From 9fe69429509858d9db6ae123c4cb078351ec2623 Mon Sep 17 00:00:00 2001 From: Robert Jarzmik Date: Wed, 2 Nov 2016 22:33:06 +0100 Subject: [PATCH] clk: pxa: transfer CPU clock setting from pxa2xx-cpufreq This is the initial stage to transfer the pxa25x and pxa27x CPU clocks handling from cpufreq to the clock API. More precisely, the clocks transferred are : - cpll : core pll, known also as the CPU core turbo frequency - core : core, known also as the CPU actual frequency, being either the CPU core turbo frequency or the CPU core run frequency This transfer is a prequel to shrink the code in pxa2xx-cpufreq.c, so that it can become, at least in devicetree builds, the casual cpufreq-dt driver. Signed-off-by: Robert Jarzmik Signed-off-by: Stephen Boyd --- drivers/clk/pxa/clk-pxa.c | 139 +++++++++++++++++++++++++++++++++ drivers/clk/pxa/clk-pxa.h | 57 +++++++++++++- drivers/clk/pxa/clk-pxa25x.c | 101 ++++++++++++++++++++++-- drivers/clk/pxa/clk-pxa27x.c | 144 ++++++++++++++++++++++++++++++----- 4 files changed, 414 insertions(+), 27 deletions(-) diff --git a/drivers/clk/pxa/clk-pxa.c b/drivers/clk/pxa/clk-pxa.c index 29cee9e8d4d9..50fb9d0ea58d 100644 --- a/drivers/clk/pxa/clk-pxa.c +++ b/drivers/clk/pxa/clk-pxa.c @@ -18,6 +18,26 @@ #include #include "clk-pxa.h" +#define KHz 1000 +#define MHz (1000 * 1000) + +#define MDREFR_K0DB4 (1 << 29) /* SDCLK0 Divide by 4 Control/Status */ +#define MDREFR_K2FREE (1 << 25) /* SDRAM Free-Running Control */ +#define MDREFR_K1FREE (1 << 24) /* SDRAM Free-Running Control */ +#define MDREFR_K0FREE (1 << 23) /* SDRAM Free-Running Control */ +#define MDREFR_SLFRSH (1 << 22) /* SDRAM Self-Refresh Control/Status */ +#define MDREFR_APD (1 << 20) /* SDRAM/SSRAM Auto-Power-Down Enable */ +#define MDREFR_K2DB2 (1 << 19) /* SDCLK2 Divide by 2 Control/Status */ +#define MDREFR_K2RUN (1 << 18) /* SDCLK2 Run Control/Status */ +#define MDREFR_K1DB2 (1 << 17) /* SDCLK1 Divide by 2 Control/Status */ +#define MDREFR_K1RUN (1 << 16) /* SDCLK1 Run Control/Status */ +#define MDREFR_E1PIN (1 << 15) /* SDCKE1 Level Control/Status */ +#define MDREFR_K0DB2 (1 << 14) /* SDCLK0 Divide by 2 Control/Status */ +#define MDREFR_K0RUN (1 << 13) /* SDCLK0 Run Control/Status */ +#define MDREFR_E0PIN (1 << 12) /* SDCKE0 Level Control/Status */ +#define MDREFR_DB2_MASK (MDREFR_K2DB2 | MDREFR_K1DB2) +#define MDREFR_DRI_MASK 0xFFF + DEFINE_SPINLOCK(lock); static struct clk *pxa_clocks[CLK_MAX]; @@ -106,3 +126,122 @@ void __init clk_pxa_dt_common_init(struct device_node *np) { of_clk_add_provider(np, of_clk_src_onecell_get, &onecell_data); } + +void pxa2xx_core_turbo_switch(bool on) +{ + unsigned long flags; + unsigned int unused, clkcfg; + + local_irq_save(flags); + + asm("mrc p14, 0, %0, c6, c0, 0" : "=r" (clkcfg)); + clkcfg &= ~CLKCFG_TURBO & ~CLKCFG_HALFTURBO; + if (on) + clkcfg |= CLKCFG_TURBO; + clkcfg |= CLKCFG_FCS; + + asm volatile( + " b 2f\n" + " .align 5\n" + "1: mcr p14, 