Subject: [PATCH 07/29] memory: mvebu-devbus: add Orion5x support

From: [email-masked] (Sebastian Hesselbarth)
Date: Mon, 14 Apr 2014 11:41:31 +0200

On 04/13/2014 04:39 PM, Thomas Petazzoni wrote:
> This commit adds support for the Orion5x family of Marvell processors
> into the mvebu-devbus driver. It differs from the already supported
> Armada 370/XP by:
>
>   * Having a single register (instead of two) for doing all the timing
>     configuration.
>
>   * Having a few less timing configuration parameters.
>
> Signed-off-by: Thomas Petazzoni <[email-masked]>
> ---
>   .../bindings/memory-controllers/mvebu-devbus.txt   | 25 ++++--
>   drivers/memory/mvebu-devbus.c                      | 95 +++++++++++++++++-----
>   2 files changed, 94 insertions(+), 26 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/memory-controllers/mvebu-devbus.txt b/Documentation/devicetree/bindings/memory-controllers/mvebu-devbus.txt
> index 653c90c..aff8e9e 100644
> --- a/Documentation/devicetree/bindings/memory-controllers/mvebu-devbus.txt
> +++ b/Documentation/devicetree/bindings/memory-controllers/mvebu-devbus.txt
> @@ -6,10 +6,11 @@ The actual devices are instantiated from the child nodes of a Device Bus node.
>
>   Required properties:
>
> - - compatible:          Currently only Armada 370/XP SoC are supported,
> -                        with this compatible string:
> + - compatible:          Armada 370/XP SoC are supported using the
> +                        "marvell,mvebu-devbus" compatible string.
>
> -                        marvell,mvebu-devbus
> +                        Orion5x SoC are supported using the
> +                        "marvell,orion-devbus" compatible string.
>
>    - reg:                 A resource specifier for the register space.
>                           This is the base address of a chip select within
> @@ -22,7 +23,7 @@ Required properties:
>                           integer values for each chip-select line in use:
>                           0 <physical address of mapping> <size>
>
> -Mandatory timing properties for child nodes:
> +Timing properties for child nodes:
>
>   Read parameters:
>
> @@ -30,21 +31,26 @@ Read parameters:
>                           drive the AD bus after the completion of a device read.
>                           This prevents contentions on the Device Bus after a read
>                           cycle from a slow device.
> +			Mandatory.
>
> - - devbus,bus-width:    Defines the bus width (e.g. <16>)
> + - devbus,bus-width:    Defines the bus width, in bits (e.g. <16>).
> +   			Mandatory.
>
>    - devbus,badr-skew-ps: Defines the time delay from from A[2:0] toggle,
>                           to read data sample. This parameter is useful for
>                           synchronous pipelined devices, where the address
>                           precedes the read data by one or two cycles.
> +			Mandatory.
>
>    - devbus,acc-first-ps: Defines the time delay from the negation of
>                           ALE[0] to the cycle that the first read data is sampled
>                           by the controller.
> +			Mandatory.
>
>    - devbus,acc-next-ps:  Defines the time delay between the cycle that
>                           samples data N and the cycle that samples data N+1
>                           (in burst accesses).
> +			Mandaory.
>
>    - devbus,rd-setup-ps:  Defines the time delay between DEV_CSn assertion to
>   			DEV_OEn assertion. If set to 0 (default),
> @@ -52,6 +58,8 @@ Read parameters:
>                           This parameter has no affect on <acc-first-ps> parameter
>                           (no affect on first data sample). Set <rd-setup-ps>
>                           to a value smaller than <acc-first-ps>.
> +			Mandatory with "mvebu-devbus" compatible string.
> +			Ignored otherwise.

nit:

Mandatory for "mvebu-devbus" compatible string,
ignored otherwise.

>    - devbus,rd-hold-ps:   Defines the time between the last data sample to the
>   			de-assertion of DEV_CSn. If set to 0 (default),
> @@ -62,16 +70,20 @@ Read parameters:
>                           last data sampled. Also this parameter has no
>                           affect on <turn-off-ps> parameter.
>                           Set <rd-hold-ps> to a value smaller than <turn-off-ps>.
> +			Mandatory with "mvebu-devbus" compatible string.
> +			Ignored otherwise.

ditto.

