linux/drivers/clk/imx/clk-composite-8m.c

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// SPDX-License-Identifier: GPL-2.0
/*
* Copyright 2018 NXP
*/
clk: Remove io.h from clk-provider.h Now that we've gotten rid of clk_readl() we can remove io.h from the clk-provider header and push out the io.h include to any code that isn't already including the io.h header but using things like readl/writel, etc. Found with this grep: git grep -l clk-provider.h | grep '.c$' | xargs git grep -L 'linux/io.h' | \ xargs git grep -l \ -e '\<__iowrite32_copy\>' --or \ -e '\<__ioread32_copy\>' --or \ -e '\<__iowrite64_copy\>' --or \ -e '\<ioremap_page_range\>' --or \ -e '\<ioremap_huge_init\>' --or \ -e '\<arch_ioremap_pud_supported\>' --or \ -e '\<arch_ioremap_pmd_supported\>' --or \ -e '\<devm_ioport_map\>' --or \ -e '\<devm_ioport_unmap\>' --or \ -e '\<IOMEM_ERR_PTR\>' --or \ -e '\<devm_ioremap\>' --or \ -e '\<devm_ioremap_nocache\>' --or \ -e '\<devm_ioremap_wc\>' --or \ -e '\<devm_iounmap\>' --or \ -e '\<devm_ioremap_release\>' --or \ -e '\<devm_memremap\>' --or \ -e '\<devm_memunmap\>' --or \ -e '\<__devm_memremap_pages\>' --or \ -e '\<pci_remap_cfgspace\>' --or \ -e '\<arch_has_dev_port\>' --or \ -e '\<arch_phys_wc_add\>' --or \ -e '\<arch_phys_wc_del\>' --or \ -e '\<memremap\>' --or \ -e '\<memunmap\>' --or \ -e '\<arch_io_reserve_memtype_wc\>' --or \ -e '\<arch_io_free_memtype_wc\>' --or \ -e '\<__io_aw\>' --or \ -e '\<__io_pbw\>' --or \ -e '\<__io_paw\>' --or \ -e '\<__io_pbr\>' --or \ -e '\<__io_par\>' --or \ -e '\<__raw_readb\>' --or \ -e '\<__raw_readw\>' --or \ -e '\<__raw_readl\>' --or \ -e '\<__raw_readq\>' --or \ -e '\<__raw_writeb\>' --or \ -e '\<__raw_writew\>' --or \ -e '\<__raw_writel\>' --or \ -e '\<__raw_writeq\>' --or \ -e '\<readb\>' --or \ -e '\<readw\>' --or \ -e '\<readl\>' --or \ -e '\<readq\>' --or \ -e '\<writeb\>' --or \ -e '\<writew\>' --or \ -e '\<writel\>' --or \ -e '\<writeq\>' --or \ -e '\<readb_relaxed\>' --or \ -e '\<readw_relaxed\>' --or \ -e '\<readl_relaxed\>' --or \ -e '\<readq_relaxed\>' --or \ -e '\<writeb_relaxed\>' --or \ -e '\<writew_relaxed\>' --or \ -e '\<writel_relaxed\>' --or \ -e '\<writeq_relaxed\>' --or \ -e '\<readsb\>' --or \ -e '\<readsw\>' --or \ -e '\<readsl\>' --or \ -e '\<readsq\>' --or \ -e '\<writesb\>' --or \ -e '\<writesw\>' --or \ -e '\<writesl\>' --or \ -e '\<writesq\>' --or \ -e '\<inb\>' --or \ -e '\<inw\>' --or \ -e '\<inl\>' --or \ -e '\<outb\>' --or \ -e '\<outw\>' --or \ -e '\<outl\>' --or \ -e '\<inb_p\>' --or \ -e '\<inw_p\>' --or \ -e '\<inl_p\>' --or \ -e '\<outb_p\>' --or \ -e '\<outw_p\>' --or \ -e '\<outl_p\>' --or \ -e '\<insb\>' --or \ -e '\<insw\>' --or \ -e '\<insl\>' --or \ -e '\<outsb\>' --or \ -e '\<outsw\>' --or \ -e '\<outsl\>' --or \ -e '\<insb_p\>' --or \ -e '\<insw_p\>' --or \ -e '\<insl_p\>' --or \ -e '\<outsb_p\>' --or \ -e '\<outsw_p\>' --or \ -e '\<outsl_p\>' --or \ -e '\<ioread8\>' --or \ -e '\<ioread16\>' --or \ -e '\<ioread32\>' --or \ -e '\<ioread64\>' --or \ -e '\<iowrite8\>' --or \ -e '\<iowrite16\>' --or \ -e '\<iowrite32\>' --or \ -e '\<iowrite64\>' --or \ -e '\<ioread16be\>' --or \ -e '\<ioread32be\>' --or \ -e '\<ioread64be\>' --or \ -e '\<iowrite16be\>' --or \ -e '\<iowrite32be\>' --or \ -e '\<iowrite64be\>' --or \ -e '\<ioread8_rep\>' --or \ -e '\<ioread16_rep\>' --or \ -e '\<ioread32_rep\>' --or \ -e '\<ioread64_rep\>' --or \ -e '\<iowrite8_rep\>' --or \ -e '\<iowrite16_rep\>' --or \ -e '\<iowrite32_rep\>' --or \ -e '\<iowrite64_rep\>' --or \ -e '\<__io_virt\>' --or \ -e '\<pci_iounmap\>' --or \ -e '\<virt_to_phys\>' --or \ -e '\<phys_to_virt\>' --or \ -e '\<ioremap_uc\>' --or \ -e '\<ioremap\>' --or \ -e '\<__ioremap\>' --or \ -e '\<iounmap\>' --or \ -e '\<ioremap\>' --or \ -e '\<ioremap_nocache\>' --or \ -e '\<ioremap_uc\>' --or \ -e '\<ioremap_wc\>' --or \ -e '\<ioremap_wc\>' --or \ -e '\<ioremap_wt\>' --or \ -e '\<ioport_map\>' --or \ -e '\<ioport_unmap\>' --or \ -e '\<ioport_map\>' --or \ -e '\<ioport_unmap\>' --or \ -e '\<xlate_dev_kmem_ptr\>' --or \ -e '\<xlate_dev_mem_ptr\>' --or \ -e '\<unxlate_dev_mem_ptr\>' --or \ -e '\<virt_to_bus\>' --or \ -e '\<bus_to_virt\>' --or \ -e '\<memset_io\>' --or \ -e '\<memcpy_fromio\>' --or \ -e '\<memcpy_toio\>' I also reordered a couple includes when they weren't alphabetical and removed clk.h from kona, replacing it with clk-provider.h because that driver doesn't use clk consumer APIs. Acked-by: Geert Uytterhoeven <geert+renesas@glider.be> Cc: Chen-Yu Tsai <wens@csie.org> Acked-by: Maxime Ripard <maxime.ripard@bootlin.com> Acked-by: Tero Kristo <t-kristo@ti.com> Acked-by: Sekhar Nori <nsekhar@ti.com> Cc: Krzysztof Kozlowski <krzk@kernel.org> Acked-by: Mark Brown <broonie@kernel.org> Cc: Chris Zankel <chris@zankel.net> Acked-by: Max Filippov <jcmvbkbc@gmail.com> Acked-by: John Crispin <john@phrozen.org> Acked-by: Heiko Stuebner <heiko@sntech.de> Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2019-04-19 06:20:22 +08:00
#include <linux/clk-provider.h>
#include <linux/errno.h>
clk: Remove io.h from clk-provider.h Now that we've gotten rid of clk_readl() we can remove io.h from the clk-provider header and push out the io.h include to any code that isn't already including the io.h header but using things like readl/writel, etc. Found with this grep: git grep -l clk-provider.h | grep '.c$' | xargs git grep -L 'linux/io.h' | \ xargs git grep -l \ -e '\<__iowrite32_copy\>' --or \ -e '\<__ioread32_copy\>' --or \ -e '\<__iowrite64_copy\>' --or \ -e '\<ioremap_page_range\>' --or \ -e '\<ioremap_huge_init\>' --or \ -e '\<arch_ioremap_pud_supported\>' --or \ -e '\<arch_ioremap_pmd_supported\>' --or \ -e '\<devm_ioport_map\>' --or \ -e '\<devm_ioport_unmap\>' --or \ -e '\<IOMEM_ERR_PTR\>' --or \ -e '\<devm_ioremap\>' --or \ -e '\<devm_ioremap_nocache\>' --or \ -e '\<devm_ioremap_wc\>' --or \ -e '\<devm_iounmap\>' --or \ -e '\<devm_ioremap_release\>' --or \ -e '\<devm_memremap\>' --or \ -e '\<devm_memunmap\>' --or \ -e '\<__devm_memremap_pages\>' --or \ -e '\<pci_remap_cfgspace\>' --or \ -e '\<arch_has_dev_port\>' --or \ -e '\<arch_phys_wc_add\>' --or \ -e '\<arch_phys_wc_del\>' --or \ -e '\<memremap\>' --or \ -e '\<memunmap\>' --or \ -e '\<arch_io_reserve_memtype_wc\>' --or \ -e '\<arch_io_free_memtype_wc\>' --or \ -e '\<__io_aw\>' --or \ -e '\<__io_pbw\>' --or \ -e '\<__io_paw\>' --or \ -e '\<__io_pbr\>' --or \ -e '\<__io_par\>' --or \ -e '\<__raw_readb\>' --or \ -e '\<__raw_readw\>' --or \ -e '\<__raw_readl\>' --or \ -e '\<__raw_readq\>' --or \ -e '\<__raw_writeb\>' --or \ -e '\<__raw_writew\>' --or \ -e '\<__raw_writel\>' --or \ -e '\<__raw_writeq\>' --or \ -e '\<readb\>' --or \ -e '\<readw\>' --or \ -e '\<readl\>' --or \ -e '\<readq\>' --or \ -e '\<writeb\>' --or \ -e '\<writew\>' --or \ -e '\<writel\>' --or \ -e '\<writeq\>' --or \ -e '\<readb_relaxed\>' --or \ -e '\<readw_relaxed\>' --or \ -e '\<readl_relaxed\>' --or \ -e '\<readq_relaxed\>' --or \ -e '\<writeb_relaxed\>' --or \ -e '\<writew_relaxed\>' --or \ -e '\<writel_relaxed\>' --or \ -e '\<writeq_relaxed\>' --or \ -e '\<readsb\>' --or \ -e '\<readsw\>' --or \ -e '\<readsl\>' --or \ -e '\<readsq\>' --or \ -e '\<writesb\>' --or \ -e '\<writesw\>' --or \ -e '\<writesl\>' --or \ -e '\<writesq\>' --or \ -e '\<inb\>' --or \ -e '\<inw\>' --or \ -e '\<inl\>' --or \ -e '\<outb\>' --or \ -e '\<outw\>' --or \ -e '\<outl\>' --or \ -e '\<inb_p\>' --or \ -e '\<inw_p\>' --or \ -e '\<inl_p\>' --or \ -e '\<outb_p\>' --or \ -e '\<outw_p\>' --or \ -e '\<outl_p\>' --or \ -e '\<insb\>' --or \ -e '\<insw\>' --or \ -e '\<insl\>' --or \ -e '\<outsb\>' --or \ -e '\<outsw\>' --or \ -e '\<outsl\>' --or \ -e '\<insb_p\>' --or \ -e '\<insw_p\>' --or \ -e '\<insl_p\>' --or \ -e '\<outsb_p\>' --or \ -e '\<outsw_p\>' --or \ -e '\<outsl_p\>' --or \ -e '\<ioread8\>' --or \ -e '\<ioread16\>' --or \ -e '\<ioread32\>' --or \ -e '\<ioread64\>' --or \ -e '\<iowrite8\>' --or \ -e '\<iowrite16\>' --or \ -e '\<iowrite32\>' --or \ -e '\<iowrite64\>' --or \ -e '\<ioread16be\>' --or \ -e '\<ioread32be\>' --or \ -e '\<ioread64be\>' --or \ -e '\<iowrite16be\>' --or \ -e '\<iowrite32be\>' --or \ -e '\<iowrite64be\>' --or \ -e '\<ioread8_rep\>' --or \ -e '\<ioread16_rep\>' --or \ -e '\<ioread32_rep\>' --or \ -e '\<ioread64_rep\>' --or \ -e '\<iowrite8_rep\>' --or \ -e '\<iowrite16_rep\>' --or \ -e '\<iowrite32_rep\>' --or \ -e '\<iowrite64_rep\>' --or \ -e '\<__io_virt\>' --or \ -e '\<pci_iounmap\>' --or \ -e '\<virt_to_phys\>' --or \ -e '\<phys_to_virt\>' --or \ -e '\<ioremap_uc\>' --or \ -e '\<ioremap\>' --or \ -e '\<__ioremap\>' --or \ -e '\<iounmap\>' --or \ -e '\<ioremap\>' --or \ -e '\<ioremap_nocache\>' --or \ -e '\<ioremap_uc\>' --or \ -e '\<ioremap_wc\>' --or \ -e '\<ioremap_wc\>' --or \ -e '\<ioremap_wt\>' --or \ -e '\<ioport_map\>' --or \ -e '\<ioport_unmap\>' --or \ -e '\<ioport_map\>' --or \ -e '\<ioport_unmap\>' --or \ -e '\<xlate_dev_kmem_ptr\>' --or \ -e '\<xlate_dev_mem_ptr\>' --or \ -e '\<unxlate_dev_mem_ptr\>' --or \ -e '\<virt_to_bus\>' --or \ -e '\<bus_to_virt\>' --or \ -e '\<memset_io\>' --or \ -e '\<memcpy_fromio\>' --or \ -e '\<memcpy_toio\>' I also reordered a couple includes when they weren't alphabetical and removed clk.h from kona, replacing it with