Enable if
+ non-zero, disable if zero.
+- arm,double-linefill-incr : Override double linefill on INCR read. Enable
+ if non-zero, disable if zero.
+- arm,double-linefill-wrap : Override double linefill on WRAP read. Enable
+ if non-zero, disable if zero.
+- arm,prefetch-drop : Override prefetch drop enable setting. Enable if
non-zero,
+ disable if zero.
+- arm,prefetch-offset : Override prefetch offset value. Valid values are
+ 0-7, 15, 23, and 31.
Example:
diff --git a/arch/arm/mm/cache-l2x0.c b/arch/arm/mm/cache-l2x0.c
index ad981894de73..69cfa8359ed3 100644
--- a/arch/arm/mm/cache-l2x0.c
+++ b/arch/arm/mm/cache-l2x0.c
@@ -1163,6 +1163,9 @@ static void __init l2c310_of_parse(const struct
device_node *np,
u32 tag[3] = { 0, 0, 0 };
u32 filter[2] = { 0, 0 };
u32 assoc;
+ u32 prefetch;
+ u32 val;
+ int ret;
of_property_read_u32_array(np, arm,tag-latency, tag, ARRAY_SIZE(tag));
if (tag[0] tag[1] tag[2])
@@ -1204,6 +1207,58 @@ static void __init l2c310_of_parse(const struct
device_node *np,
pr_err(PL310 OF: %d calculated, only 8 and 16 legal\n, assoc);
break;
}
+
+ prefetch = l2x0_saved_regs.prefetch_ctrl;
+
+ ret = of_property_read_u32(np, arm,double-linefill, val);
+ if (ret == 0) {
+ if (val)
+ prefetch |= L310_PREFETCH_CTRL_DBL_LINEFILL;
+ else
+ prefetch = ~L310_PREFETCH_CTRL_DBL_LINEFILL;
+ } else if (ret != -EINVAL) {
+ pr_err(PL310 OF: missing value for arm,double-linefill
property\n);
+ }
+
+ ret = of_property_read_u32(np, arm,double-linefill-incr, val);
+ if (ret == 0) {
+ if (val)
+ prefetch |= L310_PREFETCH_CTRL_DBL_LINEFILL_INCR;
+ else
+ prefetch = ~L310_PREFETCH_CTRL_DBL_LINEFILL_INCR;
+ } else if (ret != -EINVAL) {
+ pr_err(PL310 OF: missing value for arm,double-linefill-incr
property\n);
+ }
+
+ ret = of_property_read_u32(np, arm,double-linefill-wrap, val);
+ if (ret == 0) {
+ if (!val)
+ prefetch |= L310_PREFETCH_CTRL_DBL_LINEFILL_WRAP;
+ else
+ prefetch = ~L310_PREFETCH_CTRL_DBL_LINEFILL_WRAP;
+ } else if (ret != -EINVAL) {
+ pr_err(PL310 OF: missing value for arm,double-linefill-wrap
property\n);
+ }
+
+ ret = of_property_read_u32(np, arm,prefetch-drop, val);
+ if (ret == 0) {
+ if (val)
+ prefetch |= L310_PREFETCH_CTRL_PREFETCH_DROP;
+ else
+ prefetch = ~L310_PREFETCH_CTRL_PREFETCH_DROP;
+ } else if (ret != -EINVAL) {
+ pr_err(PL310 OF: missing value for arm,prefetch-drop
property\n);
+ }
+
+ ret = of_property_read_u32(np, arm,prefetch-offset, val);
+ if (ret == 0) {
+ prefetch = ~L310_PREFETCH_CTRL_OFFSET_MASK;
+ prefetch |= val L310_PREFETCH_CTRL_OFFSET_MASK;
+ } else if (ret != -EINVAL) {
+ pr_err(PL310 OF: missing value for arm,prefetch-offset
property\n);
+ }
+
+ l2x0_saved_regs.prefetch_ctrl = prefetch;
}
static const struct l2c_init_data of_l2c310_data __initconst = {
--
1.9.2
--
To unsubscribe from this list: send the line unsubscribe linux-samsung-soc in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH v6 4/7] ARM: l2c: Add support for overriding prefetch settings
On Mon, Oct 27, 2014 at 12:05:47PM +0100, Marek Szyprowski wrote: From: Tomasz Figa t.f...@samsung.com Firmware on certain boards (e.g. ODROID-U3) can leave incorrect L2C prefetch settings configured in registers leading to crashes if L2C is enabled without overriding them. This patch introduces bindings to enable prefetch settings to be specified from DT and necessary support in the driver. Signed-off-by: Tomasz Figa t.f...@samsung.com [mszyprow: rebased onto v3.18-rc1, added error messages when property value is missing] Why? What if the boot loader has already set these up appropriately? Why should we force people to list these in the DT? -- FTTC broadband for 0.8mile line: currently at 9.5Mbps down 400kbps up according to speedtest.net. -- To unsubscribe from this list: send the line unsubscribe linux-samsung-soc in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH v6 4/7] ARM: l2c: Add support for overriding prefetch settings
Hello, On 2014-10-27 12:14, Russell King - ARM Linux wrote: On Mon, Oct 27, 2014 at 12:05:47PM +0100, Marek Szyprowski wrote: From: Tomasz Figa t.f...@samsung.com Firmware on certain boards (e.g. ODROID-U3) can leave incorrect L2C prefetch settings configured in registers leading to crashes if L2C is enabled without overriding them. This patch introduces bindings to enable prefetch settings to be specified from DT and necessary support in the driver. Signed-off-by: Tomasz Figa t.f...@samsung.com [mszyprow: rebased onto v3.18-rc1, added error messages when property value is missing] Why? What if the boot loader has already set these up appropriately? Why should we force people to list these in the DT? The error message is displayed only when user provided prefetch related properties without any value (empty properties). Something that Mark Rutland requested here: https://lkml.org/lkml/2014/9/24/426 I'm sorry if I didn't describe it clearly enough. Best regards -- Marek Szyprowski, PhD Samsung RD Institute Poland -- To unsubscribe from this list: send the line unsubscribe linux-samsung-soc in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
