u-boot/arch/arm/mach-snapdragon/clock-apq8016.c

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/*
* Clock drivers for Qualcomm APQ8016
*
* (C) Copyright 2015 Mateusz Kulikowski <mateusz.kulikowski@gmail.com>
*
* Based on Little Kernel driver, simplified
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <common.h>
#include <clk-uclass.h>
#include <dm.h>
#include <errno.h>
#include <asm/io.h>
#include <linux/bitops.h>
/* GPLL0 clock control registers */
#define GPLL0_STATUS 0x2101C
#define GPLL0_STATUS_ACTIVE BIT(17)
#define APCS_GPLL_ENA_VOTE 0x45000
#define APCS_GPLL_ENA_VOTE_GPLL0 BIT(0)
/* vote reg for blsp1 clock */
#define APCS_CLOCK_BRANCH_ENA_VOTE 0x45004
#define APCS_CLOCK_BRANCH_ENA_VOTE_BLSP1 BIT(10)
/* SDC(n) clock control registers; n=1,2 */
/* block control register */
#define SDCC_BCR(n) ((n * 0x1000) + 0x41000)
/* cmd */
#define SDCC_CMD_RCGR(n) ((n * 0x1000) + 0x41004)
/* cfg */
#define SDCC_CFG_RCGR(n) ((n * 0x1000) + 0x41008)
/* m */
#define SDCC_M(n) ((n * 0x1000) + 0x4100C)
/* n */
#define SDCC_N(n) ((n * 0x1000) + 0x41010)
/* d */
#define SDCC_D(n) ((n * 0x1000) + 0x41014)
/* branch control */
#define SDCC_APPS_CBCR(n) ((n * 0x1000) + 0x41018)
#define SDCC_AHB_CBCR(n) ((n * 0x1000) + 0x4101C)
/* BLSP1 AHB clock (root clock for BLSP) */
#define BLSP1_AHB_CBCR 0x1008
/* Uart clock control registers */
#define BLSP1_UART2_BCR 0x3028
#define BLSP1_UART2_APPS_CBCR 0x302C
#define BLSP1_UART2_APPS_CMD_RCGR 0x3034
#define BLSP1_UART2_APPS_CFG_RCGR 0x3038
#define BLSP1_UART2_APPS_M 0x303C
#define BLSP1_UART2_APPS_N 0x3040
#define BLSP1_UART2_APPS_D 0x3044
/* CBCR register fields */
#define CBCR_BRANCH_ENABLE_BIT BIT(0)
#define CBCR_BRANCH_OFF_BIT BIT(31)
struct msm_clk_priv {
phys_addr_t base;
};
/* Enable clock controlled by CBC soft macro */
static void clk_enable_cbc(phys_addr_t cbcr)
{
setbits_le32(cbcr, CBCR_BRANCH_ENABLE_BIT);
while (readl(cbcr) & CBCR_BRANCH_OFF_BIT)
;
}
/* clock has 800MHz */
static void clk_enable_gpll0(phys_addr_t base)
{
if (readl(base + GPLL0_STATUS) & GPLL0_STATUS_ACTIVE)
return; /* clock already enabled */
setbits_le32(base + APCS_GPLL_ENA_VOTE, APCS_GPLL_ENA_VOTE_GPLL0);
while ((readl(base + GPLL0_STATUS) & GPLL0_STATUS_ACTIVE) == 0)
;
}
#define APPS_CMD_RGCR_UPDATE BIT(0)
/* Update clock command via CMD_RGCR */
static void clk_bcr_update(phys_addr_t apps_cmd_rgcr)
{
setbits_le32(apps_cmd_rgcr, APPS_CMD_RGCR_UPDATE);
/* Wait for frequency to be updated. */
while (readl(apps_cmd_rgcr) & APPS_CMD_RGCR_UPDATE)
;
}
struct bcr_regs {
uintptr_t cfg_rcgr;
uintptr_t cmd_rcgr;
uintptr_t M;
uintptr_t N;
uintptr_t D;
};
/* RCGR_CFG register fields */
#define CFG_MODE_DUAL_EDGE (0x2 << 12) /* Counter mode */
/* sources */
#define CFG_CLK_SRC_CXO (0 << 8)
#define CFG_CLK_SRC_GPLL0 (1 << 8)
#define CFG_CLK_SRC_MASK (7 << 8)
/* Mask for supported fields */
#define CFG_MASK 0x3FFF
#define CFG_DIVIDER_MASK 0x1F
/* root set rate for clocks with half integer and MND divider */
static void clk_rcg_set_rate_mnd(phys_addr_t base, const struct bcr_regs *regs,