clk-provider.h because that driver doesn't use clk consumer APIs. Acked-by: Geert Uytterhoeven <geert+renesas@glider.be> Cc: Chen-Yu Tsai <wens@csie.org> Acked-by: Maxime Ripard <maxime.ripard@bootlin.com> Acked-by: Tero Kristo <t-kristo@ti.com> Acked-by: Sekhar Nori <nsekhar@ti.com> Cc: Krzysztof Kozlowski <krzk@kernel.org> Acked-by: Mark Brown <broonie@kernel.org> Cc: Chris Zankel <chris@zankel.net> Acked-by: Max Filippov <jcmvbkbc@gmail.com> Acked-by: John Crispin <john@phrozen.org> Acked-by: Heiko Stuebner <heiko@sntech.de> Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2019-04-19 06:20:22 +08:00
#include <linux/io.h>
#include <linux/slab.h>
#include "clk.h"
#define PCG_PREDIV_SHIFT 16
#define PCG_PREDIV_WIDTH 3
#define PCG_PREDIV_MAX 8
#define PCG_DIV_SHIFT 0
#define PCG_CORE_DIV_WIDTH 3
#define PCG_DIV_WIDTH 6
#define PCG_DIV_MAX 64
#define PCG_PCS_SHIFT 24
#define PCG_PCS_MASK 0x7
#define PCG_CGC_SHIFT 28
static unsigned long imx8m_clk_composite_divider_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
struct clk_divider *divider = to_clk_divider(hw);
unsigned long prediv_rate;
unsigned int prediv_value;
unsigned int div_value;
prediv_value = readl(divider->reg) >> divider->shift;
prediv_value &= clk_div_mask(divider->width);
prediv_rate = divider_recalc_rate(hw, parent_rate, prediv_value,
NULL, divider->flags,
divider->width);
div_value = readl(divider->reg) >> PCG_DIV_SHIFT;
div_value &= clk_div_mask(PCG_DIV_WIDTH);
return divider_recalc_rate(hw, prediv_rate, div_value, NULL,
divider->flags, PCG_DIV_WIDTH);
}
static int imx8m_clk_composite_compute_dividers(unsigned long rate,
unsigned long parent_rate,
int *prediv, int *postdiv)
{
int div1, div2;
int error = INT_MAX;
int ret = -EINVAL;
*prediv = 1;
*postdiv = 1;
for (div1 = 1; div1 <= PCG_PREDIV_MAX; div1++) {
for (div2 = 1; div2 <= PCG_DIV_MAX; div2++) {
int new_error = ((parent_rate / div1) / div2) - rate;
if (abs(new_error) < abs(error)) {
*prediv = div1;
*postdiv = div2;
error = new_error;
ret = 0;
}
}
}
return ret;
}
static long imx8m_clk_composite_divider_round_rate(struct clk_hw *hw,
unsigned long rate,
unsigned long *prate)
{
int prediv_value;
int div_value;
imx8m_clk_composite_compute_dividers(rate, *prate,
&prediv_value, &div_value);
rate = DIV_ROUND_UP(*prate, prediv_value);
return DIV_ROUND_UP(rate, div_value);
}
static int imx8m_clk_composite_divider_set_rate(struct clk_hw *hw,
unsigned long rate,
unsigned long parent_rate)
{
struct clk_divider *divider = to_clk_divider(hw);
unsigned long flags;
int prediv_value;
int div_value;
int ret;
u32 val;
ret = imx8m_clk_composite_compute_dividers(rate, parent_rate,
&prediv_value, &div_value);
if (ret)
return -EINVAL;
spin_lock_irqsave(divider->lock, flags);
val = readl(divider->reg);
val &= ~((clk_div_mask(divider->width) << divider->shift) |
(clk_div_mask(PCG_DIV_WIDTH) << PCG_DIV_SHIFT));
val |= (u32)(prediv_value - 1) << divider->shift;
val |= (u32)(div_value - 1) << PCG_DIV_SHIFT;
writel(val, divider->reg);
spin_unlock_irqrestore(divider->lock, flags);
return ret;
}