0, %1, c6, c0, 0\n" + " b 3f\n" + "2: b 1b\n" + "3: nop\n" + : "=&r" (unused) + : "r" (clkcfg) + : ); + + local_irq_restore(flags); +} + +void pxa2xx_cpll_change(struct pxa2xx_freq *freq, + u32 (*mdrefr_dri)(unsigned int), u32 *mdrefr, u32 *cccr) +{ + unsigned int clkcfg = freq->clkcfg; + unsigned int unused, preset_mdrefr, postset_mdrefr; + unsigned long flags; + + local_irq_save(flags); + + /* Calculate the next MDREFR. If we're slowing down the SDRAM clock + * we need to preset the smaller DRI before the change. If we're + * speeding up we need to set the larger DRI value after the change. + */ + preset_mdrefr = postset_mdrefr = readl(mdrefr); + if ((preset_mdrefr & MDREFR_DRI_MASK) > mdrefr_dri(freq->membus_khz)) { + preset_mdrefr = (preset_mdrefr & ~MDREFR_DRI_MASK); + preset_mdrefr |= mdrefr_dri(freq->membus_khz); + } + postset_mdrefr = + (postset_mdrefr & ~MDREFR_DRI_MASK) | + mdrefr_dri(freq->membus_khz); + + /* If we're dividing the memory clock by two for the SDRAM clock, this + * must be set prior to the change. Clearing the divide must be done + * after the change. + */ + if (freq->div2) { + preset_mdrefr |= MDREFR_DB2_MASK; + postset_mdrefr |= MDREFR_DB2_MASK; + } else { + postset_mdrefr &= ~MDREFR_DB2_MASK; + } + + /* Set new the CCCR and prepare CLKCFG */ + writel(freq->cccr, cccr); + + asm volatile( + " ldr r4, [%1]\n" + " b 2f\n" + " .align 5\n" + "1: str %3, [%1] /* preset the MDREFR */\n" + " mcr p14, 0, %2, c6, c0, 0 /* set CLKCFG[FCS] */\n" + " str %4, [%1] /* postset the MDREFR */\n" + " b 3f\n" + "2: b 1b\n" + "3: nop\n" + : "=&r" (unused) + : "r" (mdrefr), "r" (clkcfg), "r" (preset_mdrefr), + "r" (postset_mdrefr) + : "r4", "r5"); + + local_irq_restore(flags); +} + +int pxa2xx_determine_rate(struct clk_rate_request *req, + struct pxa2xx_freq *freqs, int nb_freqs) +{ + int i, closest_below = -1, closest_above = -1, ret = 0; + unsigned long rate; + + for (i = 0; i < nb_freqs; i++) { + rate = freqs[i].cpll; + if (rate == req->rate) + break; + if (rate < req->min_rate) + continue; + if (rate > req->max_rate) + continue; + if (rate <= req->rate) + closest_below = i; + if ((rate >= req->rate) && (closest_above == -1)) + closest_above = i; + } + + req->best_parent_hw = NULL; + + if (i < nb_freqs) + ret = 0; + else if (closest_below >= 0) + rate = freqs[closest_below].cpll; + else if (closest_above >= 0) + rate = freqs[closest_above].cpll; + else + ret = -EINVAL; + + pr_debug("%s(rate=%lu) rate=%lu: %d\n", __func__, req->rate, rate, ret); + if (!rate) + req->rate = rate; + + return ret; +} diff --git a/drivers/clk/pxa/clk-pxa.h b/drivers/clk/pxa/clk-pxa.h index d1de805df867..f60a7bccae4e 100644 --- a/drivers/clk/pxa/clk-pxa.h +++ b/drivers/clk/pxa/clk-pxa.h @@ -13,6 +13,11 @@ #ifndef _CLK_PXA_ #define _CLK_PXA_ +#define CLKCFG_TURBO 0x1 +#define CLKCFG_FCS 0x2 +#define CLKCFG_HALFTURBO 0x4 +#define CLKCFG_FASTBUS 0x8 + #define PARENTS(name) \ static const char *const name ## _parents[] __initconst #define MUX_RO_RATE_RO_OPS(name, clk_name) \ @@ -35,10 +40,27 @@ NULL, NULL, CLK_GET_RATE_NOCACHE); \ } -#define RATE_RO_OPS(name, clk_name) \ +#define RATE_RO_OPS(name, clk_name) \ + static struct clk_hw name ## _rate_hw; \ + static const struct clk_ops name ## _rate_ops = { \ + .recalc_rate = name ## _get_rate, \ + }; \ + static struct clk * __init clk_register_ ## name(void) \ + { \ + return clk_register_composite(NULL, clk_name, \ + name ## _parents, \ + ARRAY_SIZE(name ## _parents), \ + NULL, NULL, \ + &name ## _rate_hw, &name ## _rate_ops, \ + NULL, NULL, CLK_GET_RATE_NOCACHE); \ + } + +#define RATE_OPS(name, clk_name) \ static struct clk_hw name ## _rate_hw; \ static struct clk_ops name ## _rate_ops = { \ .recalc_rate = name ## _get_rate, \ + .set_rate = name ## _set_rate, \ + .determine_rate = name ## _determine_rate, \ }; \ static struct clk * __init clk_register_ ## name(void) \ { \ @@ -50,6 +72,24 @@ NULL, NULL, CLK_GET_RATE_NOCACHE); \ } +#define MUX_OPS(name, clk_name, flags) \ + static struct clk_hw name ## _mux_hw; \ + static const struct clk_ops name ## _mux_ops = { \ + .get_parent = name ## _get_parent, \ + .set_parent = name ## _set_parent, \ + .determine_rate = name ## _determine_rate, \ + }; \ + static struct clk * __init clk_register_ ## name(void) \ + { \ + return clk_register_composite(NULL, clk_name, \ + name ## _parents, \ + ARRAY_SIZE(name ## _parents), \ + &name ## _mux_hw, &name ## _mux_ops, \ + NULL, NULL, \ + NULL, NULL, \ + CLK_GET_RATE_NOCACHE | flags); \ + } + /* * CKEN clock type * This clock takes it source from 2 possible parents : @@ -95,6 +135,14 @@ struct desc_clk_cken { PXA_CKEN(dev_id, con_id, name, parents, 1, 1, 1, 1, \ NULL, cken_reg, cken_bit, flag) +struct pxa2xx_freq { + unsigned long cpll; + unsigned int membus_khz; + unsigned int cccr; + unsigned int div2; + unsigned int clkcfg; +}; + static int dummy_clk_set_parent(struct clk_hw *hw, u8 index) { return 0; @@ -105,4 +153,11 @@ extern void clkdev_pxa_register(int ckid, const char *con_id, extern int clk_pxa_cken_init(const struct desc_clk_cken *clks, int nb_clks); void clk_pxa_dt_common_init(struct device_node *np); +void pxa2xx_core_turbo_switch(bool on); +void pxa2xx_cpll_change(struct pxa2xx_freq *freq, + u32 (*mdrefr_dri)(unsigned int), u32 *mdrefr, + u32 *cccr); +int pxa2xx_determine_rate(struct clk_rate_request *req, + struct pxa2xx_freq *freqs, int nb_freqs); + #endif diff --git a/drivers/clk/pxa/clk-pxa25x.c b/drivers/clk/pxa/clk-pxa25x.c index 6a3009eec830..c53993b6bf87 100644 --- a/drivers/clk/pxa/clk-pxa25x.c +++ b/drivers/clk/pxa/clk-pxa25x.c @@ -18,6 +18,7 @@ #include #include #include +#include #include #include "clk-pxa.h" @@ -30,6 +31,17 @@ enum { PXA_CORE_TURBO, }; +#define PXA25x_CLKCFG(T) \ + (CLKCFG_FCS | \ + ((T) ? CLKCFG_TURBO : 0)) +#define PXA25x_CCCR(N2, M, L) (N2 << 7 | M << 5 | L) + +#define MDCNFG_DRAC2(mdcnfg) (((mdcnfg) >> 