[PATCH 0/4] dt: device tree support for TI EMIF driver

[PATCH 0/4] dt: device tree support for TI EMIF driver

[Aneesh V]

This series adds device tree support for TI EMIF SDRAM controller
driver. For this, a binding has been added for representing AC timing
parameters and other details of LPDDR2 memories.

This series depends my series for adding EMIF driver [1]

[1] http://marc.info/?l=linux-omap&m=133122243430942&w=2

Aneesh V (4):
  dt: device tree bindings for LPDDR2 memories
  dt: emif: device tree bindings for TI's EMIF sdram controller
  arm: dts: EMIF and LPDDR2 device tree data for OMAP4 boards
  misc: emif: add device tree support to emif driver

 .../devicetree/bindings/lpddr2/lpddr2-timings.txt  |   52 ++++
 .../devicetree/bindings/lpddr2/lpddr2.txt          |  102 +++++++
 .../bindings/memory-controllers/ti/emif.txt        |   55 ++++
 arch/arm/boot/dts/elpida_ecb240abacn.dtsi          |   67 +++++
 arch/arm/boot/dts/omap4-panda.dts                  |   13 +
 arch/arm/boot/dts/omap4-sdp.dts                    |   13 +
 arch/arm/boot/dts/omap4.dtsi                       |   18 ++
 drivers/misc/emif.c                                |  289 +++++++++++++++++++-
 8 files changed, 608 insertions(+), 1 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/lpddr2/lpddr2-timings.txt
 create mode 100644 Documentation/devicetree/bindings/lpddr2/lpddr2.txt
 create mode 100644 Documentation/devicetree/bindings/memory-controllers/ti/emif.txt
 create mode 100644 arch/arm/boot/dts/elpida_ecb240abacn.dtsi

[PATCH 1/4] dt: device tree bindings for LPDDR2 memories

[Aneesh V]

device tree bindings for LPDDR2 SDRAM memories compliant
to JESD209-2 standard.

The 'lpddr2' binding in-turn uses another binding 'lpddr2-timings'
for specifying the AC timing parameters of the memory device at
different speed-bins.

Cc: Rajendra Nayak <rnayak@ti.com>
Cc: Benoit Cousson <b-cousson@ti.com>
Signed-off-by: Aneesh V <aneesh@ti.com>
---
Changes since RFC v4:
- Removed two DDR3 only timing parameters that were
  inadvertently added in the binding
---
 .../devicetree/bindings/lpddr2/lpddr2-timings.txt  |   52 ++++++++++
 .../devicetree/bindings/lpddr2/lpddr2.txt          |  102 ++++++++++++++++++++
 2 files changed, 154 insertions(+), 0 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/lpddr2/lpddr2-timings.txt
 create mode 100644 Documentation/devicetree/bindings/lpddr2/lpddr2.txt

diff --git a/Documentation/devicetree/bindings/lpddr2/lpddr2-timings.txt b/Documentation/devicetree/bindings/lpddr2/lpddr2-timings.txt
new file mode 100644
index 0000000..a48f698
--- /dev/null
+++ b/Documentation/devicetree/bindings/lpddr2/lpddr2-timings.txt
@@ -0,0 +1,52 @@
+* AC timing parameters of LPDDR2(JESD209-2) memories for a given speed-bin
+
+Required properties:
+- compatible : Should be "jedec,lpddr2-timings"
+- min-freq : minimum DDR clock frequency for the speed-bin. Type is <u32>
+- max-freq : maximum DDR clock frequency for the speed-bin. Type is <u32>
+
+Optional properties:
+
+The following properties represent AC timing parameters from the memory
+data-sheet of the device for a given speed-bin. All these properties are
+of type <u32> and the default unit is ps (pico seconds). Parameters with
+a different unit have a suffix indicating the unit such as 'tRAS-max-ns'
+- tRCD
+- tWR
+- tRAS-min
+- tRRD
+- tWTR
+- tXP
+- tRTP
+- tDQSCK-max
+- tFAW
+- tZQCS
+- tZQinit
+- tRPab
+- tZQCL
+- tCKESR
+- tRAS-max-ns
+- tDQSCK-max-derated
+
+Example:
+
+timings_elpida_ECB240ABACN_400mhz: lpddr2-timings at 0 {
+	compatible 	= "jedec,lpddr2-timings";
+	min-freq	= <10000000>;
+	max-freq	= <400000000>;
+	tRPab		= <21000>;
+	tRCD		= <18000>;
+	tWR		= <15000>;
+	tRAS-min	= <42000>;
+	tRRD		= <10000>;
+	tWTR		= <7500>;
+	tXP		= <7500>;
+	tRTP		= <7500>;
+	tCKESR		= <15000>;
+	tDQSCK-max 	= <5500>;
+	tFAW		= <50000>;
+	tZQCS		= <90000>;
+	tZQCL		= <360000>;
+	tZQinit		= <1000000>;
+	tRAS-max-ns	= <70000>;
+};
diff --git a/Documentation/devicetree/bindings/lpddr2/lpddr2.txt b/Documentation/devicetree/bindings/lpddr2/lpddr2.txt
new file mode 100644
index 0000000..a2ab203
--- /dev/null
+++ b/Documentation/devicetree/bindings/lpddr2/lpddr2.txt
@@ -0,0 +1,102 @@
+* LPDDR2 SDRAM memories compliant to JEDEC JESD209-2
+
+Required properties:
+- compatible : Should be one of - "jedec,lpddr2-nvm", "jedec,lpddr2-s2",
+  "jedec,lpddr2-s4"
+
+  "ti,jedec-lpddr2-s2" should be listed if the memory part is LPDDR2-S2 type
+
+  "ti,jedec-lpddr2-s4" should be listed if the memory part is LPDDR2-S4 type
+
+  "ti,jedec-lpddr2-nvm" should be listed if the memory part is LPDDR2-NVM type
+
+- density  : <u32> representing density in Mb (Mega bits)
+
+- io-width : <u32> representing bus width. Possible values are 8, 16, and 32
+
+Optional properties:
+
+The following optional properties represent the minimum value of some AC
+timing parameters of the DDR device in terms of number of clock cycles.
+These values shall be obtained from the device data-sheet.
+- tRRD-min-tck
+- tWTR-min-tck
+- tXP-min-tck
+- tRTP-min-tck
+- tCKE-min-tck
+- tRPab-min-tck
+- tRCD-min-tck
+- tWR-min-tck
+- tRASmin-min-tck
+- tCKESR-min-tck
+- tFAW-min-tck
+
+Child nodes:
+- The lpddr2 node may have one or more child nodes of type "lpddr2-timings".
+  "lpddr2-timings" provides AC timing parameters of the device for
+  a given speed-bin. The user may provide the timings for as many
+  speed-bins as is required. Please see Documentation/devicetree/
+  bindings/lpddr2/lpddr2-timings.txt for more information on "lpddr2-timings"
+
+Example:
+
+elpida_ECB240ABACN : lpddr2 {
+	compatible 	= "Elpida,ECB240ABACN","jedec,lpddr2-s4";
+	density		= <2048>;
+	io-width	= <32>;
+
+	tRPab-min-tck	= <3>;
+	tRCD-min-tck	= <3>;
+	tWR-min-tck	= <3>;
+	tRASmin-min-tck	= <3>;
+	tRRD-min-tck	= <2>;
+	tWTR-min-tck	= <2>;
+	tXP-min-tck	= <2>;
+	tRTP-min-tck	= <2>;
+	tCKE-min-tck	= <3>;
+	tCKESR-min-tck	= <3>;
+	tFAW-min-tck	= <8>;
+
+	timings_elpida_ECB240ABACN_400mhz: lpddr2-timings at 0 {
+		compatible 	= "jedec,lpddr2-timings";
+		min-freq	= <10000000>;
+		max-freq	= <400000000>;
+		tRPab		= <21000>;
+		tRCD		= <18000>;
+		tWR		= <15000>;
+		tRAS-min	= <42000>;
+		tRRD		= <10000>;
+		tWTR		= <7500>;
+		tXP		= <7500>;
+		tRTP		= <7500>;
+		tCKESR		= <15000>;
+		tDQSCK-max 	= <5500>;
+		tFAW		= <50000>;
+		tZQCS		= <90000>;
+		tZQCL		= <360000>;
+		tZQinit		= <1000000>;
+		tRAS-max-ns	= <70000>;
+	};
+
+	timings_elpida_ECB240ABACN_200mhz: lpddr2-timings at 1 {
+		compatible 	= "jedec,lpddr2-timings";
+		min-freq	= <10000000>;
+		max-freq	= <200000000>;
+		tRPab		= <21000>;
+		tRCD		= <18000>;
+		tWR		= <15000>;
+		tRAS-min	= <42000>;
+		tRRD		= <10000>;
+		tWTR		= <10000>;
+		tXP		= <7500>;
+		tRTP		= <7500>;
+		tCKESR		= <15000>;
+		tDQSCK-max 	= <5500>;
+		tFAW		= <50000>;
+		tZQCS		= <90000>;
+		tZQCL		= <360000>;
+		tZQinit		= <1000000>;
+		tRAS-max-ns	= <70000>;
+	};
+
+}
-- 
1.7.1

