Adding upstream version 4.19.249.upstream/4.19.249upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 96 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/mtd/mtd-physmap.txt b/Documentation/devicetree/bindings/mtd/mtd-physmap.txt
new file mode 100644
index 000000000..232fa12e9
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+++ b/Documentation/devicetree/bindings/mtd/mtd-physmap.txt
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+CFI or JEDEC memory-mapped NOR flash, MTD-RAM (NVRAM...)
+
+Flash chips (Memory Technology Devices) are often used for solid state
+file systems on embedded devices.
+
+ - compatible : should contain the specific model of mtd chip(s)
+   used, if known, followed by either "cfi-flash", "jedec-flash",
+   "mtd-ram" or "mtd-rom".
+ - reg : Address range(s) of the mtd chip(s)
+   It's possible to (optionally) define multiple "reg" tuples so that
+   non-identical chips can be described in one node.
+ - bank-width : Width (in bytes) of the bank.  Equal to the
+   device width times the number of interleaved chips.
+ - device-width : (optional) Width of a single mtd chip.  If
+   omitted, assumed to be equal to 'bank-width'.
+ - #address-cells, #size-cells : Must be present if the device has
+   sub-nodes representing partitions (see below).  In this case
+   both #address-cells and #size-cells must be equal to 1.
+ - no-unaligned-direct-access: boolean to disable the default direct
+   mapping of the flash.
+   On some platforms (e.g. MPC5200) a direct 1:1 mapping may cause
+   problems with JFFS2 usage, as the local bus (LPB) doesn't support
+   unaligned accesses as implemented in the JFFS2 code via memcpy().
+   By defining "no-unaligned-direct-access", the flash will not be
+   exposed directly to the MTD users (e.g. JFFS2) any more.
+ - linux,mtd-name: allow to specify the mtd name for retro capability with
+   physmap-flash drivers as boot loader pass the mtd partition via the old
+   device name physmap-flash.
+ - use-advanced-sector-protection: boolean to enable support for the
+   advanced sector protection (Spansion: PPB - Persistent Protection
+   Bits) locking.
+
+For JEDEC compatible devices, the following additional properties
+are defined:
+
+ - vendor-id : Contains the flash chip's vendor id (1 byte).
+ - device-id : Contains the flash chip's device id (1 byte).
+
+For ROM compatible devices (and ROM fallback from cfi-flash), the following
+additional (optional) property is defined:
+
+ - erase-size : The chip's physical erase block size in bytes.
+
+ The device tree may optionally contain endianness property.
+ little-endian or big-endian : It Represents the endianness that should be used
+                               by the controller to  properly read/write data
+			       from/to the flash. If this property is missing,
+			       the endianness is chosen by the system
+			       (potentially based on extra configuration options).
+
+The device tree may optionally contain sub-nodes describing partitions of the
+address space. See partition.txt for more detail.
+
+Example:
+
+	flash@ff000000 {
+		compatible = "amd,am29lv128ml", "cfi-flash";
+		reg = <ff000000 01000000>;
+		bank-width = <4>;
+		device-width = <1>;
+		#address-cells = <1>;
+		#size-cells = <1>;
+		fs@0 {
+			label = "fs";
+			reg = <0 f80000>;
+		};
+		firmware@f80000 {
+			label ="firmware";
+			reg = <f80000 80000>;
+			read-only;
+		};
+	};
+
+Here an example with multiple "reg" tuples:
+
+	flash@f0000000,0 {
+		#address-cells = <1>;
+		#size-cells = <1>;
+		compatible = "intel,PC48F4400P0VB", "cfi-flash";
+		reg = <0 0x00000000 0x02000000
+		       0 0x02000000 0x02000000>;
+		bank-width = <2>;
+		partition@0 {
+			label = "test-part1";
+			reg = <0 0x04000000>;
+		};
+	};
+
+An example using SRAM:
+
+	sram@2,0 {
+		compatible = "samsung,k6f1616u6a", "mtd-ram";
+		reg = <2 0 0x00200000>;
+		bank-width = <2>;
+	};
+