On 11/30/2016 11:35 AM, Grygorii Strashko wrote:
>
>
> On 11/30/2016 03:56 AM, Richard Cochran wrote:
>> On Mon, Nov 28, 2016 at 05:04:24PM -0600, Grygorii Strashko wrote:
>>> Some CPTS instances, which can be found on KeyStone 2 1/10G Ethernet
>>> Switch Subsystems, can control an external multiplexer that selects
>>> one of up to 32 clocks for time sync reference (RFTCLK). This feature
>>> can be configured through CPTS_RFTCLK_SEL register (offset: x08).
>>>
>>> Hence, introduce optional DT cpts_rftclk_sel poperty wich, if present,
>>> will specify CPTS reference clock. The cpts_rftclk_sel should be
>>> omitted in DT if HW doesn't support this feature. The external fixed
>>> rate clocks can be defined in board files as "fixed-clock".
>>
>> Can't you implement this using the clock tree, rather than an ad-hoc
>> DT property?
>>
>
> I've thought about this, but decided to move forward with this impl
> which is pretty simple. I will try.
>
>
I come with below RFC patch. if no objection I'll move forward with it.
According to Keystone 2 66AK2e DM there are 7 possible ref clocks:
0000 = SYSCLK2
0001 = SYSCLK3
0010 = TIMI0
0011 = TIMI1
0100 = TSIPCLKA
1000 = TSREFCLK
1100 = TSIPCLKB
Others = Reserved
2 from above clocks are internal SYSCLK2 and SYSCLK3 - other external
(board specific). So default definition of cpts_mux will have only two parents.
If ext clock is going to be use as cpts rftclk then it should be
defined in board file and cpts_refclk_mux definition updated to support
this ext clock:
timi1clk: timi1clk {
#clock-cells = <0>;
compatible = "fixed-clock";
clock-frequency = <xxxxxxxxxx>;
clock-output-names = "timi1";
};
&cpts_mux {
clocks = <&chipclk12>, <&chipclk13>, <timi1clk>;
cpts-mux-tbl = <0>, <1>, <3>;
assigned-clocks = <&cpts_mux>;
assigned-clock-parents = <&timi1clk>;
};
>From ec5c7bed0e021c2ca7e9392173bf67bb9a45d0f4 Mon Sep 17 00:00:00 2001
From: Grygorii Strashko <grygorii.strashko@xxxxxx>
Date: Mon, 5 Dec 2016 12:34:45 -0600
Subject: [PATCH] cpts refclk sel
Signed-off-by: Grygorii Strashko <grygorii.strashko@xxxxxx>
---
arch/arm/boot/dts/keystone-k2e-netcp.dtsi | 10 +++++-
drivers/net/ethernet/ti/cpts.c | 52 ++++++++++++++++++++++++++++++-
2 files changed, 60 insertions(+), 2 deletions(-)
diff --git a/arch/arm/boot/dts/keystone-k2e-netcp.dtsi b/arch/arm/boot/dts/keystone-k2e-netcp.dtsi
index 919e655..b27aa22 100644
--- a/arch/arm/boot/dts/keystone-k2e-netcp.dtsi
+++ b/arch/arm/boot/dts/keystone-k2e-netcp.dtsi
@@ -138,7 +138,7 @@ netcp: netcp@24000000 {
/* NetCP address range */
ranges = <0 0x24000000 0x1000000>;
- clocks = <&clkpa>, <&clkcpgmac>, <&chipclk12>;
+ clocks = <&clkpa>, <&clkcpgmac>, <&cpts_mux>;
clock-names = "pa_clk", "ethss_clk", "cpts";
dma-coherent;
@@ -162,6 +162,14 @@ netcp: netcp@24000000 {
cpts-ext-ts-inputs = <6>;
cpts-ts-comp-length;
+ cpts_mux: cpts_refclk_mux {
+ #clock-cells = <0>;
+ clocks = <&chipclk12>, <&chipclk13>;
+ cpts-mux-tbl = <0>, <1>;
+ assigned-clocks = <&cpts_mux>;
+ assigned-clock-parents = <&chipclk12>;
+ };
+
interfaces {
gbe0: interface-0 {
slave-port = <0>;
diff --git a/drivers/net/ethernet/ti/cpts.c b/drivers/net/ethernet/ti/cpts.c
index 938de22..ef94316 100644
--- a/drivers/net/ethernet/ti/cpts.c
+++ b/drivers/net/ethernet/ti/cpts.c
@@ -17,6 +17,7 @@
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
+#include <linux/clk-provider.h>
#include <linux/err.h>
#include <linux/if.h>
#include <linux/hrtimer.h>
@@ -672,6 +673,7 @@ int cpts_register(struct cpts *cpts)
cpts->phc_index = ptp_clock_index(cpts->clock);
schedule_delayed_work(&cpts->overflow_work, cpts->ov_check_period);
+
return 0;
err_ptp:
@@ -741,6 +743,54 @@ static void cpts_calc_mult_shift(struct cpts *cpts)
freq, cpts->cc_mult, cpts->cc.shift, (ns - NSEC_PER_SEC));
}
+static int cpts_of_mux_clk_setup(struct cpts *cpts, struct device_node *node)
+{
+ unsigned int num_parents;
+ const char **parent_names;
+ struct device_node *refclk_np;
+ void __iomem *reg;
+ struct clk *clk;
+ u32 *mux_table;
+ int ret;
+
+ refclk_np = of_get_child_by_name(node, "cpts_refclk_mux");
+ if (!refclk_np)
+ return -EINVAL;
+
+ num_parents = of_clk_get_parent_count(refclk_np);
+ if (num_parents < 1) {
+ dev_err(cpts->dev, "mux-clock %s must have parents\n",
+ refclk_np->name);
+ return -EINVAL;
+ }
+ parent_names = devm_kzalloc(cpts->dev, (sizeof(char *) * num_parents),
+ GFP_KERNEL);
+ if (!parent_names)
+ return -ENOMEM;
+
+ of_clk_parent_fill(refclk_np, parent_names, num_parents);
+
+ mux_table = devm_kzalloc(cpts->dev, sizeof(*mux_table) * (32 + 1),
+ GFP_KERNEL);
+ if (!mux_table)
+ return -ENOMEM;
+
+ ret = of_property_read_variable_u32_array(refclk_np, "cpts-mux-tbl",
+ mux_table, 1, 32);
+ if (ret < 0)
+ return ret;
+
+ reg = &cpts->reg->rftclk_sel;
+
+ clk = clk_register_mux_table(cpts->dev, refclk_np->name,
+ parent_names, num_parents,
+ 0, reg, 0, 0x1F, 0, mux_table, NULL);
+ if (IS_ERR(clk))
+ return PTR_ERR(clk);
+
+ return of_clk_add_provider(refclk_np, of_clk_src_simple_get, clk);
+}
+
static int cpts_of_parse(struct cpts *cpts, struct device_node *node)
{
int ret = -EINVAL;
@@ -787,7 +837,7 @@ static int cpts_of_parse(struct cpts *cpts, struct device_node *node)
if (!of_property_read_u32(node, "cpts-ext-ts-inputs", &prop))
cpts->ext_ts_inputs = prop;
- return 0;
+ return cpts_of_mux_clk_setup(cpts, node);
of_error:
dev_err(cpts->dev, "CPTS: Missing property in the DT.\n");
--
2.10.1
--
regards,
-grygorii
--
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