The NAND flash on the TQM8548_BE modules requires a short delay after
running the UPM pattern. The TQM8548_BE requires a further short delay
after writing out a buffer. Normally the R/B pin should be checked, but
it's not connected on the TQM8548_BE. The existing driver uses similar
fixed delay points. To manage these extra delays in a more general way,
I introduced the "fsl,ump-wait-flags" property allowing the board-
specific driver to specify various types of extra delay.

Signed-off-by: Wolfgang Grandegger <w...@grandegger.com>
---
 drivers/mtd/nand/fsl_upm.c |   20 ++++++++++++++++++--
 1 file changed, 18 insertions(+), 2 deletions(-)

Index: linux-2.6/drivers/mtd/nand/fsl_upm.c
===================================================================
--- linux-2.6.orig/drivers/mtd/nand/fsl_upm.c   2009-03-30 12:01:35.634720440 
+0200
+++ linux-2.6/drivers/mtd/nand/fsl_upm.c        2009-03-30 12:01:38.918718552 
+0200
@@ -23,6 +23,10 @@
 #include <linux/io.h>
 #include <asm/fsl_lbc.h>
 
+#define FSL_UPM_WAIT_RUN_PATTERN  0x1
+#define FSL_UPM_WAIT_WRITE_BYTE   0x2
+#define FSL_UPM_WAIT_WRITE_BUFFER 0x4
+
 struct fsl_upm_nand {
        struct device *dev;
        struct mtd_info mtd;
@@ -41,6 +45,7 @@
        uint32_t mchip_count;
        uint32_t mchip_number;
        int chip_delay;
+       uint32_t wait_flags;
 };
 
 #define to_fsl_upm_nand(mtd) container_of(mtd, struct fsl_upm_nand, mtd)
@@ -96,7 +101,8 @@
                fun->mchip_offsets[fun->mchip_number];
        fsl_upm_run_pattern(&fun->upm, chip->IO_ADDR_R, mar);
 
-       fun_wait_rnb(fun);
+       if (fun->wait_flags & FSL_UPM_WAIT_RUN_PATTERN)
+               fun_wait_rnb(fun);
 }
 
 static void fun_select_chip(struct mtd_info *mtd, int mchip_nr)
@@ -138,8 +144,11 @@
 
        for (i = 0; i < len; i++) {
                out_8(fun->chip.IO_ADDR_W, buf[i]);
-               fun_wait_rnb(fun);
+               if (fun->wait_flags & FSL_UPM_WAIT_WRITE_BYTE)
+                       fun_wait_rnb(fun);
        }
+       if (fun->wait_flags & FSL_UPM_WAIT_WRITE_BUFFER)
+               fun_wait_rnb(fun);
 }
 
 static int __devinit fun_chip_init(struct fsl_upm_nand *fun,
@@ -285,6 +294,13 @@
        else
                fun->chip_delay = 50;
 
+       prop = of_get_property(ofdev->node, "fsl,upm-wait-flags", &size);
+       if (prop && size == sizeof(uint32_t))
+               fun->wait_flags = *prop;
+       else
+               fun->wait_flags = FSL_UPM_WAIT_RUN_PATTERN |
+                                 FSL_UPM_WAIT_WRITE_BYTE;
+
        fun->io_base = devm_ioremap_nocache(&ofdev->dev, io_res.start,
                                            io_res.end - io_res.start + 1);
        if (!fun->io_base) {

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