[PATCH 1/3] Introducing 'gpmc-nand.c' for GPMC specific NAND init
Tony Lindgren
tony at atomide.com
Thu Feb 4 18:47:53 EST 2010
Hi,
Almost there.. Few more comments below.
* Vimal Singh <vimal.newwork at gmail.com> [100112 22:48]:
> From 89eaa5d55e04f65e76ad49ed8b010cba578d91ca Mon Sep 17 00:00:00 2001
> From: Vimal Singh <vimalsingh at ti.com>
> Date: Mon, 11 Jan 2010 16:01:29 +0530
> Subject: [PATCH] Introducing 'gpmc-nand.c' for GPMC specific NAND init
>
> Introducing 'gpmc-nand.c' for GPMC specific NAND init.
> For example: GPMC timing parameters and all.
> This patch also migrates gpmc related calls from 'nand/omap2.c'
> to 'gpmc-nand.c'.
>
> Signed-off-by: Vimal Singh <vimalsingh at ti.com>
> ---
> arch/arm/mach-omap2/Makefile | 3 +
> arch/arm/mach-omap2/gpmc-nand.c | 139 ++++++++++++++++++++++++++++++++
> arch/arm/plat-omap/include/plat/nand.h | 8 ++
> drivers/mtd/nand/omap2.c | 35 +-------
> 4 files changed, 154 insertions(+), 31 deletions(-)
> create mode 100644 arch/arm/mach-omap2/gpmc-nand.c
<snip>
> +static int omap2_nand_gpmc_config(void __iomem *nand_base)
> +{
> + struct gpmc_timings t;
> + int err;
> +
> + memset(&t, 0, sizeof(t));
> + t.sync_clk = gpmc_round_ns_to_ticks(gpmc_nand_data->gpmc_t->sync_clk);
> + t.cs_on = gpmc_round_ns_to_ticks(gpmc_nand_data->gpmc_t->cs_on);
> + t.adv_on = gpmc_round_ns_to_ticks(gpmc_nand_data->gpmc_t->adv_on);
> +
> + /* Read */
> + t.adv_rd_off = gpmc_round_ns_to_ticks(
> + gpmc_nand_data->gpmc_t->adv_rd_off);
> + t.oe_on = t.adv_on;
> + t.access = gpmc_round_ns_to_ticks(gpmc_nand_data->gpmc_t->access);
> + t.oe_off = gpmc_round_ns_to_ticks(gpmc_nand_data->gpmc_t->oe_off);
> + t.cs_rd_off = gpmc_round_ns_to_ticks(gpmc_nand_data->gpmc_t->cs_rd_off);
> + t.rd_cycle = gpmc_round_ns_to_ticks(gpmc_nand_data->gpmc_t->rd_cycle);
> +
> + /* Write */
> + t.adv_wr_off = gpmc_round_ns_to_ticks(
> + gpmc_nand_data->gpmc_t->adv_wr_off);
> + t.we_on = t.oe_on;
> + if (cpu_is_omap34xx()) {
> + t.wr_data_mux_bus = gpmc_round_ns_to_ticks(
> + gpmc_nand_data->gpmc_t->wr_data_mux_bus);
> + t.wr_access = gpmc_round_ns_to_ticks(
> + gpmc_nand_data->gpmc_t->wr_access);
> + }
> + t.we_off = gpmc_round_ns_to_ticks(gpmc_nand_data->gpmc_t->we_off);
> + t.cs_wr_off = gpmc_round_ns_to_ticks(gpmc_nand_data->gpmc_t->cs_wr_off);
> + t.wr_cycle = gpmc_round_ns_to_ticks(gpmc_nand_data->gpmc_t->wr_cycle);
> +
> + /* Configure GPMC */
> + gpmc_cs_write_reg(gpmc_nand_data->cs, GPMC_CS_CONFIG1,
> + GPMC_CONFIG1_DEVICESIZE(gpmc_nand_data->devsize) |
> + GPMC_CONFIG1_DEVICETYPE_NAND);
> +
> + err = gpmc_cs_set_timings(gpmc_nand_data->cs, &t);
> + if (err)
> + return err;
> +
> + return 0;
> +}
The nand_base is unused in omap2_nand_gpmc_config. And it's not needed there,
see below.
Also, maybe rename it to omap2_nand_gpmc_retime() instead? It should get
get called dynamically based on the cpufreq notifications from the driver
whenever the L3 frequency is being scaled. Otherwise NAND will stop working :)
> +
> +static int gpmc_nand_setup(void __iomem *nand_base)
> +{
> + struct device *dev = &gpmc_nand_device.dev;
> +
> + /* Set timings in GPMC */
> + if (omap2_nand_gpmc_config(nand_base) < 0) {
> + dev_err(dev, "Unable to set gpmc timings\n");
> + return -EINVAL;
> + }
> +
> + return 0;
> +}
Here too nand_base is not needed. You can now get rid of this function.
> +
> +int __init gpmc_nand_init(struct omap_nand_platform_data *_nand_data)
> +{
> + unsigned int val;
> + int err = 0;
> + struct device *dev = &gpmc_nand_device.dev;
> +
> + gpmc_nand_data = _nand_data;
> + gpmc_nand_data->nand_setup = gpmc_nand_setup;
> + gpmc_nand_device.dev.platform_data = gpmc_nand_data;
> +
> + err = gpmc_nand_setup(gpmc_nand_data->gpmc_cs_baseaddr);
> + if (err < 0) {
> + dev_err(dev, "NAND platform setup failed: %d\n", err);
> + return err;
> + }
And this ordering must be changed around. You need to first call
gpmc_cs_request to allocate the GPMC area based on the chip select
and size from the gpmc_nand_data.
Only then you can call the timing function.
> + err = gpmc_cs_request(gpmc_nand_data->cs, NAND_IO_SIZE,
> + &gpmc_nand_data->phys_base);
> + if (err < 0) {
> + dev_err(dev, "Cannot request GPMC CS\n");
> + return err;
> + }
So please do the gpmc_cs_request first.
Should be easy to fix for the whole series. Then let's plan on
merging it, it will be a nice improvment for all omaps using
NAND.
Cheers,
Tony
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