mtd: at91: add dt parameters for Atmel PMECC
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linux-mtd at lists.infradead.org
Fri Jul 6 13:59:07 EDT 2012
Gitweb: http://git.infradead.org/?p=mtd-2.6.git;a=commit;h=a41b51a1f7c15a1b00f30a3ad2d0373ad51b883d
Commit: a41b51a1f7c15a1b00f30a3ad2d0373ad51b883d
Parent: fae255253b393d5e4f0d77d5afa103bfc8b47a97
Author: Josh Wu <josh.wu at atmel.com>
AuthorDate: Fri Jun 29 17:47:54 2012 +0800
Committer: David Woodhouse <David.Woodhouse at intel.com>
CommitDate: Fri Jul 6 18:21:09 2012 +0100
mtd: at91: add dt parameters for Atmel PMECC
Add DT support for PMECC parameters.
Signed-off-by: Hong Xu <hong.xu at atmel.com>
Signed-off-by: Josh Wu <josh.wu at atmel.com>
Acked-by: Nicolas Ferre <nicolas.ferre at atmel.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy at linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse at intel.com>
---
.../devicetree/bindings/mtd/atmel-nand.txt | 40 +++++++++++++++-
drivers/mtd/nand/atmel_nand.c | 52 +++++++++++++++++++-
2 files changed, 90 insertions(+), 2 deletions(-)
diff --git a/Documentation/devicetree/bindings/mtd/atmel-nand.txt b/Documentation/devicetree/bindings/mtd/atmel-nand.txt
index a200695..d555421 100644
--- a/Documentation/devicetree/bindings/mtd/atmel-nand.txt
+++ b/Documentation/devicetree/bindings/mtd/atmel-nand.txt
@@ -3,7 +3,9 @@ Atmel NAND flash
Required properties:
- compatible : "atmel,at91rm9200-nand".
- reg : should specify localbus address and size used for the chip,
- and if availlable the ECC.
+ and hardware ECC controller if available.
+ If the hardware ECC is PMECC, it should contain address and size for
+ PMECC, PMECC Error Location controller and ROM which has lookup tables.
- atmel,nand-addr-offset : offset for the address latch.
- atmel,nand-cmd-offset : offset for the command latch.
- #address-cells, #size-cells : Must be present if the device has sub-nodes
@@ -16,6 +18,15 @@ Optional properties:
- nand-ecc-mode : String, operation mode of the NAND ecc mode, soft by default.
Supported values are: "none", "soft", "hw", "hw_syndrome", "hw_oob_first",
"soft_bch".
+- atmel,has-pmecc : boolean to enable Programmable Multibit ECC hardware.
+ Only supported by at91sam9x5 or later sam9 product.
+- atmel,pmecc-cap : error correct capability for Programmable Multibit ECC
+ Controller. Supported values are: 2, 4, 8, 12, 24.
+- atmel,pmecc-sector-size : sector size for ECC computation. Supported values
+ are: 512, 1024.
+- atmel,pmecc-lookup-table-offset : includes two offsets of lookup table in ROM
+ for different sector size. First one is for sector size 512, the next is for
+ sector size 1024.
- nand-bus-width : 8 or 16 bus width if not present 8
- nand-on-flash-bbt: boolean to enable on flash bbt option if not present false
@@ -39,3 +50,30 @@ nand0: nand at 40000000,0 {
...