static const struct clk_ops imx8m_clk_composite_divider_ops = {
.recalc_rate = imx8m_clk_composite_divider_recalc_rate,
.round_rate = imx8m_clk_composite_divider_round_rate,
.set_rate = imx8m_clk_composite_divider_set_rate,
};
clk: imx: add mux ops for i.MX8M composite clk The CORE/BUS root slice has following design, simplied graph: The difference is core not have pre_div block. A composite core/bus clk has 8 inputs for mux to select, saying clk[0-7]. It support target(smart) interface and normal interface. Target interface is exported for programmer easy to configure ccm root. Normal interface is also exported, but we not use it in our driver, because it will introduce more complexity compared with target interface. The normal interface simplified as below: SEL_A GA +--+ +-+ | +->+ +------+ CLK[0-7]--->+ | +-+ | | | | +----v---+ +----+ | +--+ |pre_diva+----> | +---------+ | +--------+ |mux +--+post_div | | +--+ |pre_divb+--->+ | +---------+ | | | +----^---+ +----+ +--->+ | +-+ | | +->+ +------+ +--+ +-+ SEL_B GB The mux in the upper pic is not the target interface MUX, target interface MUX is hiding SEL_A and SEL_B. When you choose clk[0-7], you are actually writing SEL_A or SEL_B depends on the internal counter which will also control the internal "mux". The target interface simplified as below which is used by Linux Kernel: CLK[0-7]--->MUX-->Gate-->pre_div-->post_div A requirement of the Target Interface's software is that the target clock source is active, it means when setting SEL_A, the current input clk to SEL_A must be active, same to SEL_B. We touch target interface, but hardware logic actually also need configure normal interface. There will be system hang, when doing the following steps: The initial state: SEL_A/SEL_B are both sourcing from clk0, the internal counter choose SEL_A. 1. switch mux from clk0 to clk1 The hardware logic will choose SEL_B and configure SEL_B to clk1. SEL_A no changed. 2. gate off clk0 Disable clk0, then the input to SEL_A is off. 3. swtich from clk1 to clk2 The hardware logic will choose SEL_A and configure SEL_A to clk2, however the current SEL_A input clk0 is off, the system hang. The solution to fix the issue is in step 1, write twice to target interface MUX, it will make SEL_A/SEL_B both sources from clk1, then no need to care about the state of clk0. And finally system performs well. Signed-off-by: Peng Fan <peng.fan@nxp.com> Reviewed-by: Dong Aisheng <aisheng.dong@nxp.com> Signed-off-by: Shawn Guo <shawnguo@kernel.org>
2020-05-07 13:56:16 +08:00
static u8 imx8m_clk_composite_mux_get_parent(struct clk_hw *hw)
{
return clk_mux_ops.get_parent(hw);
}
static int imx8m_clk_composite_mux_set_parent(struct clk_hw *hw, u8 index)
{
struct clk_mux *mux = to_clk_mux(hw);
u32 val = clk_mux_index_to_val(mux->table, mux->flags, index);
unsigned long flags = 0;
u32 reg;
if (mux->lock)
spin_lock_irqsave(mux->lock, flags);
reg = readl(mux->reg);
reg &= ~(mux->mask << mux->shift);
val = val << mux->shift;
reg |= val;
/*
* write twice to make sure non-target interface
* SEL_A/B point the same clk input.