21) & 0x3) +#define MDCNFG_DRAC0(mdcnfg) (((mdcnfg) >> 5) & 0x3) + +/* Define the refresh period in mSec for the SDRAM and the number of rows */ +#define SDRAM_TREF 64 /* standard 64ms SDRAM */ + /* * Various clock factors driven by the CCCR register. */ @@ -48,6 +60,34 @@ static const char * const get_freq_khz[] = { "core", "run", "cpll", "memory" }; +static int get_sdram_rows(void) +{ + static int sdram_rows; + unsigned int drac2 = 0, drac0 = 0; + u32 mdcnfg; + + if (sdram_rows) + return sdram_rows; + + mdcnfg = readl_relaxed(MDCNFG); + + if (mdcnfg & (MDCNFG_DE2 | MDCNFG_DE3)) + drac2 = MDCNFG_DRAC2(mdcnfg); + + if (mdcnfg & (MDCNFG_DE0 | MDCNFG_DE1)) + drac0 = MDCNFG_DRAC0(mdcnfg); + + sdram_rows = 1 << (11 + max(drac0, drac2)); + return sdram_rows; +} + +static u32 mdrefr_dri(unsigned int freq_khz) +{ + u32 interval = freq_khz * SDRAM_TREF / get_sdram_rows(); + + return interval / 32; +} + /* * Get the clock frequency as reflected by CCCR and the turbo flag. * We assume these values have been applied via a fcs. @@ -139,6 +179,21 @@ static struct desc_clk_cken pxa25x_clocks[] __initdata = { clk_pxa25x_memory_parents, 0), }; +/* + * In this table, PXA25x_CCCR(N2, M, L) has the following meaning, where : + * - freq_cpll = n * m * L * 3.6864 MHz + * - n = N2 / 2 + * - m = 2^(M - 1), where 1 <= M <= 3 + * - l = L_clk_mult[L], ie. { 0, 27, 32, 36, 40, 45, 0, }[L] + */ +static struct pxa2xx_freq pxa25x_freqs[] = { + /* CPU MEMBUS CCCR DIV2 CCLKCFG */ + { 99532800, 99500, PXA25x_CCCR(2, 1, 1), 1, PXA25x_CLKCFG(1)}, + {199065600, 99500, PXA25x_CCCR(4, 1, 1), 0, PXA25x_CLKCFG(1)}, + {298598400, 99500, PXA25x_CCCR(3, 2, 1), 0, PXA25x_CLKCFG(1)}, + {398131200, 99500, PXA25x_CCCR(4, 2, 1), 0, PXA25x_CLKCFG(1)}, +}; + static u8 clk_pxa25x_core_get_parent(struct clk_hw *hw) { unsigned long clkcfg; @@ -151,13 +206,24 @@ static u8 clk_pxa25x_core_get_parent(struct clk_hw *hw) return PXA_CORE_RUN; } -static unsigned long clk_pxa25x_core_get_rate(struct clk_hw *hw, - unsigned long parent_rate) +static int clk_pxa25x_core_set_parent(struct clk_hw *hw, u8 index) { - return parent_rate; + if (index > PXA_CORE_TURBO) + return -EINVAL; + + pxa2xx_core_turbo_switch(index == PXA_CORE_TURBO); + + return 0; } + +static int clk_pxa25x_core_determine_rate(struct clk_hw *hw, + struct clk_rate_request *req) +{ + return __clk_mux_determine_rate(hw, req); +} + PARENTS(clk_pxa25x_core) = { "run", "cpll" }; -MUX_RO_RATE_RO_OPS(clk_pxa25x_core, "core"); +MUX_OPS(clk_pxa25x_core, "core", CLK_SET_RATE_PARENT); static unsigned long clk_pxa25x_run_get_rate(struct clk_hw *hw, unsigned long parent_rate) @@ -184,8 +250,33 @@ static unsigned long clk_pxa25x_cpll_get_rate(struct clk_hw *hw, return m * l * n2 * parent_rate / 2; } + +static int clk_pxa25x_cpll_determine_rate(struct clk_hw *hw, + struct clk_rate_request *req) +{ + return pxa2xx_determine_rate(req, pxa25x_freqs, + ARRAY_SIZE(pxa25x_freqs)); +} + +static