int div, int m, int n, int source)
{
uint32_t cfg;
/* M value for MND divider. */
uint32_t m_val = m;
/* NOT(N-M) value for MND divider. */
uint32_t n_val = ~((n)-(m)) * !!(n);
/* NOT 2D value for MND divider. */
uint32_t d_val = ~(n);
/* Program MND values */
writel(m_val, base + regs->M);
writel(n_val, base + regs->N);
writel(d_val, base + regs->D);
/* setup src select and divider */
cfg = readl(base + regs->cfg_rcgr);
cfg &= ~CFG_MASK;
cfg |= source & CFG_CLK_SRC_MASK; /* Select clock source */
/* Set the divider; HW permits fraction dividers (+0.5), but
for simplicity, we will support integers only */
if (div)
cfg |= (2 * div - 1) & CFG_DIVIDER_MASK;
if (n_val)
cfg |= CFG_MODE_DUAL_EDGE;
writel(cfg, base + regs->cfg_rcgr); /* Write new clock configuration */
/* Inform h/w to start using the new config. */
clk_bcr_update(base + regs->cmd_rcgr);
}
static const struct bcr_regs sdc_regs[] = {
{
.cfg_rcgr = SDCC_CFG_RCGR(1),
.cmd_rcgr = SDCC_CMD_RCGR(1),
.M = SDCC_M(1),
.N = SDCC_N(1),
.D = SDCC_D(1),
},
{
.cfg_rcgr = SDCC_CFG_RCGR(2),
.cmd_rcgr = SDCC_CMD_RCGR(2),
.M = SDCC_M(2),
.N = SDCC_N(2),
.D = SDCC_D(2),
}
};
/* Init clock for SDHCI controller */
static int clk_init_sdc(struct msm_clk_priv *priv, int slot, uint rate)
{
int div = 8; /* 100MHz default */
if (rate == 200000000)
div = 4;
clk_enable_cbc(priv->base + SDCC_AHB_CBCR(slot));
/* 800Mhz/div, gpll0 */
clk_rcg_set_rate_mnd(priv->base, &sdc_regs[slot], div, 0, 0,
CFG_CLK_SRC_GPLL0);
clk_enable_gpll0(priv->base);
clk_enable_cbc(priv->base + SDCC_APPS_CBCR(slot));
return rate;
}
static const struct bcr_regs uart2_regs = {
.cfg_rcgr = BLSP1_UART2_APPS_CFG_RCGR,
.cmd_rcgr = BLSP1_UART2_APPS_CMD_RCGR,
.M = BLSP1_UART2_APPS_M,
.N = BLSP1_UART2_APPS_N,
.D = BLSP1_UART2_APPS_D,
};
/* Init UART clock, 115200 */
static int clk_init_uart(struct msm_clk_priv *priv)
{
/* Enable iface clk */
clk_enable_cbc(priv->base + BLSP1_AHB_CBCR);
/* 7372800 uart block clock @ GPLL0 */
clk_rcg_set_rate_mnd(priv->base, &uart2_regs, 1, 144, 15625,
CFG_CLK_SRC_GPLL0);
clk_enable_gpll0(priv->base);
/* Enable core clk */
clk_enable_cbc(priv->base + BLSP1_UART2_APPS_CBCR);
return 0;
}
ulong msm_set_rate(struct clk *clk, ulong rate)
{
struct msm_clk_priv *priv = dev_get_priv(clk->dev);
switch (clk->id) {
case 0: /* SDC1 */
return clk_init_sdc(priv, 0, rate);
break;
case 1: /* SDC2 */
return clk_init_sdc(priv, 1, rate);
break;
case 4: /* UART2 */
return clk_init_uart(priv);
break;
default:
return 0;
}
}
static int msm_clk_probe(struct udevice *dev)
{
struct msm_clk_priv *priv = dev_get_priv(dev);
priv->base = devfdt_get_addr(dev);
if (priv->base == FDT_ADDR_T_NONE)
return -EINVAL;
return 0;
}
static struct clk_ops msm_clk_ops = {
.set_rate = msm_set_rate,
};
static const struct udevice_id msm_clk_ids[] = {
{ .compatible = "qcom,gcc-msm8916" },
{ .compatible = "qcom,gcc-apq8016" },
{ }
};
U_BOOT_DRIVER(clk_msm) = {
.name = "clk_msm",
.id = UCLASS_CLK,
.of_match = msm_clk_ids,
.ops = &msm_clk_ops,
.priv_auto_alloc_size = sizeof(struct msm_clk_priv),
.probe = msm_clk_probe,
};