[PATCH 2/4] dt: emif: device tree bindings for TI's EMIF sdram controller

[Aneesh V]

EMIF - External Memory Interface - is an SDRAM controller used in
TI SoCs. EMIF supports, based on the IP revision, one or more of
DDR2/DDR3/LPDDR2 protocols. This binding describes a given instance
of the EMIF IP and memory parts attached to it.

Cc: Rajendra Nayak <rnayak@ti.com>
Cc: Benoit Cousson <b-cousson@ti.com>
Signed-off-by: Aneesh V <aneesh@ti.com>
---
Changes sice RFC v4:
- None
---
 .../bindings/memory-controllers/ti/emif.txt        |   55 ++++++++++++++++++++
 1 files changed, 55 insertions(+), 0 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/memory-controllers/ti/emif.txt

diff --git a/Documentation/devicetree/bindings/memory-controllers/ti/emif.txt b/Documentation/devicetree/bindings/memory-controllers/ti/emif.txt
new file mode 100644
index 0000000..938f8e1
--- /dev/null
+++ b/Documentation/devicetree/bindings/memory-controllers/ti/emif.txt
@@ -0,0 +1,55 @@
+* EMIF family of TI SDRAM controllers
+
+EMIF - External Memory Interface - is an SDRAM controller used in
+TI SoCs. EMIF supports, based on the IP revision, one or more of
+DDR2/DDR3/LPDDR2 protocols. This binding describes a given instance
+of the EMIF IP and memory parts attached to it.
+
+Required properties:
+- compatible	: Should be of the form "ti,emif-<ip-rev>" where <ip-rev>
+  is the IP revision of the specific EMIF instance.
+
+- phy-type	: <u32> indicating the DDR phy type. Following are the
+  allowed values
+  <1>	: Attila PHY
+  <2>	: Intelli PHY
+
+- device-handle	: phandle to a "lpddr2" node representing the memory part
+
+- ti,hwmods	: For TI hwmods processing and omap device creation
+  the value shall be "emif<n>" where <n> is the number of the EMIF
+  instance with base 1.
+
+Optional properties:
+- cs1-used		: Have this property if CS1 of this EMIF
+  instance has a memory part attached to it. If there is a memory
+  part attached to CS1, it should be the same type as the one on CS0,
+  so there is no need to give the details of this memory part.
+
+- cal-resistor-per-cs	: Have this property if the board has one
+  calibration resistor per chip-select.
+
+- hw-caps-read-idle-ctrl: Have this property if the controller
+  supports read idle window programming
+
+- hw-caps-dll-calib-ctrl: Have this property if the controller
+  supports dll calibration control
+
+- hw-caps-ll-interface	: Have this property if the controller
+  has a low latency interface and corresponding interrupt events
+
+- hw-caps-temp-alert	: Have this property if the controller
+  has capability for generating SDRAM temperature alerts
+
+Example:
+
+emif1: emif at 0x4c000000 {
+	compatible	= "ti,emif-4d";
+	ti,hwmods	= "emif2";
+	phy-type	= <1>;
+	device-handle	= <&elpida_ECB240ABACN>;
+	cs1-used;
+	hw-caps-read-idle-ctrl;
+	hw-caps-ll-interface;
+	hw-caps-temp-alert;
+};
-- 
1.7.1

[PATCH 3/4] arm: dts: EMIF and LPDDR2 device tree data for OMAP4 boards

[Aneesh V]

Device tree data for the EMIF sdram controllers in OMAP4
and LPDDR2 memory devices attached to OMAP4 boards.