int clk_pxa25x_cpll_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + int i; + + pr_debug("%s(rate=%lu parent_rate=%lu)\n", __func__, rate, parent_rate); + for (i = 0; i < ARRAY_SIZE(pxa25x_freqs); i++) + if (pxa25x_freqs[i].cpll == rate) + break; + + if (i >= ARRAY_SIZE(pxa25x_freqs)) + return -EINVAL; + + pxa2xx_cpll_change(&pxa25x_freqs[i], mdrefr_dri, MDREFR, CCCR); + + return 0; +} PARENTS(clk_pxa25x_cpll) = { "osc_3_6864mhz" }; -RATE_RO_OPS(clk_pxa25x_cpll, "cpll"); +RATE_OPS(clk_pxa25x_cpll, "cpll"); static void __init pxa25x_register_core(void) { diff --git a/drivers/clk/pxa/clk-pxa27x.c b/drivers/clk/pxa/clk-pxa27x.c index 9fb40e884999..25a30194d27a 100644 --- a/drivers/clk/pxa/clk-pxa27x.c +++ b/drivers/clk/pxa/clk-pxa27x.c @@ -17,6 +17,8 @@ #include #include +#include + #include #include "clk-pxa.h" @@ -45,11 +47,52 @@ enum { PXA_MEM_RUN, }; +#define PXA27x_CLKCFG(B, HT, T) \ + (CLKCFG_FCS | \ + ((B) ? CLKCFG_FASTBUS : 0) | \ + ((HT) ? CLKCFG_HALFTURBO : 0) | \ + ((T) ? CLKCFG_TURBO : 0)) +#define PXA27x_CCCR(A, L, N2) (A << 25 | N2 << 7 | L) + +#define MDCNFG_DRAC2(mdcnfg) (((mdcnfg) >> 21) & 0x3) +#define MDCNFG_DRAC0(mdcnfg) (((mdcnfg) >> 5) & 0x3) + +/* Define the refresh period in mSec for the SDRAM and the number of rows */ +#define SDRAM_TREF 64 /* standard 64ms SDRAM */ + static const char * const get_freq_khz[] = { "core", "run", "cpll", "memory", "system_bus" }; +static int get_sdram_rows(void) +{ + static int sdram_rows; + unsigned int drac2 = 0, drac0 = 0; + u32 mdcnfg; + + if (sdram_rows) + return sdram_rows; + + mdcnfg = readl_relaxed(MDCNFG); + + if (mdcnfg & (MDCNFG_DE2 | MDCNFG_DE3)) + drac2 = MDCNFG_DRAC2(mdcnfg); + + if (mdcnfg & (MDCNFG_DE0 | MDCNFG_DE1)) + drac0 = MDCNFG_DRAC0(mdcnfg); + + sdram_rows = 1 << (11 + max(drac0, drac2)); + return sdram_rows; +} + +static u32 mdrefr_dri(unsigned int freq_khz) +{ + u32 interval = freq_khz * SDRAM_TREF / get_sdram_rows(); + + return (interval - 31) / 32; +} + /* * Get the clock frequency as reflected by CCSR and the turbo flag. * We assume these values have been applied via a fcs. @@ -145,6 +188,42 @@ static struct desc_clk_cken pxa27x_clocks[] __initdata = { }; +/* + * PXA270 definitions + * + * For the PXA27x: + * Control variables are A, L, 2N for CCCR; B, HT, T for CLKCFG. + * + * A = 0 => memory controller clock from table 3-7, + * A = 1 => memory controller clock = system bus clock + * Run mode frequency = 13 MHz * L + * Turbo mode frequency = 13 MHz * L * N + * System bus frequency = 13 MHz * L / (B + 1) + * + * In CCCR: + * A = 1 + * L = 16 oscillator to run mode ratio + * 2N = 6 2 * (turbo mode to run mode ratio) + * + * In CCLKCFG: + * B = 1 Fast bus mode + * HT = 0 Half-Turbo mode + * T = 1 Turbo mode + * + * For now, just support some of the combinations in table 3-7 of + * PXA27x Processor Family Developer's Manual to simplify frequency + * change sequences. + */ +static