};
};
+
+/* for PMECC supported chips */
+nand0: nand at 40000000 {
+ compatible = "atmel,at91rm9200-nand";
+ #address-cells = <1>;
+ #size-cells = <1>;
+ reg = < 0x40000000 0x10000000 /* bus addr & size */
+ 0xffffe000 0x00000600 /* PMECC addr & size */
+ 0xffffe600 0x00000200 /* PMECC ERRLOC addr & size */
+ 0x00100000 0x00100000 /* ROM addr & size */
+ >;
+ atmel,nand-addr-offset = <21>; /* ale */
+ atmel,nand-cmd-offset = <22>; /* cle */
+ nand-on-flash-bbt;
+ nand-ecc-mode = "hw";
+ atmel,has-pmecc; /* enable PMECC */
+ atmel,pmecc-cap = <2>;
+ atmel,pmecc-sector-size = <512>;
+ atmel,pmecc-lookup-table-offset = <0x8000 0x10000>;
+ gpios = <&pioD 5 0 /* rdy */
+ &pioD 4 0 /* nce */
+ 0 /* cd */
+ >;
+ partition at 0 {
+ ...
+ };
+};
diff --git a/drivers/mtd/nand/atmel_nand.c b/drivers/mtd/nand/atmel_nand.c
index 7a41a04..b97ad9f 100644
--- a/drivers/mtd/nand/atmel_nand.c
+++ b/drivers/mtd/nand/atmel_nand.c
@@ -93,6 +93,11 @@ struct atmel_nand_host {
struct completion comp;
struct dma_chan *dma_chan;
+
+ bool has_pmecc;
+ u8 pmecc_corr_cap;
+ u16 pmecc_sector_size;
+ u32 pmecc_lookup_table_offset;
};
static int cpu_has_dma(void)
@@ -481,7 +486,8 @@ static void atmel_nand_hwctl(struct mtd_info *mtd, int mode)
static int __devinit atmel_of_init_port(struct atmel_nand_host *host,
struct device_node *np)
{
- u32 val;
+ u32 val, table_offset;
+ u32 offset[2];
int ecc_mode;
struct atmel_nand_data *board = &host->board;
enum of_gpio_flags flags;
@@ -517,6 +523,50 @@ static int __devinit atmel_of_init_port(struct atmel_nand_host *host,
board->enable_pin = of_get_gpio(np, 1);
board->det_pin = of_get_gpio(np, 2);
+ host->has_pmecc = of_property_read_bool(np, "atmel,has-pmecc");
+
+ if (!(board->ecc_mode == NAND_ECC_HW) || !host->has_pmecc)
+ return 0; /* Not using PMECC */
+
+ /* use PMECC, get correction capability, sector size and lookup
+ * table offset.
+ */
+ if (of_property_read_u32(np, "atmel,pmecc-cap", &val) != 0) {
+ dev_err(host->dev, "Cannot decide PMECC Capability\n");
+ return -EINVAL;
+ } else if ((val != 2) && (val != 4) && (val != 8) && (val != 12) &&
+ (val != 24)) {
+ dev_err(host->dev,
+ "Unsupported PMECC correction capability: %d; should be 2, 4, 8, 12 or 24\n",
+ val);
+ return -EINVAL;
+ }
+ host->pmecc_corr_cap = (u8)val;
+
+ if (of_property_read_u32(np, "atmel,pmecc-sector-size", &val) != 0) {
+ dev_err(host->dev, "Cannot decide PMECC Sector Size\n");
+ return -EINVAL;
+ } else if ((val != 512) && (val != 1024)) {
+ dev_err(host->dev,
+ "Unsupported PMECC sector size: %d; should be 512 or 1024 bytes\n",
+ val);
+ return -EINVAL;
+ }
+ host->pmecc_sector_size = (u16)val;
+
+ if (of_property_read_u32_array(np, "atmel,pmecc-lookup-table-offset",
+ offset, 2) != 0) {
+ dev_err(host->dev, "Cannot get PMECC lookup table offset\n");
+ return -EINVAL;
+ }
+ table_offset = host->pmecc_sector_size == 512 ? offset[0] : offset[1];
+
+ if (!table_offset) {
+ dev_err(host->dev, "Invalid PMECC lookup table offset\n");
+ return -EINVAL;
+ }
+ host->pmecc_lookup_table_offset = table_offset;
+
return 0;
}
#else
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