Cc: Rajendra Nayak <rnayak@ti.com>
Cc: Benoit Cousson <b-cousson@ti.com>
Signed-off-by: Aneesh V <aneesh@ti.com>
---
Changes since RFC v4:
- Removed DDR3 only parameters from
  elpida_ecb240abacn.dtsi
---
 arch/arm/boot/dts/elpida_ecb240abacn.dtsi |   67 +++++++++++++++++++++++++++++
 arch/arm/boot/dts/omap4-panda.dts         |   13 ++++++
 arch/arm/boot/dts/omap4-sdp.dts           |   13 ++++++
 arch/arm/boot/dts/omap4.dtsi              |   18 ++++++++
 4 files changed, 111 insertions(+), 0 deletions(-)
 create mode 100644 arch/arm/boot/dts/elpida_ecb240abacn.dtsi

diff --git a/arch/arm/boot/dts/elpida_ecb240abacn.dtsi b/arch/arm/boot/dts/elpida_ecb240abacn.dtsi
new file mode 100644
index 0000000..34b9f72
--- /dev/null
+++ b/arch/arm/boot/dts/elpida_ecb240abacn.dtsi
@@ -0,0 +1,67 @@
+/*
+ * Common devices used in different OMAP boards
+ */
+
+/ {
+	elpida_ECB240ABACN: lpddr2 {
+		compatible 	= "Elpida,ECB240ABACN","jedec,lpddr2-s4";
+		density		= <2048>;
+		io-width	= <32>;
+
+		tRPab-min-tck	= <3>;
+		tRCD-min-tck	= <3>;
+		tWR-min-tck	= <3>;
+		tRASmin-min-tck	= <3>;
+		tRRD-min-tck	= <2>;
+		tWTR-min-tck	= <2>;
+		tXP-min-tck	= <2>;
+		tRTP-min-tck	= <2>;
+		tCKE-min-tck	= <3>;
+		tCKESR-min-tck	= <3>;
+		tFAW-min-tck	= <8>;
+
+		timings_elpida_ECB240ABACN_400mhz: lpddr2-timings at 0 {
+			compatible	= "jedec,lpddr2-timings";
+			min-freq	= <10000000>;
+			max-freq	= <400000000>;
+			tRPab		= <21000>;
+			tRCD		= <18000>;
+			tWR		= <15000>;
+			tRAS-min	= <42000>;
+			tRRD		= <10000>;
+			tWTR		= <7500>;
+			tXP		= <7500>;
+			tRTP		= <7500>;
+			tCKESR		= <15000>;
+			tDQSCK-max 	= <5500>;
+			tFAW		= <50000>;
+			tZQCS		= <90000>;
+			tZQCL		= <360000>;
+			tZQinit		= <1000000>;
+			tRAS-max-ns	= <70000>;
+			tDQSCK-max-derated = <6000>;
+		};
+
+		timings_elpida_ECB240ABACN_200mhz: lpddr2-timings at 1 {
+			compatible	= "jedec,lpddr2-timings";
+			min-freq	= <10000000>;
+			max-freq	= <200000000>;
+			tRPab		= <21000>;
+			tRCD		= <18000>;
+			tWR		= <15000>;
+			tRAS-min	= <42000>;
+			tRRD		= <10000>;
+			tWTR		= <10000>;
+			tXP		= <7500>;
+			tRTP		= <7500>;
+			tCKESR		= <15000>;
+			tDQSCK-max 	= <5500>;
+			tFAW		= <50000>;
+			tZQCS		= <90000>;
+			tZQCL		= <360000>;
+			tZQinit		= <1000000>;
+			tRAS-max-ns	= <70000>;
+			tDQSCK-max-derated = <6000>;
+		};
+	};
+};
diff --git a/arch/arm/boot/dts/omap4-panda.dts b/arch/arm/boot/dts/omap4-panda.dts
index 9755ad5..f548523 100644
--- a/arch/arm/boot/dts/omap4-panda.dts
+++ b/arch/arm/boot/dts/omap4-panda.dts
@@ -8,6 +8,7 @@
 /dts-v1/;
 
 /include/ "omap4.dtsi"
+/include/ "elpida_ecb240abacn.dtsi"
 
 / {
 	model = "TI OMAP4 PandaBoard";
@@ -17,4 +18,16 @@
 		device_type = "memory";
 		reg = <0x80000000 0x40000000>; /* 1 GB */
 	};
+
+	ocp {
+		emif1: emif at 0x4c000000 {
+			cs1-used;
+			device-handle = <&elpida_ECB240ABACN>;
+		};
+
+		emif2: emif at 0x4d000000 {
+			cs1-used;
+			device-handle = <&elpida_ECB240ABACN>;
+		};
+	};
 };
diff --git a/arch/arm/boot/dts/omap4-sdp.dts b/arch/arm/boot/dts/omap4-sdp.dts
index 63c6b2b..6dc08bc 100644
--- a/arch/arm/boot/dts/omap4-sdp.dts
+++ b/arch/arm/boot/dts/omap4-sdp.dts
@@ -8,6 +8,7 @@
 /dts-v1/;
 
 /include/ "omap4.dtsi"
+/include/ "elpida_ecb240abacn.dtsi"
 
 / {
 	model = "TI OMAP4 SDP board";
@@ -17,4 +18,16 @@
 		device_type = "memory";
 		reg = <0x80000000 0x40000000>; /* 1 GB */
 	};
+
+	ocp {
+		emif1: emif at 0x4c000000 {
+			cs1-used;
+			device-handle = <&elpida_ECB240ABACN>;
+		};
+
+		emif2: emif at 0x4d000000 {
+			cs1-used;
+			device-handle = <&elpida_ECB240ABACN>;
+		};
+	};
 };
diff --git a/arch/arm/boot/dts/omap4.dtsi b/arch/arm/boot/dts/omap4.dtsi
index 70a44f6..fe3664a 100644
--- a/arch/arm/boot/dts/omap4.dtsi
+++ b/arch/arm/boot/dts/omap4.dtsi
@@ -127,5 +127,23 @@
 			ti,hwmods = "uart4";
 			clock-frequency = <48000000>;
 		};
+
+		emif1: emif at 0x4c000000 {
+			compatible	= "ti,emif-4d";
+			ti,hwmods	= "emif1";
+			phy-type	= <1>;
+			hw-caps-read-idle-ctrl;
+			hw-caps-ll-interface;
+			hw-caps-temp-alert;
+		};
+
+		emif2: emif at 0x4d000000 {
+			compatible	= "ti,emif-4d";
+			ti,hwmods	= "emif2";
+			phy-type	= <1>;
+			hw-caps-read-idle-ctrl;
+			hw-caps-ll-interface;
+			hw-caps-temp-alert;
+		};
 	};
 };
-- 
1.7.1