struct pxa2xx_freq pxa27x_freqs[] = { + {104000000, 104000, PXA27x_CCCR(1, 8, 2), 0, PXA27x_CLKCFG(1, 0, 1) }, + {156000000, 104000, PXA27x_CCCR(1, 8, 3), 0, PXA27x_CLKCFG(1, 0, 1) }, + {208000000, 208000, PXA27x_CCCR(0, 16, 2), 1, PXA27x_CLKCFG(0, 0, 1) }, + {312000000, 208000, PXA27x_CCCR(1, 16, 3), 1, PXA27x_CLKCFG(1, 0, 1) }, + {416000000, 208000, PXA27x_CCCR(1, 16, 4), 1, PXA27x_CLKCFG(1, 0, 1) }, + {520000000, 208000, PXA27x_CCCR(1, 16, 5), 1, PXA27x_CLKCFG(1, 0, 1) }, + {624000000, 208000, PXA27x_CCCR(1, 16, 6), 1, PXA27x_CLKCFG(1, 0, 1) }, +}; + static unsigned long clk_pxa27x_cpll_get_rate(struct clk_hw *hw, unsigned long parent_rate) { @@ -164,8 +243,33 @@ static unsigned long clk_pxa27x_cpll_get_rate(struct clk_hw *hw, return N; } + +static int clk_pxa27x_cpll_determine_rate(struct clk_hw *hw, + struct clk_rate_request *req) +{ + return pxa2xx_determine_rate(req, pxa27x_freqs, + ARRAY_SIZE(pxa27x_freqs)); +} + +static int clk_pxa27x_cpll_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + int i; + + pr_debug("%s(rate=%lu parent_rate=%lu)\n", __func__, rate, parent_rate); + for (i = 0; i < ARRAY_SIZE(pxa27x_freqs); i++) + if (pxa27x_freqs[i].cpll == rate) + break; + + if (i >= ARRAY_SIZE(pxa27x_freqs)) + return -EINVAL; + + pxa2xx_cpll_change(&pxa27x_freqs[i], mdrefr_dri, MDREFR, CCCR); + return 0; +} + PARENTS(clk_pxa27x_cpll) = { "osc_13mhz" }; -RATE_RO_OPS(clk_pxa27x_cpll, "cpll"); +RATE_OPS(clk_pxa27x_cpll, "cpll"); static unsigned long clk_pxa27x_lcd_base_get_rate(struct clk_hw *hw, unsigned long parent_rate) @@ -217,25 +321,6 @@ static void __init pxa27x_register_plls(void) clk_register_fixed_factor(NULL, "ppll_312mhz", "osc_13mhz", 0, 24, 1); } -static unsigned long clk_pxa27x_core_get_rate(struct clk_hw *hw, - unsigned long parent_rate) -{ - unsigned long clkcfg; - unsigned int ht, osc_forced; - unsigned long ccsr = readl(CCSR); - - osc_forced = ccsr & (1 << CCCR_CPDIS_BIT); - asm("mrc\tp14, 0, %0, c6, c0, 0" : "=r" (clkcfg)); - ht = clkcfg & (1 << 2); - - if (osc_forced) - return parent_rate; - if (ht) - return parent_rate / 2; - else - return parent_rate; -} - static u8 clk_pxa27x_core_get_parent(struct clk_hw *hw) { unsigned long clkcfg; @@ -254,8 +339,25 @@ static u8 clk_pxa27x_core_get_parent(struct clk_hw *hw) return PXA_CORE_TURBO; return PXA_CORE_RUN; } + +static int clk_pxa27x_core_set_parent(struct clk_hw *hw, u8 index) +{ + if (index > PXA_CORE_TURBO) + return -EINVAL; + + pxa2xx_core_turbo_switch(index == PXA_CORE_TURBO); + + return 0; +} + +static int clk_pxa27x_core_determine_rate(struct clk_hw *hw, + struct clk_rate_request *req) +{ + return __clk_mux_determine_rate(hw, req); +} + PARENTS(clk_pxa27x_core) = { "osc_13mhz", "run", "cpll" }; -MUX_RO_RATE_RO_OPS(clk_pxa27x_core, "core"); +MUX_OPS(clk_pxa27x_core, "core", CLK_SET_RATE_PARENT); static unsigned long clk_pxa27x_run_get_rate(struct clk_hw *hw, unsigned long parent_rate) -- 2.20.1