qcom: Add SMEM MTD parser

QCOM platforms such as IPQ806x are using SMEM to store their flash layout. This patch set adds the DT nodes required to instanciate SMEM on IPQ806x and add an MTD parser using it.

This change is based on the SMEM driver posted here:
*https://lkml.org/lkml/2015/7/27/1125

v2:
*Release the SPI device reference after looking it up (put_device()) *Represent SMEM data as __le32 rather than u32
*Move new DT nodes in their proper respective location *Address readability concerns in MTD parser

v3:
*Address Bjorn's comments

Mathieu Olivari (3):
ARM: qcom: add SFPB nodes to IPQ806x dts
ARM: qcom: add SMEM device node to IPQ806x dts
mtd: add SMEM parser for QCOM platforms

 arch/arm/boot/dts/qcom-ipq8064.dtsi |  23 +++-
 drivers/mtd/Kconfig                 |   7 ++
 drivers/mtd/Makefile                |   1 +
 drivers/mtd/qcom_smem_part.c        | 224 ++++++++++++++++++++++++++++++++++++
 4 files changed, 254 insertions(+), 1 deletion(-)
 create mode 100644 drivers/mtd/qcom_smem_part.c

2.1.4

Add one new node to the ipq806x.dtsi file to declare & register the hardware spinlock devices. This mechanism is required to be used by other drivers such as SMEM.

---
 arch/arm/boot/dts/qcom-ipq8064.dtsi | 11 +++++++++++
 1 file changed, 11 insertions(+)

index 9f727d8..8d366ae 100644
@@ -329,5 +329,16 @@
 			#reset-cells = <1>;
 		};
 
+		sfpb_mutex_block: syscon at 1200600 {
+			compatible = "syscon";
+			reg = <0x01200600 0x100>;
+		};
+	};
+
+	sfpb_mutex: sfpb-mutex {
+		compatible = "qcom,sfpb-mutex";
+		syscon = <&sfpb_mutex_block 4 4>;
+
+		#hwlock-cells = <1>;
 	};
 };

2.1.4

SMEM is used on IPQ806x to store various board related information such as boot device and flash partition layout. We'll declare it as a device so we can make use of it thanks to the new SMEM soc driver.

---
 arch/arm/boot/dts/qcom-ipq8064.dtsi | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

index 8d366ae..85dbccf 100644
@@ -55,7 +55,7 @@
 			no-map;
 		};
 
-		smem at 41000000 {
+		smem: smem at 41000000 {
 			reg = <0x41000000 0x200000>;
 			no-map;
 		};

@@ -341,4 +341,10 @@
 
 		#hwlock-cells = <1>;
 	};
+
+	smem {
+		compatible = "qcom,smem";
+		memory-region = <&smem>;
+		hwlocks = <&sfpb_mutex 3>;
+	};
 };

2.1.4

On QCOM platforms using MTD devices storage (such as IPQ806x), SMEM is used to store partition layout. This new parser can now be used to read SMEM and use it to register an MTD layout according to its content.

---

Notes:
v2:
*Release the SPI device reference after looking it up (put_device()) *Represent SMEM data as __le32 rather than u32
*Move new DT nodes in their proper respective location *Address readability concerns in MTD parser

v3:
*Redefine SMEM functions prototypes for better readability *Duplicate MTD name instead of pointing to SMEM string location in case
mtd layer tries to free it
*Rework some of the comments

 drivers/mtd/Kconfig          |   7 ++
 drivers/mtd/Makefile         |   1 +
 drivers/mtd/qcom_smem_part.c | 246 +++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 254 insertions(+)
 create mode 100644 drivers/mtd/qcom_smem_part.c

index a03ad29..debc887 100644
@@ -155,6 +155,13 @@ config MTD_BCM47XX_PARTS
 	  This provides partitions parser for devices based on BCM47xx
 	  boards.
 
+config MTD_QCOM_SMEM_PARTS
+	tristate "QCOM SMEM partitioning support"
+	depends on QCOM_SMEM
+	help
+	  This provides partitions parser for QCOM devices using SMEM
+	  such as IPQ806x.
+
 comment "User Modules And Translation Layers"
 
 #

index 99bb9a1..b3c7de4 100644
@@ -13,6 +13,7 @@ obj-$(CONFIG_MTD_AFS_PARTS)	+= afs.o
 obj-$(CONFIG_MTD_AR7_PARTS)	+= ar7part.o
 obj-$(CONFIG_MTD_BCM63XX_PARTS)	+= bcm63xxpart.o
 obj-$(CONFIG_MTD_BCM47XX_PARTS)	+= bcm47xxpart.o
+obj-$(CONFIG_MTD_QCOM_SMEM_PARTS) += qcom_smem_part.o
 
 # 'Users' - code which presents functionality to userspace.
 obj-$(CONFIG_MTD_BLKDEVS)	+= mtd_blkdevs.o

2.1.4

Looks good, but the license string should be "GPL v2" (lower case v). Just as a hint...I made checkpatch warn you about that a while back ;)

The rest is

[..]

Hi,

Nice work. After testing it on AP148 I see this:

[    2.481507] 12 qcom-smem partitions found on MTD device qcom-nandc
[    2.481540] Creating 12 MTD partitions on "qcom-nandc":
[    2.486690] 0x000000000000-0x000000040000 : "0:SBL1"
[    2.492842] 0x000000040000-0x000000180000 : "0:MIBIB"
[    2.497857] 0x000000180000-0x0000002c0000 : "0:SBL2"
[    2.502895] 0x0000002c0000-0x000000540000 : "0:SBL3"
[    2.507828] 0x000000540000-0x000000660000 : "0:DDRCONFIG"
[    2.512857] 0x000000660000-0x000000780000 : "0:SSD"
[    2.518074] 0x000000780000-0x000000a00000 : "0:TZ"
[    2.522834] 0x000000a00000-0x000000c80000 : "0:RPM"
[    2.527607] 0x000000c80000-0x000001180000 : "0:APPSBL"
[    2.532472] 0x000001180000-0x000001200000 : "0:APPSBLENV"
[    2.537586] 0x000001200000-0x000001340000 : "0:ART"
[    2.543140] 0x000001340000-0x000005340000 : "rootfs"

Are all these partition names supposed to be prefixed with "0:"? This is using the OpenWrt applied version.

Jonas

Yes. These are the names as they are listed in SMEM. If you run the "smem" command from the U-boot prompt, you will see the same information. I'm not sure what the 0: prefix means, and where it comes from to be honest.