[PATCH 4/4] misc: emif: add device tree support to emif driver

[Aneesh V]

Cc: Rajendra Nayak <rnayak@ti.com>
Cc: Benoit Cousson <b-cousson@ti.com>
Signed-off-by: Aneesh V <aneesh@ti.com>
---
Changes since RFC v4:
- Rebased to the latest version of EMIF series
- Replace kzalloc()/kfree() with devm_* variants
---
 drivers/misc/emif.c |  289 ++++++++++++++++++++++++++++++++++++++++++++++++++-
 1 files changed, 288 insertions(+), 1 deletions(-)

diff --git a/drivers/misc/emif.c b/drivers/misc/emif.c
index 79fb161..0aaa61e 100644
--- a/drivers/misc/emif.c
+++ b/drivers/misc/emif.c
@@ -18,6 +18,7 @@
 #include <linux/platform_device.h>
 #include <linux/interrupt.h>
 #include <linux/slab.h>
+#include <linux/of.h>
 #include <linux/debugfs.h>
 #include <linux/seq_file.h>
 #include <linux/module.h>
@@ -49,6 +50,7 @@
  *				frequency in effect at the moment)
  * @plat_data:			Pointer to saved platform data.
  * @debugfs_root:		dentry to the root folder for EMIF in debugfs
+ * @np_ddr:			Pointer to ddr device tree node
  */
 struct emif_data {
 	u8				duplicate;
@@ -63,6 +65,9 @@ struct emif_data {
 	struct emif_regs		*curr_regs;
 	struct emif_platform_data	*plat_data;
 	struct dentry			*debugfs_root;
+#if defined(CONFIG_OF)
+	struct device_node		*np_ddr;
+#endif
 };
 
 static struct emif_data *emif1;
@@ -1147,6 +1152,270 @@ static int is_custom_config_valid(struct emif_custom_configs *cust_cfgs,
 	return valid;
 }
 
