From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail-wi0-x22a.google.com ([2a00:1450:400c:c05::22a]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1ZkIc1-0002Hh-9u for barebox@lists.infradead.org; Thu, 08 Oct 2015 21:20:30 +0000 Received: by wicgb1 with SMTP id gb1so43131461wic.1 for ; Thu, 08 Oct 2015 14:20:07 -0700 (PDT) From: Sebastian Hesselbarth Date: Thu, 8 Oct 2015 23:20:01 +0200 Message-Id: <1444339201-17552-1-git-send-email-sebastian.hesselbarth@gmail.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "barebox" Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: [PATCH] clk: mvebu: Add corediv clock driver for Armada 370/XP To: Sebastian Hesselbarth Cc: Thomas Petazzoni , barebox@lists.infradead.org, Ezequiel Garcia Newer Marvell MVEBU SoC like Armada 370/XP have an additional core clock divider for e.g. NAND clock. Add the corresponding driver based on the Linux driver. Signed-off-by: Sebastian Hesselbarth --- Cc: Thomas Petazzoni Cc: Ezequiel Garcia Cc: barebox@lists.infradead.org --- drivers/clk/mvebu/Makefile | 4 +- drivers/clk/mvebu/corediv.c | 262 ++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 264 insertions(+), 2 deletions(-) create mode 100644 drivers/clk/mvebu/corediv.c diff --git a/drivers/clk/mvebu/Makefile b/drivers/clk/mvebu/Makefile index 6255a5f56d6b..4b2c3c84311b 100644 --- a/drivers/clk/mvebu/Makefile +++ b/drivers/clk/mvebu/Makefile @@ -1,5 +1,5 @@ obj-y += common.o -obj-$(CONFIG_ARCH_ARMADA_370) += armada-370.o -obj-$(CONFIG_ARCH_ARMADA_XP) += armada-xp.o +obj-$(CONFIG_ARCH_ARMADA_370) += armada-370.o corediv.o +obj-$(CONFIG_ARCH_ARMADA_XP) += armada-xp.o corediv.o obj-$(CONFIG_ARCH_DOVE) += dove.o obj-$(CONFIG_ARCH_KIRKWOOD) += kirkwood.o diff --git a/drivers/clk/mvebu/corediv.c b/drivers/clk/mvebu/corediv.c new file mode 100644 index 000000000000..55f6e6ad62e8 --- /dev/null +++ b/drivers/clk/mvebu/corediv.c @@ -0,0 +1,262 @@ +/* + * MVEBU Core divider clock + * + * Sebastian Hesselbarth + * + * Based on Linux driver + * Copyright (C) 2013 Marvell + * Ezequiel Garcia + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ + +#include +#include +#include +#include +#include +#include +#include + +/* + * This structure describes the hardware details (bit offset and mask) + * to configure one particular core divider clock. Those hardware + * details may differ from one SoC to another. This structure is + * therefore typically instantiated statically to describe the + * hardware details. + */ +struct clk_corediv_desc { + unsigned int mask; + unsigned int offset; + unsigned int fieldbit; +}; + +/* + * This structure describes the hardware details to configure the core + * divider clocks on a given SoC. Amongst others, it points to the + * array of core divider clock descriptors for this SoC, as well as + * the corresponding operations to manipulate them. + */ +struct clk_corediv_soc_desc { + const struct clk_corediv_desc *descs; + unsigned int ndescs; + const struct clk_ops ops; + u32 ratio_reload; + u32 enable_bit_offset; + u32 ratio_offset; +}; + +/* + * This structure represents one core divider clock for the clock + * framework, and is dynamically allocated for each core divider clock + * existing in the current SoC. + */ +struct clk_corediv { + struct clk clk; + void __iomem *reg; + const struct clk_corediv_desc *desc; + const struct clk_corediv_soc_desc *soc_desc; +}; + +static struct clk_onecell_data clk_data; + +/* + * Description of the core divider clocks available. For now, we + * support only NAND, and it is available at the same register + * locations regardless of the SoC. + */ +static const struct clk_corediv_desc mvebu_corediv_desc[] = { + { .mask = 0x3f, .offset = 8, .fieldbit = 1 }, /* NAND clock */ +}; + +#define CORE_CLK_DIV_RATIO_MASK 0xff + +#define to_corediv_clk(p) container_of(p, struct clk_corediv, clk) + +static int clk_corediv_is_enabled(struct clk *clk) +{ + struct clk_corediv *corediv = to_corediv_clk(clk); + const struct clk_corediv_soc_desc *soc_desc = corediv->soc_desc; + const struct clk_corediv_desc *desc = corediv->desc; + u32 enable_mask = BIT(desc->fieldbit) << soc_desc->enable_bit_offset; + + return !!