*/
writel(reg, mux->reg);
writel(reg, mux->reg);
if (mux->lock)
spin_unlock_irqrestore(mux->lock, flags);
return 0;
}
static int
imx8m_clk_composite_mux_determine_rate(struct clk_hw *hw,
struct clk_rate_request *req)
{
return clk_mux_ops.determine_rate(hw, req);
}
static const struct clk_ops imx8m_clk_composite_mux_ops = {
.get_parent = imx8m_clk_composite_mux_get_parent,
.set_parent = imx8m_clk_composite_mux_set_parent,
.determine_rate = imx8m_clk_composite_mux_determine_rate,
};
struct clk_hw *imx8m_clk_hw_composite_flags(const char *name,
const char * const *parent_names,
int num_parents, void __iomem *reg,
u32 composite_flags,
unsigned long flags)
{
struct clk_hw *hw = ERR_PTR(-ENOMEM), *mux_hw;
struct clk_hw *div_hw, *gate_hw;
struct clk_divider *div = NULL;
struct clk_gate *gate = NULL;
struct clk_mux *mux = NULL;
const struct clk_ops *divider_ops;
clk: imx: add mux ops for i.MX8M composite clk The CORE/BUS root slice has following design, simplied graph: The difference is core not have pre_div block. A composite core/bus clk has 8 inputs for mux to select, saying clk[0-7]. It support target(smart) interface and normal interface. Target interface is exported for programmer easy to configure ccm root. Normal interface is also exported, but we not use it in our driver, because it will introduce more complexity compared with target interface. The normal interface simplified as below: SEL_A GA +--+ +-+ | +->+ +------+ CLK[0-7]--->+ | +-+ | | | | +----v---+ +----+ | +--+ |pre_diva+----> | +---------+ | +--------+ |mux +--+post_div | | +--+ |pre_divb+--->+ | +---------+ | | | +----^---+ +----+ +--->+ | +-+ | | +->+ +------+ +--+ +-+ SEL_B GB The mux in the upper pic is not the target interface MUX, target interface MUX is hiding SEL_A and SEL_B. When you choose clk[0-7], you are actually writing SEL_A or SEL_B depends on the internal counter which will also control the internal "mux". The target interface simplified as below which is used by Linux Kernel: CLK[0-7]--->MUX-->Gate-->pre_div-->post_div A requirement of the Target Interface's software is that the target clock source is active, it means when setting SEL_A, the current input clk to SEL_A must be active, same to SEL_B. We touch target interface, but hardware logic actually also need configure normal interface. There will be system hang, when doing the following steps: The initial state: SEL_A/SEL_B are both sourcing from clk0, the internal counter choose SEL_A. 1. switch mux from clk0 to clk1 The hardware logic will choose SEL_B and configure SEL_B to clk1. SEL_A no changed. 2. gate off clk0 Disable clk0, then the input to SEL_A is off. 3. swtich from clk1 to clk2 The hardware logic will choose SEL_A and configure SEL_A to clk2, however the current SEL_A input clk0 is off, the system hang. The solution to fix the issue is in step 1, write twice to target interface MUX, it will make SEL_A/SEL_B both sources from clk1, then no need to care about the state of clk0. And finally system performs well. Signed-off-by: Peng Fan <peng.fan@nxp.com> Reviewed-by: Dong Aisheng <aisheng.dong@nxp.com> Signed-off-by: Shawn Guo <shawnguo@kernel.org>
2020-05-07 13:56:16 +08:00
const struct clk_ops *mux_ops;
mux = kzalloc(sizeof(*mux), GFP_KERNEL);
if (!mux)
goto fail;
mux_hw = &mux->hw;
mux->reg = reg;
mux->shift = PCG_PCS_SHIFT;
mux->mask = PCG_PCS_MASK;
mux->lock = &imx_ccm_lock;
div = kzalloc(sizeof(*div), GFP_KERNEL);
if (!div)
goto fail;
div_hw = &div->hw;
div->reg = reg;
if (composite_flags & IMX_COMPOSITE_CORE) {
div->shift = PCG_DIV_SHIFT;
div->width = PCG_CORE_DIV_WIDTH;
divider_ops = &clk_divider_ops;
clk: imx: add mux ops for i.MX8M composite clk The CORE/BUS root slice has following design, simplied graph: The difference is core not have pre_div block. A composite core/bus clk has 8 inputs for mux to select, saying clk[0-7]. It support target(smart) interface and normal interface. Target interface is exported for programmer easy to configure ccm root. Normal interface is also exported, but we not use it in our driver, because it will introduce more complexity compared with target interface. The normal interface simplified as below: SEL_A GA +--+ +-+ | +->+ +------+ CLK[0-7]--->+ | +-+ | | | | +----v---+ +----+ | +--+ |pre_diva+----> | +---------+ | +--------+ |mux +--+post_div | | +--+ |pre_divb+--->+ | +---------+ | | | +----^---+ +----+ +--->+ | +-+ | | +->+ +------+ +--+ +-+ SEL_B GB The mux in the upper pic is not the target interface MUX, target interface MUX is hiding SEL_A and SEL_B. When you choose clk[0-7], you are actually writing SEL_A or SEL_B depends on the internal counter which will also control the internal "mux". The target interface simplified as below which is used by Linux Kernel: CLK[0-7]--->MUX-->Gate-->pre_div-->post_div A requirement of the Target Interface's software is that the target clock source is active, it means when setting SEL_A, the current input clk to SEL_A must be active, same to SEL_B. We touch target interface, but hardware logic actually also need configure normal interface. There will be system hang, when doing the following steps: The initial state: SEL_A/SEL_B are both sourcing from clk0, the internal counter choose SEL_A. 1. switch mux from clk0 to clk1 The hardware logic will choose SEL_B and configure SEL_B to clk1. SEL_A no changed. 2. gate off clk0 Disable clk0, then the input to SEL_A is off. 3. swtich from clk1 to clk2 The hardware logic will choose SEL_A and configure SEL_A to clk2, however the current SEL_A input clk0 is off, the system hang. The solution to fix the issue is in step 1, write twice to target interface MUX, it will make SEL_A/SEL_B both sources from clk1, then no need to care about the state of clk0. And finally system performs well. Signed-off-by: Peng Fan <peng.fan@nxp.com> Reviewed-by: Dong Aisheng <aisheng.dong@nxp.com> Signed-off-by: Shawn Guo <shawnguo@kernel.org>
2020-05-07 13:56:16 +08:00
mux_ops = &imx8m_clk_composite_mux_ops;
} else {
div->shift = PCG_PREDIV_SHIFT;
div->width = PCG_PREDIV_WIDTH;
divider_ops = &imx8m_clk_composite_divider_ops;
clk: imx: add mux ops for i.MX8M composite clk The CORE/BUS root slice has following design, simplied graph: The difference is core not have pre_div block. A composite core/bus clk has 8 inputs for mux to select, saying clk[0-7]. It support target(smart) interface and normal interface. Target interface is exported for programmer easy to configure ccm root. Normal interface is also exported, but we not use it in our driver, because it will introduce more complexity compared with target interface. The normal interface simplified as below: SEL_A GA +--+ +-+ | +->+ +------+ CLK[0-7]--->+ | +-+ | | | | +----v---+ +----+ | +--+ |pre_diva+----> | +---------+ | +--------+ |mux +--+post_div | | +--+ |pre_divb+--->+ | +---------+ | | | +----^---+ +----+ +--->+ | +-+ | | +->+ +------+ +--+ +-+ SEL_B GB The mux in the upper pic is not the target interface MUX, target interface MUX is hiding SEL_A and SEL_B. When you choose clk[0-7], you are actually writing SEL_A or SEL_B depends on the internal counter which will also control the internal "mux". The target interface simplified as below which is used by Linux Kernel: CLK[0-7]--->MUX-->Gate-->pre_div-->post_div A requirement of the Target Interface's software is that the target clock source is active, it means when setting SEL_A, the current input clk to SEL_A must be active, same to SEL_B. We touch target interface, but hardware logic actually also need configure normal interface. There will be system hang, when doing the following steps: The initial state: SEL_A/SEL_B are both sourcing from clk0, the internal counter choose SEL_A. 1. switch mux from clk0 to clk1 The hardware logic will choose SEL_B and configure SEL_B to clk1. SEL_A no changed. 2. gate off clk0 Disable clk0, then the input to SEL_A is off. 3. swtich from clk1 to clk2 The hardware logic will choose SEL_A and configure SEL_A to clk2, however the current SEL_A input clk0 is off, the system hang. The solution to fix the issue is in step 1, write twice to target interface MUX, it will make SEL_A/SEL_B both sources from clk1, then no need to care about the state of clk0. And finally system performs well. Signed-off-by: Peng Fan <peng.fan@nxp.com> Reviewed-by: Dong Aisheng <aisheng.dong@nxp.com> Signed-off-by: Shawn Guo <shawnguo@kernel.org>
2020-05-07 13:56:16 +08:00
mux_ops = &clk_mux_ops;
}
div->lock = &imx_ccm_lock;
div->flags = CLK_DIVIDER_ROUND_CLOSEST;
gate = kzalloc(sizeof(*gate), GFP_KERNEL);
if (!gate)
goto fail;
gate_hw = &gate->hw;
gate->reg = reg;
gate->bit_idx = PCG_CGC_SHIFT;
gate->lock = &imx_ccm_lock;
hw = clk_hw_register_composite(NULL, name, parent_names, num_parents,
clk: imx: add mux ops for i.MX8M composite clk The CORE/BUS root slice has following design, simplied graph: The difference is core not have pre_div block. A composite core/bus clk has 8 inputs for mux to select, saying clk[0-7]. It support target(smart) interface and normal interface. Target interface is exported for programmer easy to configure ccm root. Normal interface is also exported, but we not use it in our driver, because it will introduce more complexity compared with target interface. The normal interface simplified as below: SEL_A GA +--+ +-+ | +->+ +------+ CLK[0-7]--->+ | +-+ | | | | +----v---+ +----+ | +--+ |pre_diva+----> | +---------+ | +--------+ |mux +--+post_div | | +--+ |pre_divb+--->+ | +---------+ | | | +----^---+ +----+ +--->+ | +-+ | | +->+ +------+ +--+ +-+ SEL_B GB The mux in the upper pic is not the target interface MUX, target interface MUX is hiding SEL_A and SEL_B. When you choose clk[0-7], you are actually writing SEL_A or SEL_B depends on the internal counter which will also control the internal "mux". The target interface simplified as below which is used by Linux Kernel: CLK[0-7]--->MUX-->Gate-->pre_div-->post_div A requirement of the Target Interface's software is that the target clock source is active, it means when setting SEL_A, the current input clk to SEL_A must be active, same to SEL_B. We touch target interface, but hardware logic actually also need configure normal interface. There will be system hang, when doing the following steps: The initial state: SEL_A/SEL_B are both sourcing from clk0, the internal counter choose SEL_A. 1. switch mux from clk0 to clk1 The hardware logic will choose SEL_B and configure SEL_B to clk1. SEL_A no changed. 2. gate off clk0 Disable clk0, then the input to SEL_A is off. 3. swtich from clk1 to clk2 The hardware logic will choose SEL_A and configure SEL_A to clk2, however the current SEL_A input clk0 is off, the system hang. The solution to fix the issue is in step 1, write twice to target interface MUX, it will make SEL_A/SEL_B both sources from clk1, then no need to care about the state of clk0. And finally system performs well. Signed-off-by: Peng Fan <peng.fan@nxp.com> Reviewed-by: Dong Aisheng <aisheng.dong@nxp.com> Signed-off-by: Shawn Guo <shawnguo@kernel.org>
2020-05-07 13:56:16 +08:00
mux_hw, mux_ops, div_hw,
divider_ops, gate_hw, &clk_gate_ops, flags);
if (IS_ERR(hw))
goto fail;
return hw;
fail:
kfree(gate);
kfree(div);
kfree(mux);
return ERR_CAST(hw);
}