+#if defined(CONFIG_OF)
+static void __init of_get_custom_configs(struct device_node *np_emif,
+		struct emif_data *emif)
+{
+	struct emif_custom_configs	*cust_cfgs = NULL;
+	int				len;
+	const int			*lpmode, *poll_intvl;
+
+	lpmode = of_get_property(np_emif, "low-power-mode", &len);
+	poll_intvl = of_get_property(np_emif, "temp-alert-poll-interval", &len);
+
+	if (lpmode || poll_intvl)
+		cust_cfgs = devm_kzalloc(emif->dev, sizeof(*cust_cfgs),
+			GFP_KERNEL);
+
+	if (!cust_cfgs)
+		return;
+
+	if (lpmode) {
+		cust_cfgs->mask |= EMIF_CUSTOM_CONFIG_LPMODE;
+		cust_cfgs->lpmode = *lpmode;
+		of_property_read_u32(np_emif,
+				"low-power-mode-timeout-performance",
+				&cust_cfgs->lpmode_timeout_performance);
+		of_property_read_u32(np_emif,
+				"low-power-mode-timeout-power",
+				&cust_cfgs->lpmode_timeout_power);
+		of_property_read_u32(np_emif,
+				"low-power-mode-freq-threshold",
+				&cust_cfgs->lpmode_freq_threshold);
+	}
+
+	if (poll_intvl) {
+		cust_cfgs->mask |=
+				EMIF_CUSTOM_CONFIG_TEMP_ALERT_POLL_INTERVAL;
+		cust_cfgs->temp_alert_poll_interval_ms = *poll_intvl;
+	}
+
+	if (!is_custom_config_valid(cust_cfgs, emif->dev)) {
+		devm_kfree(emif->dev, cust_cfgs);
+		return;
+	}
+
+	emif->plat_data->custom_configs = cust_cfgs;
+}
+
+static void __init of_get_min_tck(struct device_node *np,
+		struct emif_data *emif)
+{
+	int			ret = 0;
+	struct lpddr2_min_tck	*min;
+
+	min = devm_kzalloc(emif->dev, sizeof(*min), GFP_KERNEL);
+	if (!min)
+		goto default_min_tck;
+
+	ret |= of_property_read_u32(np, "tRPab-min-tck", &min->tRPab);
+	ret |= of_property_read_u32(np, "tRCD-min-tck", &min->tRCD);
+	ret |= of_property_read_u32(np, "tWR-min-tck", &min->tWR);
+	ret |= of_property_read_u32(np, "tRASmin-min-tck", &min->tRASmin);
+	ret |= of_property_read_u32(np, "tRRD-min-tck", &min->tRRD);
+	ret |= of_property_read_u32(np, "tWTR-min-tck", &min->tWTR);
+	ret |= of_property_read_u32(np, "tXP-min-tck", &min->tXP);
+	ret |= of_property_read_u32(np, "tRTP-min-tck", &min->tRTP);
+	ret |= of_property_read_u32(np, "tCKE-min-tck", &min->tCKE);
+	ret |= of_property_read_u32(np, "tCKESR-min-tck", &min->tCKESR);
+	ret |= of_property_read_u32(np, "tFAW-min-tck", &min->tFAW);
+
+	if (ret) {
+		devm_kfree(emif->dev, min);
+		goto default_min_tck;
+	}
+
+	emif->plat_data->min_tck = min;
+	return;
+
+default_min_tck:
+	dev_warn(emif->dev, "%s: using default min-tck values\n", __func__);
+	emif->plat_data->min_tck = &lpddr2_min_tck;
+}
+
+static int __init of_do_get_timings(struct device_node *np,
+		struct lpddr2_timings *tim)
+{
+	int ret;
+
+	ret = of_property_read_u32(np, "max-freq", &tim->max_freq);
+	ret |= of_property_read_u32(np, "min-freq", &tim->min_freq);
+	ret |= of_property_read_u32(np, "tRPab", &tim->tRPab);
+	ret |= of_property_read_u32(np, "tRCD", &tim->tRCD);
+	ret |= of_property_read_u32(np, "tWR", &tim->tWR);
+	ret |= of_property_read_u32(np, "tRAS-min", &tim->tRAS_min);
+	ret |= of_property_read_u32(np, "tRRD", &tim->tRRD);
+	ret |= of_property_read_u32(np, "tWTR", &tim->tWTR);
+	ret |= of_property_read_u32(np, "tXP", &tim->tXP);
+	ret |= of_property_read_u32(np, "tRTP", &tim->tRTP);
+	ret |= of_property_read_u32(np, "tCKESR", &tim->tCKESR);
+	ret |= of_property_read_u32(np, "tDQSCK-max", &tim->tDQSCK_max);
+	ret |= of_property_read_u32(np, "tFAW", &tim->tFAW);
+	ret |= of_property_read_u32(np, "tZQCS", &tim->tZQCS);
+	ret |= of_property_read_u32(np, "tZQCL", &tim->tZQCL);
+	ret |= of_property_read_u32(np, "tZQinit", &tim->tZQinit);
+	ret |= of_property_read_u32(np, "tRAS-max-ns", &tim->tRAS_max_ns);
+	ret |= of_property_read_u32(np, "tDQSCK-max-derated",
+		&tim->tDQSCK_max_derated);
+
+	return ret;
+}
+
+static void __init of_get_ddr_timings(struct device_node *np_ddr,
+		struct emif_data *emif)
+{
+	struct lpddr2_timings	*timings = NULL;
+	u32			arr_sz = 0, i = 0;
+	struct device_node	*np_tim;
+	char			*tim_compat;
+
+	switch (emif->plat_data->device_info->type) {
+	case DDR_TYPE_LPDDR2_S2:
+	case DDR_TYPE_LPDDR2_S4:
+		tim_compat = "jedec,lpddr2-timings";
+		break;
+	default:
+		dev_warn(emif->dev, "%s: un-supported memory type\n", __func__);
+	}
+
+	for_each_child_of_node(np_ddr, np_tim)
+		if (of_device_is_compatible(np_tim, tim_compat))
+			arr_sz++;
+
+	if (arr_sz)
+		timings = devm_kzalloc(emif->dev, sizeof(*timings) * arr_sz,
+			GFP_KERNEL);
+
+	if (!timings)
+		goto default_timings;
+
+	for_each_child_of_node(np_ddr, np_tim) {
+		if (of_device_is_compatible(np_tim, tim_compat)) {
+			if (of_do_get_timings(np_tim, &timings[i])) {
+				devm_kfree(emif->dev, timings);
+				goto default_timings;
+			}
+			i++;
+		}
+	}
+
+	emif->plat_data->timings = timings;
+	emif->plat_data->timings_arr_size = arr_sz;
+
+	return;
+
+default_timings:
+	get_default_timings(emif);
+
+	return;
+}
+
+static void __init of_get_ddr_info(struct device_node *np_emif,
+		struct device_node *np_ddr,
+		struct ddr_device_info *dev_info)
+{
+	u32 density = 0, io_width = 0;
+	int len;
+
+	if (of_find_property(np_emif, "cs1-used", &len))
+		dev_info->cs1_used = true;
+
+	if (of_find_property(np_emif, "cal-resistor-per-cs", &len))
+		dev_info->cal_resistors_per_cs = true;
+
+	if (of_device_is_compatible(np_ddr , "jedec,lpddr2-s4"))
+		dev_info->type = DDR_TYPE_LPDDR2_S4;
+	else if (of_device_is_compatible(np_ddr , "jedec,lpddr2-s2"))
+		dev_info->type = DDR_TYPE_LPDDR2_S2;
+
+	of_property_read_u32(np_ddr, "density", &density);
+	of_property_read_u32(np_ddr, "io-width", &io_width);
+
+	/* Convert from density in Mb to the density encoding in jedc_ddr.h */
+	if (density & (density - 1))
+		dev_info->density = 0;
+	else
+		dev_info->density = __fls(density) - 5;
+
+	/* Convert from io_width in bits to io_width encoding in jedc_ddr.h */
+	if (io_width & (io_width - 1))
+		dev_info->io_width = 0;
+	else
+		dev_info->io_width = __fls(io_width) - 1;
+}
+
+static struct emif_data * __init of_get_device_details(
+		struct device_node *np_emif, struct device *dev)
+{
+	struct emif_data		*emif = NULL;
+	struct ddr_device_info		*dev_info = NULL;
+	struct emif_platform_data	*pd = NULL;
+	struct device_node		*np_ddr;
+	int				len;
+
+	np_ddr = of_parse_phandle(np_emif, "device-handle", 0);
+	if (!np_ddr)
+		goto error;
+	emif	= devm_kzalloc(dev, sizeof(struct emif_data), GFP_KERNEL);
+	pd	= devm_kzalloc(dev, sizeof(*pd), GFP_KERNEL);
+	dev_info = devm_kzalloc(dev, sizeof(*dev_info), GFP_KERNEL);
+
+	if (!emif || !pd || !dev_info) {
+		dev_err(dev, "%s: of_get_device_details() failure!!\n",
+			__func__);
+		goto error;
+	}
+
+	emif->plat_data		= pd;
+	pd->device_info		= dev_info;
+	emif->dev		= dev;
+	emif->np_ddr		= np_ddr;
+	emif->temperature_level	= SDRAM_TEMP_NOMINAL;
+
+	if (of_device_is_compatible(np_emif, "ti,emif-4d"))
+		emif->plat_data->ip_rev = EMIF_4D;
+	else if (of_device_is_compatible(np_emif, "ti,emif-4d5"))
+		emif->plat_data->ip_rev = EMIF_4D5;
+
+	of_property_read_u32(np_emif, "phy-type", &pd->phy_type);
+
+	if (of_find_property(np_emif, "hw-caps-ll-interface", &len))
+		pd->hw_caps |= EMIF_HW_CAPS_LL_INTERFACE;
+
+	of_get_ddr_info(np_emif, np_ddr, dev_info);
+	if (!is_dev_data_valid(pd->device_info->type, pd->device_info->density,
+			pd->device_info->io_width, pd->phy_type, pd->ip_rev,
+			emif->dev)) {
+		dev_err(dev, "%s: invalid device data!!\n", __func__);
+		goto error;
+	}
+	/*
+	 * For EMIF instances other than EMIF1 see if the devices connected
+	 * are exactly same as on EMIF1(which is typically the case). If so,
+	 * mark it as a duplicate of EMIF1. This will save some memory and
+	 * computation.
+	 */
+	if (emif1 && emif1->np_ddr == np_ddr) {
+		emif->duplicate = true;
+		goto out;
+	} else if (emif1) {
+		dev_warn(emif->dev, "%s: Non-symmetric DDR geometry\n",
+			__func__);
+	}
+
+
+	of_get_custom_configs(np_emif, emif);
+	of_get_ddr_timings(np_ddr, emif);
+	of_get_min_tck(np_ddr, emif);
+	goto out;
+
+error:
+	return NULL;
+out:
+	return emif;
+}
+#endif
+
 static struct emif_data * __init get_device_details(
 		struct platform_device *pdev)
 {
@@ -1266,7 +1535,13 @@ static int __init emif_probe(struct platform_device *pdev)
 	struct resource		*res;
 	int			irq;
 
