diff options
Diffstat (limited to 'drivers/clk/pxa/clk-pxa25x.c')
| -rw-r--r-- | drivers/clk/pxa/clk-pxa25x.c | 114 |
1 files changed, 103 insertions, 11 deletions
diff --git a/drivers/clk/pxa/clk-pxa25x.c b/drivers/clk/pxa/clk-pxa25x.c index a98b98e2a9e4..c53993b6bf87 100644 --- a/drivers/clk/pxa/clk-pxa25x.c +++ b/drivers/clk/pxa/clk-pxa25x.c @@ -18,6 +18,7 @@ #include <linux/io.h> #include <linux/of.h> #include <mach/pxa2xx-regs.h> +#include <mach/smemc.h> #include <dt-bindings/clock/pxa-clock.h> #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) @@ -182,17 +248,42 @@ static unsigned long clk_pxa25x_cpll_get_rate(struct clk_hw *hw, m = M_clk_mult[(cccr >> 5) & 0x03]; n2 = N2_clk_mult[(cccr >> 7) & 0x07]; - if (t) - return m * l * n2 * parent_rate / 2; - return m * l * parent_rate; + 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) { - clk_register_clk_pxa25x_cpll(); - clk_register_clk_pxa25x_run(); + clkdev_pxa_register(CLK_NONE, "cpll", NULL, + clk_register_clk_pxa25x_cpll()); + clkdev_pxa_register(CLK_NONE, "run", NULL, + clk_register_clk_pxa25x_run()); clkdev_pxa_register(CLK_CORE, "core", NULL, clk_register_clk_pxa25x_core()); } @@ -214,7 +305,8 @@ static void __init pxa25x_base_clocks_init(void) { pxa25x_register_plls(); pxa25x_register_core(); - clk_register_clk_pxa25x_memory(); + clkdev_pxa_register(CLK_NONE, "system_bus", NULL, + clk_register_clk_pxa25x_memory()); } #define DUMMY_CLK(_con_id, _dev_id, _parent) \ |