>
>   Write parameters:
>
>    - devbus,ale-wr-ps:    Defines the time delay from the ALE[0] negation cycle
>   			to the DEV_WEn assertion.
> +			Mandatory.
>
>    - devbus,wr-low-ps:    Defines the time during which DEV_WEn is active.
>                           A[2:0] and Data are kept valid as long as DEV_WEn
>                           is active. This parameter defines the setup time of
>                           address and data to DEV_WEn rise.
> +			Mandatory.
>
>    - devbus,wr-high-ps:   Defines the time during which DEV_WEn is kept
>                           inactive (high) between data beats of a burst write.
> @@ -79,10 +91,13 @@ Write parameters:
>                           <wr-high-ps> - <tick> ps.
>   			This parameter defines the hold time of address and
>   			data after DEV_WEn rise.
> +			Mandatory.
>
>    - devbus,sync-enable: Synchronous device enable.
>                          1: True
>                          0: False
> +		       Mandatory with "mvebu-devbus" compatible string.
> +		       Ignored otherwise.

ditto.

>   An example for an Armada XP GP board, with a 16 MiB NOR device as child
>   is showed below. Note that the Device Bus driver is in charge of allocating
> diff --git a/drivers/memory/mvebu-devbus.c b/drivers/memory/mvebu-devbus.c
> index 8df5b2b..59d8151 100644
> --- a/drivers/memory/mvebu-devbus.c
> +++ b/drivers/memory/mvebu-devbus.c
> @@ -2,7 +2,7 @@
>    * Marvell EBU SoC Device Bus Controller
>    * (memory controller for NOR/NAND/SRAM/FPGA devices)
>    *
> - * Copyright (C) 2013 Marvell
> + * Copyright (C) 2013-2014 Marvell
>    *
>    * This program is free software: you can redistribute it and/or modify
>    * it under the terms of the GNU General Public License as published by
> @@ -44,6 +44,22 @@
>   #define ARMADA_READ_PARAM_OFFSET	0x0
>   #define ARMADA_WRITE_PARAM_OFFSET	0x4
>
> +#define ORION_RESERVED			(0x2 << 30)
> +#define ORION_BADR_SKEW_BIT		28
> +#define ORION_WR_HIGH_EXT_BIT		27
> +#define ORION_WR_LOW_EXT_BIT		26
> +#define ORION_ALE_WR_EXT_BIT		25
> +#define ORION_ACC_NEXT_EXT_BIT		24
> +#define ORION_ACC_FIRST_EXT_BIT		23
> +#define ORION_TURN_OFF_EXT_BIT		22
> +#define ORION_DEV_WIDTH_BIT		20
> +#define ORION_WR_HIGH_BIT		17
> +#define ORION_WR_LOW_BIT		14
> +#define ORION_ALE_WR_BIT		11
> +#define ORION_ACC_NEXT_BIT		7
> +#define ORION_ACC_FIRST_BIT		3
> +#define ORION_TURN_OFF_BIT		0

Same comment about _BIT instead of _SHIFT and not using BIT().