-	emif = get_device_details(pdev);
+#if defined(CONFIG_OF)
+	if (pdev->dev.of_node)
+		emif = of_get_device_details(pdev->dev.of_node, &pdev->dev);
+	else
+#endif
+		emif = get_device_details(pdev);
+
 	if (!emif) {
 		pr_err("%s: error getting device data\n", __func__);
 		goto error;
@@ -1643,11 +1918,23 @@ static void __attribute__((unused)) freq_post_notify_handling(void)
 	spin_unlock_irqrestore(&emif_lock, irq_state);
 }
 
+#if defined(CONFIG_OF)
+static const struct of_device_id emif_of_match[] = {
+		{ .compatible = "ti,emif-4d" },
+		{ .compatible = "ti,emif-4d5" },
+		{},
+};
+MODULE_DEVICE_TABLE(of, emif_of_match);
+#endif
+
 static struct platform_driver emif_driver = {
 	.remove		= __exit_p(emif_remove),
 	.shutdown	= emif_shutdown,
 	.driver = {
 		.name = "emif",
+#if defined(CONFIG_OF)
+		.of_match_table = of_match_ptr(emif_of_match),
+#endif
 	},
 };
 
-- 
1.7.1

[PATCH 4/4] misc: emif: add device tree support to emif driver

[Grant Likely]

On Thu,  8 Mar 2012 22:03:57 +0530, Aneesh V <aneesh@ti.com> wrote:
> Cc: Rajendra Nayak <rnayak@ti.com>
> Cc: Benoit Cousson <b-cousson@ti.com>
> Signed-off-by: Aneesh V <aneesh@ti.com>
> ---
> Changes since RFC v4:
> - Rebased to the latest version of EMIF series
> - Replace kzalloc()/kfree() with devm_* variants
> ---
>  drivers/misc/emif.c |  289 ++++++++++++++++++++++++++++++++++++++++++++++++++-
>  1 files changed, 288 insertions(+), 1 deletions(-)
> 
> diff --git a/drivers/misc/emif.c b/drivers/misc/emif.c
> index 79fb161..0aaa61e 100644
> --- a/drivers/misc/emif.c
> +++ b/drivers/misc/emif.c
> @@ -18,6 +18,7 @@
>  #include <linux/platform_device.h>
>  #include <linux/interrupt.h>
>  #include <linux/slab.h>
> +#include <linux/of.h>
>  #include <linux/debugfs.h>
>  #include <linux/seq_file.h>
>  #include <linux/module.h>
> @@ -49,6 +50,7 @@
>   *				frequency in effect at the moment)
>   * @plat_data:			Pointer to saved platform data.
>   * @debugfs_root:		dentry to the root folder for EMIF in debugfs
> + * @np_ddr:			Pointer to ddr device tree node
>   */
>  struct emif_data {
>  	u8				duplicate;
> @@ -63,6 +65,9 @@ struct emif_data {
>  	struct emif_regs		*curr_regs;
>  	struct emif_platform_data	*plat_data;
>  	struct dentry			*debugfs_root;
> +#if defined(CONFIG_OF)
> +	struct device_node		*np_ddr;
> +#endif

Don't bother with the #if/#endif wrapper here.

>  };
>  
>  static struct emif_data *emif1;
> @@ -1147,6 +1152,270 @@ static int is_custom_config_valid(struct emif_custom_configs *cust_cfgs,
>  	return valid;
>  }
>  
> +#if defined(CONFIG_OF)
> +static void __init of_get_custom_configs(struct device_node *np_emif,

__devinit. Same through the rest of the file.

[...]
> +	return NULL;
> +out:
> +	return emif;
> +}
> +#endif
> +
>  static struct emif_data * __init get_device_details(

This function also must be __devinit

>  		struct platform_device *pdev)
>  {
> @@ -1266,7 +1535,13 @@ static int __init emif_probe(struct platform_device *pdev)
>  	struct resource		*res;
>  	int			irq;
>  
> -	emif = get_device_details(pdev);
> +#if defined(CONFIG_OF)
> +	if (pdev->dev.of_node)
> +		emif = of_get_device_details(pdev->dev.of_node, &pdev->dev);
> +	else
> +#endif
> +		emif = get_device_details(pdev);
> +
>  	if (!emif) {
>  		pr_err("%s: error getting device data\n", __func__);
>  		goto error;
> @@ -1643,11 +1918,23 @@ static void __attribute__((unused)) freq_post_notify_handling(void)
>  	spin_unlock_irqrestore(&emif_lock, irq_state);
>  }
>  
> +#if defined(CONFIG_OF)
> +static const struct of_device_id emif_of_match[] = {
> +		{ .compatible = "ti,emif-4d" },
> +		{ .compatible = "ti,emif-4d5" },
> +		{},
> +};
> +MODULE_DEVICE_TABLE(of, emif_of_match);
> +#endif
> +
>  static struct platform_driver emif_driver = {
>  	.remove		= __exit_p(emif_remove),

Not part of this patch I realize, but this is a bug.  .remove must
be in the __devexit section and the __devexit_p() wrapper must
be used.  Similarly, emif_probe must be in the __devinit section.