(readl(corediv->reg) & enable_mask); +} + +static int clk_corediv_enable(struct clk *clk) +{ + struct clk_corediv *corediv = to_corediv_clk(clk); + const struct clk_corediv_soc_desc *soc_desc = corediv->soc_desc; + const struct clk_corediv_desc *desc = corediv->desc; + u32 reg; + + reg = readl(corediv->reg); + reg |= (BIT(desc->fieldbit) << soc_desc->enable_bit_offset); + writel(reg, corediv->reg); + + return 0; +} + +static void clk_corediv_disable(struct clk *clk) +{ + struct clk_corediv *corediv = to_corediv_clk(clk); + const struct clk_corediv_soc_desc *soc_desc = corediv->soc_desc; + const struct clk_corediv_desc *desc = corediv->desc; + u32 reg; + + reg = readl(corediv->reg); + reg &= ~(BIT(desc->fieldbit) << soc_desc->enable_bit_offset); + writel(reg, corediv->reg); +} + +static unsigned long clk_corediv_recalc_rate(struct clk *clk, + unsigned long parent_rate) +{ + struct clk_corediv *corediv = to_corediv_clk(clk); + const struct clk_corediv_soc_desc *soc_desc = corediv->soc_desc; + const struct clk_corediv_desc *desc = corediv->desc; + u32 reg, div; + + reg = readl(corediv->reg + soc_desc->ratio_offset); + div = (reg >> desc->offset) & desc->mask; + return parent_rate / div; +} + +static long clk_corediv_round_rate(struct clk *clk, unsigned long rate, + unsigned long *parent_rate) +{ + /* Valid ratio are 1:4, 1:5, 1:6 and 1:8 */ + u32 div; + + div = *parent_rate / rate; + if (div < 4) + div = 4; + else if (div > 6) + div = 8; + + return *parent_rate / div; +} + +static int clk_corediv_set_rate(struct clk *clk, unsigned long rate, + unsigned long parent_rate) +{ + struct clk_corediv *corediv = to_corediv_clk(clk); + const struct clk_corediv_soc_desc *soc_desc = corediv->soc_desc; + const struct clk_corediv_desc *desc = corediv->desc; + u32 reg, div; + + div = parent_rate / rate; + + /* Write new divider to the divider ratio register */ + reg = readl(corediv->reg + soc_desc->ratio_offset); + reg &= ~(desc->mask << desc->offset); + reg |= (div & desc->mask) << desc->offset; + writel(reg, corediv->reg + soc_desc->ratio_offset); + + /* Set reload-force for this clock */ + reg = readl(corediv->reg) | BIT(desc->fieldbit); + writel(reg, corediv->reg); + + /* Now trigger the clock update */ + reg = readl(corediv->reg) | soc_desc->ratio_reload; + writel(reg, corediv->reg); + + /* + * Wait for clocks to settle down, and then clear all the + * ratios request and the reload request. + */ + udelay(1000); + reg &= ~(CORE_CLK_DIV_RATIO_MASK | soc_desc->ratio_reload); + writel(reg, corediv->reg); + udelay(1000); + + return 0; +} + +static const struct clk_corediv_soc_desc armada370_corediv_soc = { + .descs = mvebu_corediv_desc, + .ndescs = ARRAY_SIZE(mvebu_corediv_desc), + .ops = { + .enable = clk_corediv_enable, + .disable = clk_corediv_disable, + .is_enabled = clk_corediv_is_enabled, + .recalc_rate = clk_corediv_recalc_rate, + .round_rate = clk_corediv_round_rate, + .set_rate = clk_corediv_set_rate, + }, + .ratio_reload = BIT(8), + .enable_bit_offset = 24, + .ratio_offset = 0x8, +}; + +static struct of_device_id mvebu_corediv_clk_ids[] = { + { .compatible = "marvell,armada-370-corediv-clock", + .data = &armada370_corediv_soc }, + { } +}; + +static int mvebu_corediv_clk_probe(struct device_d *dev) +{ + struct device_node *np = dev->device_node; + const struct of_device_id *match; + const struct clk_corediv_soc_desc *soc_desc; + struct clk_corediv *corediv; + struct clk *parent; + void __iomem *base; + int n; + + match = of_match_node(mvebu_corediv_clk_ids, np); + if (!match) + return -EINVAL; + soc_desc = (const struct clk_corediv_soc_desc *)match->data; + + base = dev_request_mem_region(dev, 0); + if (IS_ERR(base)) + return PTR_ERR(base); + + parent = of_clk_get(np, 0); + if (IS_ERR(parent)) + return PTR_ERR(parent); + + clk_data.clk_num = soc_desc->ndescs; + clk_data.clks = xzalloc(clk_data.clk_num * sizeof(*clk_data.clks)); + corediv = xzalloc(clk_data.clk_num * sizeof(*corediv)); + + for (n = 0; n < clk_data.clk_num; n++) { + const char *clk_name; + struct clk *clk = &corediv->clk; + + if (of_property_read_string_index(np, + "clock-output-names", n, &clk_name)) { + dev_warn(dev, "missing clock output name %d\n", n); + continue; + } + + clk->ops = &soc_desc->ops; + clk->name = clk_name; + clk->flags = 0; + clk->parent_names = &parent->name; + clk->num_parents = 1; + corediv->soc_desc = soc_desc; + corediv->desc = &soc_desc->descs[n]; + corediv->reg = base; + clk_data.clks[n] = clk; + WARN_ON(IS_ERR_VALUE(clk_register(clk))); + } + + return of_clk_add_provider(np, of_clk_src_onecell_get, &clk_data); +} + +static struct driver_d mvebu_corediv_clk_driver = { + .probe = mvebu_corediv_clk_probe, + .name = "mvebu-corediv-clk", + .of_compatible = DRV_OF_COMPAT(mvebu_corediv_clk_ids), +}; + +static int mvebu_corediv_clk_init(void) +{ + return platform_driver_register(&mvebu_corediv_clk_driver); +} +postcore_initcall(mvebu_corediv_clk_init); -- 2.1.0 _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox