linux/drivers/clk/imx/clk-imx35.c
Adam Ford 379c9a24cc clk: imx: Fix reparenting of UARTs not associated with stdout
Most if not all i.MX SoC's call a function which enables all UARTS.
This is a problem for users who need to re-parent the clock source,
because any attempt to change the parent results in an busy error
due to the fact that the clocks have been enabled already.

  clk: failed to reparent uart1 to sys_pll1_80m: -16

Instead of pre-initializing all UARTS, scan the device tree to see
which UART clocks are associated to stdout, and only enable those
UART clocks if it's needed early.  This will move initialization of
the remaining clocks until after the parenting of the clocks.

When the clocks are shutdown, this mechanism will also disable any
clocks that were pre-initialized.

Fixes: 9461f7b33d ("clk: fix CLK_SET_RATE_GATE with clock rate protection")
Suggested-by: Aisheng Dong <aisheng.dong@nxp.com>
Signed-off-by: Adam Ford <aford173@gmail.com>
Reviewed-by: Abel Vesa <abel.vesa@nxp.com>
Tested-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Signed-off-by: Abel Vesa <abel.vesa@nxp.com>
2021-04-04 22:39:04 +03:00

252 lines
11 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2012 Sascha Hauer, Pengutronix <s.hauer@pengutronix.de>
*/
#include <linux/mm.h>
#include <linux/delay.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/clkdev.h>
#include <linux/of.h>
#include <linux/err.h>
#include <soc/imx/revision.h>
#include <soc/imx/timer.h>
#include <asm/irq.h>
#include "clk.h"
#define MX35_CCM_BASE_ADDR 0x53f80000
#define MX35_GPT1_BASE_ADDR 0x53f90000
#define MX35_INT_GPT (NR_IRQS_LEGACY + 29)
#define MXC_CCM_PDR0 0x04
#define MX35_CCM_PDR2 0x0c
#define MX35_CCM_PDR3 0x10
#define MX35_CCM_PDR4 0x14
#define MX35_CCM_MPCTL 0x1c
#define MX35_CCM_PPCTL 0x20
#define MX35_CCM_CGR0 0x2c
#define MX35_CCM_CGR1 0x30
#define MX35_CCM_CGR2 0x34
#define MX35_CCM_CGR3 0x38
struct arm_ahb_div {
unsigned char arm, ahb, sel;
};
static struct arm_ahb_div clk_consumer[] = {
{ .arm = 1, .ahb = 4, .sel = 0},
{ .arm = 1, .ahb = 3, .sel = 1},
{ .arm = 2, .ahb = 2, .sel = 0},
{ .arm = 0, .ahb = 0, .sel = 0},
{ .arm = 0, .ahb = 0, .sel = 0},
{ .arm = 0, .ahb = 0, .sel = 0},
{ .arm = 4, .ahb = 1, .sel = 0},
{ .arm = 1, .ahb = 5, .sel = 0},
{ .arm = 1, .ahb = 8, .sel = 0},
{ .arm = 1, .ahb = 6, .sel = 1},
{ .arm = 2, .ahb = 4, .sel = 0},
{ .arm = 0, .ahb = 0, .sel = 0},
{ .arm = 0, .ahb = 0, .sel = 0},
{ .arm = 0, .ahb = 0, .sel = 0},
{ .arm = 4, .ahb = 2, .sel = 0},
{ .arm = 0, .ahb = 0, .sel = 0},
};
static char hsp_div_532[] = { 4, 8, 3, 0 };
static char hsp_div_400[] = { 3, 6, 3, 0 };
static struct clk_onecell_data clk_data;
static const char *std_sel[] = {"ppll", "arm"};
static const char *ipg_per_sel[] = {"ahb_per_div", "arm_per_div"};
enum mx35_clks {
/* 0 */ ckih, mpll, ppll, mpll_075, arm, hsp, hsp_div, hsp_sel, ahb,
/* 9 */ ipg, arm_per_div, ahb_per_div, ipg_per, uart_sel, uart_div,
/* 15 */ esdhc_sel, esdhc1_div, esdhc2_div, esdhc3_div, spdif_sel,
/* 20 */ spdif_div_pre, spdif_div_post, ssi_sel, ssi1_div_pre,
/* 24 */ ssi1_div_post, ssi2_div_pre, ssi2_div_post, usb_sel, usb_div,
/* 29 */ nfc_div, asrc_gate, pata_gate, audmux_gate, can1_gate,
/* 34 */ can2_gate, cspi1_gate, cspi2_gate, ect_gate, edio_gate,
/* 39 */ emi_gate, epit1_gate, epit2_gate, esai_gate, esdhc1_gate,
/* 44 */ esdhc2_gate, esdhc3_gate, fec_gate, gpio1_gate, gpio2_gate,
/* 49 */ gpio3_gate, gpt_gate, i2c1_gate, i2c2_gate, i2c3_gate,
/* 54 */ iomuxc_gate, ipu_gate, kpp_gate, mlb_gate, mshc_gate,
/* 59 */ owire_gate, pwm_gate, rngc_gate, rtc_gate, rtic_gate, scc_gate,
/* 65 */ sdma_gate, spba_gate, spdif_gate, ssi1_gate, ssi2_gate,
/* 70 */ uart1_gate, uart2_gate, uart3_gate, usbotg_gate, wdog_gate,
/* 75 */ max_gate, admux_gate, csi_gate, csi_div, csi_sel, iim_gate,
/* 81 */ gpu2d_gate, ckil, clk_max
};
static struct clk *clk[clk_max];
static void __init _mx35_clocks_init(void)
{
void __iomem *base;
u32 pdr0, consumer_sel, hsp_sel;
struct arm_ahb_div *aad;
unsigned char *hsp_div;
base = ioremap(MX35_CCM_BASE_ADDR, SZ_4K);
BUG_ON(!base);
pdr0 = __raw_readl(base + MXC_CCM_PDR0);
consumer_sel = (pdr0 >> 16) & 0xf;
aad = &clk_consumer[consumer_sel];
if (!aad->arm) {
pr_err("i.MX35 clk: illegal consumer mux selection 0x%x\n", consumer_sel);
/*
* We are basically stuck. Continue with a default entry and hope we
* get far enough to actually show the above message
*/
aad = &clk_consumer[0];
}
clk[ckih] = imx_clk_fixed("ckih", 24000000);
clk[ckil] = imx_clk_fixed("ckil", 32768);
clk[mpll] = imx_clk_pllv1(IMX_PLLV1_IMX35, "mpll", "ckih", base + MX35_CCM_MPCTL);
clk[ppll] = imx_clk_pllv1(IMX_PLLV1_IMX35, "ppll", "ckih", base + MX35_CCM_PPCTL);
clk[mpll] = imx_clk_fixed_factor("mpll_075", "mpll", 3, 4);
if (aad->sel)
clk[arm] = imx_clk_fixed_factor("arm", "mpll_075", 1, aad->arm);
else
clk[arm] = imx_clk_fixed_factor("arm", "mpll", 1, aad->arm);
if (clk_get_rate(clk[arm]) > 400000000)
hsp_div = hsp_div_532;
else
hsp_div = hsp_div_400;
hsp_sel = (pdr0 >> 20) & 0x3;
if (!hsp_div[hsp_sel]) {
pr_err("i.MX35 clk: illegal hsp clk selection 0x%x\n", hsp_sel);
hsp_sel = 0;
}
clk[hsp] = imx_clk_fixed_factor("hsp", "arm", 1, hsp_div[hsp_sel]);
clk[ahb] = imx_clk_fixed_factor("ahb", "arm", 1, aad->ahb);
clk[ipg] = imx_clk_fixed_factor("ipg", "ahb", 1, 2);
clk[arm_per_div] = imx_clk_divider("arm_per_div", "arm", base + MX35_CCM_PDR4, 16, 6);
clk[ahb_per_div] = imx_clk_divider("ahb_per_div", "ahb", base + MXC_CCM_PDR0, 12, 3);
clk[ipg_per] = imx_clk_mux("ipg_per", base + MXC_CCM_PDR0, 26, 1, ipg_per_sel, ARRAY_SIZE(ipg_per_sel));
clk[uart_sel] = imx_clk_mux("uart_sel", base + MX35_CCM_PDR3, 14, 1, std_sel, ARRAY_SIZE(std_sel));
clk[uart_div] = imx_clk_divider("uart_div", "uart_sel", base + MX35_CCM_PDR4, 10, 6);
clk[esdhc_sel] = imx_clk_mux("esdhc_sel", base + MX35_CCM_PDR4, 9, 1, std_sel, ARRAY_SIZE(std_sel));
clk[esdhc1_div] = imx_clk_divider("esdhc1_div", "esdhc_sel", base + MX35_CCM_PDR3, 0, 6);
clk[esdhc2_div] = imx_clk_divider("esdhc2_div", "esdhc_sel", base + MX35_CCM_PDR3, 8, 6);
clk[esdhc3_div] = imx_clk_divider("esdhc3_div", "esdhc_sel", base + MX35_CCM_PDR3, 16, 6);
clk[spdif_sel] = imx_clk_mux("spdif_sel", base + MX35_CCM_PDR3, 22, 1, std_sel, ARRAY_SIZE(std_sel));
clk[spdif_div_pre] = imx_clk_divider("spdif_div_pre", "spdif_sel", base + MX35_CCM_PDR3, 29, 3); /* divide by 1 not allowed */
clk[spdif_div_post] = imx_clk_divider("spdif_div_post", "spdif_div_pre", base + MX35_CCM_PDR3, 23, 6);
clk[ssi_sel] = imx_clk_mux("ssi_sel", base + MX35_CCM_PDR2, 6, 1, std_sel, ARRAY_SIZE(std_sel));
clk[ssi1_div_pre] = imx_clk_divider("ssi1_div_pre", "ssi_sel", base + MX35_CCM_PDR2, 24, 3);
clk[ssi1_div_post] = imx_clk_divider("ssi1_div_post", "ssi1_div_pre", base + MX35_CCM_PDR2, 0, 6);
clk[ssi2_div_pre] = imx_clk_divider("ssi2_div_pre", "ssi_sel", base + MX35_CCM_PDR2, 27, 3);
clk[ssi2_div_post] = imx_clk_divider("ssi2_div_post", "ssi2_div_pre", base + MX35_CCM_PDR2, 8, 6);
clk[usb_sel] = imx_clk_mux("usb_sel", base + MX35_CCM_PDR4, 9, 1, std_sel, ARRAY_SIZE(std_sel));
clk[usb_div] = imx_clk_divider("usb_div", "usb_sel", base + MX35_CCM_PDR4, 22, 6);
clk[nfc_div] = imx_clk_divider("nfc_div", "ahb", base + MX35_CCM_PDR4, 28, 4);
clk[csi_sel] = imx_clk_mux("csi_sel", base + MX35_CCM_PDR2, 7, 1, std_sel, ARRAY_SIZE(std_sel));
clk[csi_div] = imx_clk_divider("csi_div", "csi_sel", base + MX35_CCM_PDR2, 16, 6);
clk[asrc_gate] = imx_clk_gate2("asrc_gate", "ipg", base + MX35_CCM_CGR0, 0);
clk[pata_gate] = imx_clk_gate2("pata_gate", "ipg", base + MX35_CCM_CGR0, 2);
clk[audmux_gate] = imx_clk_gate2("audmux_gate", "ipg", base + MX35_CCM_CGR0, 4);
clk[can1_gate] = imx_clk_gate2("can1_gate", "ipg", base + MX35_CCM_CGR0, 6);
clk[can2_gate] = imx_clk_gate2("can2_gate", "ipg", base + MX35_CCM_CGR0, 8);
clk[cspi1_gate] = imx_clk_gate2("cspi1_gate", "ipg", base + MX35_CCM_CGR0, 10);
clk[cspi2_gate] = imx_clk_gate2("cspi2_gate", "ipg", base + MX35_CCM_CGR0, 12);
clk[ect_gate] = imx_clk_gate2("ect_gate", "ipg", base + MX35_CCM_CGR0, 14);
clk[edio_gate] = imx_clk_gate2("edio_gate", "ipg", base + MX35_CCM_CGR0, 16);
clk[emi_gate] = imx_clk_gate2("emi_gate", "ipg", base + MX35_CCM_CGR0, 18);
clk[epit1_gate] = imx_clk_gate2("epit1_gate", "ipg", base + MX35_CCM_CGR0, 20);
clk[epit2_gate] = imx_clk_gate2("epit2_gate", "ipg", base + MX35_CCM_CGR0, 22);
clk[esai_gate] = imx_clk_gate2("esai_gate", "ipg", base + MX35_CCM_CGR0, 24);
clk[esdhc1_gate] = imx_clk_gate2("esdhc1_gate", "esdhc1_div", base + MX35_CCM_CGR0, 26);
clk[esdhc2_gate] = imx_clk_gate2("esdhc2_gate", "esdhc2_div", base + MX35_CCM_CGR0, 28);
clk[esdhc3_gate] = imx_clk_gate2("esdhc3_gate", "esdhc3_div", base + MX35_CCM_CGR0, 30);
clk[fec_gate] = imx_clk_gate2("fec_gate", "ipg", base + MX35_CCM_CGR1, 0);
clk[gpio1_gate] = imx_clk_gate2("gpio1_gate", "ipg", base + MX35_CCM_CGR1, 2);
clk[gpio2_gate] = imx_clk_gate2("gpio2_gate", "ipg", base + MX35_CCM_CGR1, 4);
clk[gpio3_gate] = imx_clk_gate2("gpio3_gate", "ipg", base + MX35_CCM_CGR1, 6);
clk[gpt_gate] = imx_clk_gate2("gpt_gate", "ipg", base + MX35_CCM_CGR1, 8);
clk[i2c1_gate] = imx_clk_gate2("i2c1_gate", "ipg_per", base + MX35_CCM_CGR1, 10);
clk[i2c2_gate] = imx_clk_gate2("i2c2_gate", "ipg_per", base + MX35_CCM_CGR1, 12);
clk[i2c3_gate] = imx_clk_gate2("i2c3_gate", "ipg_per", base + MX35_CCM_CGR1, 14);
clk[iomuxc_gate] = imx_clk_gate2("iomuxc_gate", "ipg", base + MX35_CCM_CGR1, 16);
clk[ipu_gate] = imx_clk_gate2("ipu_gate", "hsp", base + MX35_CCM_CGR1, 18);
clk[kpp_gate] = imx_clk_gate2("kpp_gate", "ipg", base + MX35_CCM_CGR1, 20);
clk[mlb_gate] = imx_clk_gate2("mlb_gate", "ahb", base + MX35_CCM_CGR1, 22);
clk[mshc_gate] = imx_clk_gate2("mshc_gate", "dummy", base + MX35_CCM_CGR1, 24);
clk[owire_gate] = imx_clk_gate2("owire_gate", "ipg_per", base + MX35_CCM_CGR1, 26);
clk[pwm_gate] = imx_clk_gate2("pwm_gate", "ipg_per", base + MX35_CCM_CGR1, 28);
clk[rngc_gate] = imx_clk_gate2("rngc_gate", "ipg", base + MX35_CCM_CGR1, 30);
clk[rtc_gate] = imx_clk_gate2("rtc_gate", "ipg", base + MX35_CCM_CGR2, 0);
clk[rtic_gate] = imx_clk_gate2("rtic_gate", "ahb", base + MX35_CCM_CGR2, 2);
clk[scc_gate] = imx_clk_gate2("scc_gate", "ipg", base + MX35_CCM_CGR2, 4);
clk[sdma_gate] = imx_clk_gate2("sdma_gate", "ahb", base + MX35_CCM_CGR2, 6);
clk[spba_gate] = imx_clk_gate2("spba_gate", "ipg", base + MX35_CCM_CGR2, 8);
clk[spdif_gate] = imx_clk_gate2("spdif_gate", "spdif_div_post", base + MX35_CCM_CGR2, 10);
clk[ssi1_gate] = imx_clk_gate2("ssi1_gate", "ssi1_div_post", base + MX35_CCM_CGR2, 12);
clk[ssi2_gate] = imx_clk_gate2("ssi2_gate", "ssi2_div_post", base + MX35_CCM_CGR2, 14);
clk[uart1_gate] = imx_clk_gate2("uart1_gate", "uart_div", base + MX35_CCM_CGR2, 16);
clk[uart2_gate] = imx_clk_gate2("uart2_gate", "uart_div", base + MX35_CCM_CGR2, 18);
clk[uart3_gate] = imx_clk_gate2("uart3_gate", "uart_div", base + MX35_CCM_CGR2, 20);
clk[usbotg_gate] = imx_clk_gate2("usbotg_gate", "ahb", base + MX35_CCM_CGR2, 22);
clk[wdog_gate] = imx_clk_gate2("wdog_gate", "ipg", base + MX35_CCM_CGR2, 24);
clk[max_gate] = imx_clk_gate2("max_gate", "dummy", base + MX35_CCM_CGR2, 26);
clk[admux_gate] = imx_clk_gate2("admux_gate", "ipg", base + MX35_CCM_CGR2, 30);
clk[csi_gate] = imx_clk_gate2("csi_gate", "csi_div", base + MX35_CCM_CGR3, 0);
clk[iim_gate] = imx_clk_gate2("iim_gate", "ipg", base + MX35_CCM_CGR3, 2);
clk[gpu2d_gate] = imx_clk_gate2("gpu2d_gate", "ahb", base + MX35_CCM_CGR3, 4);
imx_check_clocks(clk, ARRAY_SIZE(clk));
clk_prepare_enable(clk[spba_gate]);
clk_prepare_enable(clk[gpio1_gate]);
clk_prepare_enable(clk[gpio2_gate]);
clk_prepare_enable(clk[gpio3_gate]);
clk_prepare_enable(clk[iim_gate]);
clk_prepare_enable(clk[emi_gate]);
clk_prepare_enable(clk[max_gate]);
clk_prepare_enable(clk[iomuxc_gate]);
/*
* SCC is needed to boot via mmc after a watchdog reset. The clock code
* before conversion to common clk also enabled UART1 (which isn't
* handled here and not needed for mmc) and IIM (which is enabled
* unconditionally above).
*/
clk_prepare_enable(clk[scc_gate]);
imx_register_uart_clocks(4);
imx_print_silicon_rev("i.MX35", mx35_revision());
}
static void __init mx35_clocks_init_dt(struct device_node *ccm_node)
{
_mx35_clocks_init();
clk_data.clks = clk;
clk_data.clk_num = ARRAY_SIZE(clk);
of_clk_add_provider(ccm_node, of_clk_src_onecell_get, &clk_data);
}
CLK_OF_DECLARE(imx35, "fsl,imx35-ccm", mx35_clocks_init_dt);