>  	.shutdown	= emif_shutdown,
>  	.driver = {
>  		.name = "emif",
> +#if defined(CONFIG_OF)
> +		.of_match_table = of_match_ptr(emif_of_match),
> +#endif

The of_match_ptr() macro makes the #if/#endif wrapper redundant.

Otherwise, on brief review this patch looks right.

g.


>  	},
>  };
>  
> -- 
> 1.7.1
> 
> 
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel at lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

-- 
Grant Likely, B.Sc, P.Eng.
Secret Lab Technologies,Ltd.

[PATCH 4/4] misc: emif: add device tree support to emif driver

[Aneesh V]

Hi Grant,

On Friday 09 March 2012 11:07 AM, Grant Likely wrote:
> On Thu,  8 Mar 2012 22:03:57 +0530, Aneesh V<aneesh@ti.com>  wrote:
>> Cc: Rajendra Nayak<rnayak@ti.com>
>> Cc: Benoit Cousson<b-cousson@ti.com>
>> Signed-off-by: Aneesh V<aneesh@ti.com>
>> ---
>> Changes since RFC v4:
>> - Rebased to the latest version of EMIF series
>> - Replace kzalloc()/kfree() with devm_* variants
>> ---
>>   drivers/misc/emif.c |  289 ++++++++++++++++++++++++++++++++++++++++++++++++++-
>>   1 files changed, 288 insertions(+), 1 deletions(-)
>>
>> diff --git a/drivers/misc/emif.c b/drivers/misc/emif.c
>> index 79fb161..0aaa61e 100644
>> --- a/drivers/misc/emif.c
>> +++ b/drivers/misc/emif.c
>> @@ -18,6 +18,7 @@
>>   #include<linux/platform_device.h>
>>   #include<linux/interrupt.h>
>>   #include<linux/slab.h>
>> +#include<linux/of.h>
>>   #include<linux/debugfs.h>
>>   #include<linux/seq_file.h>
>>   #include<linux/module.h>
>> @@ -49,6 +50,7 @@
>>    *				frequency in effect at the moment)
>>    * @plat_data:			Pointer to saved platform data.
>>    * @debugfs_root:		dentry to the root folder for EMIF in debugfs
>> + * @np_ddr:			Pointer to ddr device tree node
>>    */
>>   struct emif_data {
>>   	u8				duplicate;
>> @@ -63,6 +65,9 @@ struct emif_data {
>>   	struct emif_regs		*curr_regs;
>>   	struct emif_platform_data	*plat_data;
>>   	struct dentry			*debugfs_root;
>> +#if defined(CONFIG_OF)
>> +	struct device_node		*np_ddr;
>> +#endif
>
> Don't bother with the #if/#endif wrapper here.

Ok.

>
>>   };
>>
>>   static struct emif_data *emif1;
>> @@ -1147,6 +1152,270 @@ static int is_custom_config_valid(struct emif_custom_configs *cust_cfgs,
>>   	return valid;
>>   }
>>
>> +#if defined(CONFIG_OF)
>> +static void __init of_get_custom_configs(struct device_node *np_emif,
>
> __devinit. Same through the rest of the file.

I am not sure if we need __devinit. I see that __devinit will not have
any effect if CONFIG_HOTPLUG is enabled and CONFIG_HOTPLUG is always
enabled in our configuration. EMIF devices are not hot-pluggable
devices and are always added at boot-time from the board file. They are
on-chip IP modules and dynamic discovery and addition doesn't make
sense for them. So, can't we save some memory by making them __init.

AFAIU, __init doesn't have any effect in a module. However, I can make
that more explicit by using '__init_or_module'. Is that ok?

>
> [...]
>> +	return NULL;
>> +out:
>> +	return emif;
>> +}
>> +#endif
>> +
>>   static struct emif_data * __init get_device_details(
>
> This function also must be __devinit
>
>>   		struct platform_device *pdev)
>>   {
>> @@ -1266,7 +1535,13 @@ static int __init emif_probe(struct platform_device *pdev)
>>   	struct resource		*res;
>>   	int			irq;
>>
>> -	emif = get_device_details(pdev);
>> +#if defined(CONFIG_OF)
>> +	if (pdev->dev.of_node)
>> +		emif = of_get_device_details(pdev->dev.of_node,&pdev->dev);
>> +	else
>> +#endif
>> +		emif = get_device_details(pdev);
>> +
>>   	if (!emif) {
>>   		pr_err("%s: error getting device data\n", __func__);
>>   		goto error;
>> @@ -1643,11 +1918,23 @@ static void __attribute__((unused)) freq_post_notify_handling(void)
>>   	spin_unlock_irqrestore(&emif_lock, irq_state);
>>   }
>>
>> +#if defined(CONFIG_OF)
>> +static const struct of_device_id emif_of_match[] = {
>> +		{ .compatible = "ti,emif-4d" },
>> +		{ .compatible = "ti,emif-4d5" },
>> +		{},
>> +};
>> +MODULE_DEVICE_TABLE(of, emif_of_match);
>> +#endif
>> +
>>   static struct platform_driver emif_driver = {
>>   	.remove		= __exit_p(emif_remove),
>
> Not part of this patch I realize, but this is a bug.  .remove must
> be in the __devexit section and the __devexit_p() wrapper must
> be used.  Similarly, emif_probe must be in the __devinit section.

Again, in our case remove() is not needed unless the driver is built as
a module because the devices will never be un-registered. When it is
built as a module the effect is same for both:

#if defined(MODULE) || defined(CONFIG_HOTPLUG)
#define __devexit_p(x) x
#else
#define __devexit_p(x) NULL
#endif

#ifdef MODULE
#define __exit_p(x) x
#else
#define __exit_p(x) NULL
#endif

>
>>   	.shutdown	= emif_shutdown,
>>   	.driver = {
>>   		.name = "emif",
>> +#if defined(CONFIG_OF)
>> +		.of_match_table = of_match_ptr(emif_of_match),
>> +#endif
>
> The of_match_ptr() macro makes the #if/#endif wrapper redundant.

Ok. I will remove it.

>
> Otherwise, on brief review this patch looks right.

Thanks for the review. Are you ok with the bindings too?

br,
Aneesh

[PATCH 4/4] misc: emif: add device tree support to emif driver

[Grant Likely]

On Fri, 09 Mar 2012 18:20:51 +0530, Aneesh V <aneesh@ti.com> wrote:
> Hi Grant,
> 
> On Friday 09 March 2012 11:07 AM, Grant Likely wrote:
> > On Thu,  8 Mar 2012 22:03:57 +0530, Aneesh V<aneesh@ti.com>  wrote:
> >> Cc: Rajendra Nayak<rnayak@ti.com>
> >> Cc: Benoit Cousson<b-cousson@ti.com>
> >> Signed-off-by: Aneesh V<aneesh@ti.com>
> >> ---
> >> Changes since RFC v4:
> >> - Rebased to the latest version of EMIF series
> >> - Replace kzalloc()/kfree() with devm_* variants
> >> ---
> >>   drivers/misc/emif.c |  289 ++++++++++++++++++++++++++++++++++++++++++++++++++-
> >>   1 files changed, 288 insertions(+), 1 deletions(-)
> >>
> >> diff --git a/drivers/misc/emif.c b/drivers/misc/emif.c
> >> index 79fb161..0aaa61e 100644
> >> --- a/drivers/misc/emif.c
> >> +++ b/drivers/misc/emif.c
> >> @@ -18,6 +18,7 @@
> >>   #include<linux/platform_device.h>
> >>   #include<linux/interrupt.h>
> >>   #include<linux/slab.h>
> >> +#include<linux/of.h>
> >>   #include<linux/debugfs.h>
> >>   #include<linux/seq_file.h>
> >>   #include<linux/module.h>
> >> @@ -49,6 +50,7 @@
> >>    *				frequency in effect at the moment)
> >>    * @plat_data:			Pointer to saved platform data.
> >>    * @debugfs_root:		dentry to the root folder for EMIF in debugfs
> >> + * @np_ddr:			Pointer to ddr device tree node
> >>    */
> >>   struct emif_data {
> >>   	u8				duplicate;
> >> @@ -63,6 +65,9 @@ struct emif_data {
> >>   	struct emif_regs		*curr_regs;
> >>   	struct emif_platform_data	*plat_data;
> >>   	struct dentry			*debugfs_root;
> >> +#if defined(CONFIG_OF)
> >> +	struct device_node		*np_ddr;
> >> +#endif
> >
> > Don't bother with the #if/#endif wrapper here.
> 
> Ok.
> 
> >
> >>   };
> >>
> >>   static struct emif_data *emif1;
> >> @@ -1147,6 +1152,270 @@ static int is_custom_config_valid(struct emif_custom_configs *cust_cfgs,
> >>   	return valid;
> >>   }
> >>
> >> +#if defined(CONFIG_OF)
> >> +static void __init of_get_custom_configs(struct device_node *np_emif,
> >
> > __devinit. Same through the rest of the file.
> 
> I am not sure if we need __devinit. I see that __devinit will not have
> any effect if CONFIG_HOTPLUG is enabled and CONFIG_HOTPLUG is always
> enabled in our configuration. EMIF devices are not hot-pluggable
> devices and are always added at boot-time from the board file. They are
> on-chip IP modules and dynamic discovery and addition doesn't make
> sense for them. So, can't we save some memory by making them __init.
> 
> AFAIU, __init doesn't have any effect in a module. However, I can make
> that more explicit by using '__init_or_module'. Is that ok?
> 
> >
> > [...]
> >> +	return NULL;
> >> +out:
> >> +	return emif;
> >> +}
> >> +#endif
> >> +
> >>   static struct emif_data * __init get_device_details(
> >
> > This function also must be __devinit
> >
> >>   		struct platform_device *pdev)
> >>   {
> >> @@ -1266,7 +1535,13 @@ static int __init emif_probe(struct platform_device *pdev)
> >>   	struct resource		*res;
> >>   	int			irq;
> >>
> >> -	emif = get_device_details(pdev);
> >> +#if defined(CONFIG_OF)
> >> +	if (pdev->dev.of_node)
> >> +		emif = of_get_device_details(pdev->dev.of_node,&pdev->dev);
> >> +	else
> >> +#endif
> >> +		emif = get_device_details(pdev);
> >> +
> >>   	if (!emif) {
> >>   		pr_err("%s: error getting device data\n", __func__);
> >>   		goto error;
> >> @@ -1643,11 +1918,23 @@ static void __attribute__((unused)) freq_post_notify_handling(void)
> >>   	spin_unlock_irqrestore(&emif_lock, irq_state);
> >>   }
> >>
> >> +#if defined(CONFIG_OF)
> >> +static const struct of_device_id emif_of_match[] = {
> >> +		{ .compatible = "ti,emif-4d" },
> >> +		{ .compatible = "ti,emif-4d5" },
> >> +		{},
> >> +};
> >> +MODULE_DEVICE_TABLE(of, emif_of_match);
> >> +#endif
> >> +
> >>   static struct platform_driver emif_driver = {
> >>   	.remove		= __exit_p(emif_remove),
> >
> > Not part of this patch I realize, but this is a bug.  .remove must
> > be in the __devexit section and the __devexit_p() wrapper must
> > be used.  Similarly, emif_probe must be in the __devinit section.
> 
> Again, in our case remove() is not needed unless the driver is built as
> a module because the devices will never be un-registered. When it is
> built as a module the effect is same for both:

It's just outside the pattern expected for device drivers.  I like to
be careful about things like this.  That's why I recommend __devinit
also, but I see now that the probe hook isn't added to the
platform_device so it isn't required.

> 
> #if defined(MODULE) || defined(CONFIG_HOTPLUG)
> #define __devexit_p(x) x
> #else
> #define __devexit_p(x) NULL
> #endif
> 
> #ifdef MODULE
> #define __exit_p(x) x
> #else
> #define __exit_p(x) NULL
> #endif

Don't go with what is written in the code here; go with what the
meaning of the sections are.  The code can be changed, but the drivers
are expected to honor what the sections mean.

__init can be freed after module init
__devinit in reality never gets freed because devices can show up later
__devexit can be freed if hotplug is not enabled
__exit can be freed after module unload

g.