> +
>   struct devbus_read_params {
>   	u32 bus_width;
>   	u32 badr_skew;
> @@ -96,7 +112,6 @@ static int devbus_get_timing_params(struct devbus *devbus,
>   {
>   	int err;
>
> -	/* Get read timings */
>   	err = of_property_read_u32(node, "devbus,bus-width", &r->bus_width);
>   	if (err < 0) {
>   		dev_err(devbus->dev,
> @@ -131,24 +146,25 @@ static int devbus_get_timing_params(struct devbus *devbus,
>   	if (err < 0)
>   		return err;
>
> -	err = get_timing_param_ps(devbus, node, "devbus,rd-setup-ps",
> -				 &r->rd_setup);
> -	if (err < 0)
> -		return err;
> -
> -	err = get_timing_param_ps(devbus, node, "devbus,rd-hold-ps",
> -				 &r->rd_hold);
> -	if (err < 0)
> -		return err;
> -
> -	/* Get write timings */
> -	err = of_property_read_u32(node, "devbus,sync-enable",
> -				  &w->sync_enable);
> -	if (err < 0) {
> -		dev_err(devbus->dev,
> -			"%s has no 'devbus,sync-enable' property\n",
> -			node->full_name);
> -		return err;
> +	if (of_device_is_compatible(devbus->dev->of_node, "marvell,mvebu-devbus")) {
> +		err = get_timing_param_ps(devbus, node, "devbus,rd-setup-ps",
> +					  &r->rd_setup);
> +		if (err < 0)
> +			return err;
> +
> +		err = get_timing_param_ps(devbus, node, "devbus,rd-hold-ps",
> +					  &r->rd_hold);
> +		if (err < 0)
> +			return err;
> +
> +		err = of_property_read_u32(node, "devbus,sync-enable",
> +					   &w->sync_enable);
> +		if (err < 0) {
> +			dev_err(devbus->dev,
> +				"%s has no 'devbus,sync-enable' property\n",
> +				node->full_name);
> +			return err;
> +		}
>   	}
>
>   	err = get_timing_param_ps(devbus, node, "devbus,ale-wr-ps",
> @@ -169,6 +185,39 @@ static int devbus_get_timing_params(struct devbus *devbus,
>   	return 0;
>   }
>
> +static void devbus_orion_set_timing_params(struct devbus *devbus,
> +					  struct device_node *node,
> +					  struct devbus_read_params *r,
> +					  struct devbus_write_params *w)
> +{
> +	u32 value;
> +
> +	/*
> +	 * The hardware designers found it would be a good idea to
> +	 * split most of the values in the register into two fields:
> +	 * one containing all the low-order bits, and another one
> +	 * containing just the high-order bit. For all of those
> +	 * fields, we have to split the value into these two parts.
> +	 */
> +	value = (r->turn_off   & 0x7) << ORION_TURN_OFF_BIT  |
> +		(r->acc_first  & 0xF) << ORION_ACC_FIRST_BIT |
> +		(r->acc_next   & 0xF) << ORION_ACC_NEXT_BIT  |
> +		(w->ale_wr     & 0x7) << ORION_ALE_WR_BIT    |
> +		(w->wr_low     & 0x7) << ORION_WR_LOW_BIT    |
> +		(w->wr_high    & 0x7) << ORION_WR_HIGH_BIT   |
> +		r->bus_width          << ORION_DEV_WIDTH_BIT |
> +		((r->turn_off  & 0x8)  ? BIT(ORION_TURN_OFF_EXT_BIT)  : 0) |
> +		((r->acc_first & 0x10) ? BIT(ORION_ACC_FIRST_EXT_BIT) : 0) |
> +		((r->acc_next  & 0x10) ? BIT(ORION_ACC_NEXT_EXT_BIT)  : 0) |
> +		((w->ale_wr    & 0x8)  ? BIT(ORION_ALE_WR_EXT_BIT)    : 0) |
> +		((w->wr_low    & 0x8)  ? BIT(ORION_WR_LOW_EXT_BIT)    : 0) |
> +		((w->wr_high   & 0x8)  ? BIT(ORION_WR_HIGH_EXT_BIT)   : 0) |

I know you will scream in pain, but there should be _MASK for the magic
numbers above :P

> +		(r->badr_skew << ORION_BADR_SKEW_BIT) |
> +		ORION_RESERVED;
> +
> +	writel(value, devbus->base);
> +}
> +
>   static void devbus_armada_set_timing_params(struct devbus *devbus,
>   					   struct device_node *node,
>   					   struct devbus_read_params *r,
> @@ -248,7 +297,10 @@ static int mvebu_devbus_probe(struct platform_device *pdev)
>   		return err;
>
>   	/* Set the new timing parameters */
> -	devbus_armada_set_timing_params(devbus, node, &r, &w);
> +	if (of_device_is_compatible(node, "marvell,orion-devbus"))
> +		devbus_orion_set_timing_params(devbus, node, &r, &w);
> +	else
> +		devbus_armada_set_timing_params(devbus, node, &r, &w);
>
>   	/*
>   	 * We need to create a child device explicitly from here to
> @@ -264,6 +316,7 @@ static int mvebu_devbus_probe(struct platform_device *pdev)
>
>   static const struct of_device_id mvebu_devbus_of_match[] = {
>   	{ .compatible = "marvell,mvebu-devbus" },
> +	{ .compatible = "marvell,orion-devbus" },
>   	{},
>   };
>   MODULE_DEVICE_TABLE(of, mvebu_devbus_of_match);
>