diff options
author | Linus Walleij <linus.walleij@linaro.org> | 2016-08-22 11:19:33 +0200 |
---|---|---|
committer | Stephen Boyd <sboyd@codeaurora.org> | 2016-08-25 13:03:52 -0700 |
commit | 5e23c593057520db45b089644863989d4b21e31f (patch) | |
tree | 3add6d733e30531e73e756a55584901abe85016b /drivers/clk/versatile/clk-icst.c | |
parent | 50581cc4f14f0f704b967cd4664a34d7644be816 (diff) | |
download | op-kernel-dev-5e23c593057520db45b089644863989d4b21e31f.zip op-kernel-dev-5e23c593057520db45b089644863989d4b21e31f.tar.gz |
clk: versatile/icst: add Integrator core module clocks
The Integrator/AP and Integrator/CP have special derivatives
of the ICST525 control registers, where some bits have been
hardwired but others are possible to adjust, resulting in a
control register that makes it possible to set an even,
desired megahertz value.
The Integrator/AP and Integrator/CP have slightly different
layout so we support them using different compatible
strings.
After adding these clocks, the Integrator-specific cpufreq
driver can be switched over to use the generic operating
point device tree cpufreq driver.
Instead of simply writing a value to the oscillator control
register we switch to the more elaborate method of providing
a bitmask and use regmap_update_bits() to poke the right bits
for the desired frequency, this is needed since these control
registers sometimes control more than one clock.
Cc: Russell King <linux@armlinux.org.uk>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Diffstat (limited to 'drivers/clk/versatile/clk-icst.c')
-rw-r--r-- | drivers/clk/versatile/clk-icst.c | 174 |
1 files changed, 160 insertions, 14 deletions
diff --git a/drivers/clk/versatile/clk-icst.c b/drivers/clk/versatile/clk-icst.c index 5e9b652..8f06473 100644 --- a/drivers/clk/versatile/clk-icst.c +++ b/drivers/clk/versatile/clk-icst.c @@ -27,6 +27,21 @@ /* Magic unlocking token used on all Versatile boards */ #define VERSATILE_LOCK_VAL 0xA05F +#define VERSATILE_AUX_OSC_BITS 0x7FFFF +#define INTEGRATOR_AP_CM_BITS 0xFF +#define INTEGRATOR_CP_CM_CORE_BITS 0x7FF +#define INTEGRATOR_CP_CM_MEM_BITS 0x7FF000 + +/** + * enum icst_control_type - the type of ICST control register + */ +enum icst_control_type { + ICST_VERSATILE, /* The standard type, all control bits available */ + ICST_INTEGRATOR_AP_CM, /* Only 8 bits of VDW available */ + ICST_INTEGRATOR_CP_CM_CORE, /* Only 8 bits of VDW and 3 bits of OD */ + ICST_INTEGRATOR_CP_CM_MEM, /* Only 8 bits of VDW and 3 bits of OD */ +}; + /** * struct clk_icst - ICST VCO clock wrapper * @hw: corresponding clock hardware entry @@ -34,6 +49,7 @@ * @lockreg: VCO lock register address * @params: parameters for this ICST instance * @rate: current rate + * @ctype: the type of control register for the ICST */ struct clk_icst { struct clk_hw hw; @@ -42,6 +58,7 @@ struct clk_icst { u32 lockreg_off; struct icst_params *params; unsigned long rate; + enum icst_control_type ctype; }; #define to_icst(_hw) container_of(_hw, struct clk_icst, hw) @@ -59,6 +76,44 @@ static int vco_get(struct clk_icst *icst, struct icst_vco *vco) ret = regmap_read(icst->map, icst->vcoreg_off, &val); if (ret) return ret; + + /* + * The Integrator/AP core clock can only access the low eight + * bits of the v PLL divider. Bit 8 is tied low and always zero, + * r is hardwired to 22 and output divider s is hardwired to 1 + * (divide by 2) according to the document + * "Integrator CM926EJ-S, CM946E-S, CM966E-S, CM1026EJ-S and + * CM1136JF-S User Guide" ARM DUI 0138E, page 3-13 thru 3-14. + */ + if (icst->ctype == ICST_INTEGRATOR_AP_CM) { + vco->v = val & INTEGRATOR_AP_CM_BITS; + vco->r = 22; + vco->s = 1; + return 0; + } + + /* + * The Integrator/CP core clock can access the low eight bits + * of the v PLL divider. Bit 8 is tied low and always zero, + * r is hardwired to 22 and the output divider s is accessible + * in bits 8 thru 10 according to the document + * "Integrator/CM940T, CM920T, CM740T, and CM720T User Guide" + * ARM DUI 0157A, page 3-20 thru 3-23 and 4-10. + */ + if (icst->ctype == ICST_INTEGRATOR_CP_CM_CORE) { + vco->v = val & 0xFF; + vco->r = 22; + vco->s = (val >> 8) & 7; + return 0; + } + + if (icst->ctype == ICST_INTEGRATOR_CP_CM_MEM) { + vco->v = (val >> 12) & 0xFF; + vco->r = 22; + vco->s = (val >> 20) & 7; + return 0; + } + vco->v = val & 0x1ff; vco->r = (val >> 9) & 0x7f; vco->s = (val >> 16) & 03; @@ -72,22 +127,52 @@ static int vco_get(struct clk_icst *icst, struct icst_vco *vco) */ static int vco_set(struct clk_icst *icst, struct icst_vco vco) { + u32 mask; u32 val; int ret; - ret = regmap_read(icst->map, icst->vcoreg_off, &val); - if (ret) - return ret; + /* Mask the bits used by the VCO */ + switch (icst->ctype) { + case ICST_INTEGRATOR_AP_CM: + mask = INTEGRATOR_AP_CM_BITS; + val = vco.v & 0xFF; + if (vco.v & 0x100) + pr_err("ICST error: tried to set bit 8 of VDW\n"); + if (vco.s != 1) + pr_err("ICST error: tried to use VOD != 1\n"); + if (vco.r != 22) + pr_err("ICST error: tried to use RDW != 22\n"); + break; + case ICST_INTEGRATOR_CP_CM_CORE: + mask = INTEGRATOR_CP_CM_CORE_BITS; /* Uses 12 bits */ + val = (vco.v & 0xFF) | vco.s << 8; + if (vco.v & 0x100) + pr_err("ICST error: tried to set bit 8 of VDW\n"); + if (vco.r != 22) + pr_err("ICST error: tried to use RDW != 22\n"); + break; + case ICST_INTEGRATOR_CP_CM_MEM: + mask = INTEGRATOR_CP_CM_MEM_BITS; /* Uses 12 bits */ + val = ((vco.v & 0xFF) << 12) | (vco.s << 20); + if (vco.v & 0x100) + pr_err("ICST error: tried to set bit 8 of VDW\n"); + if (vco.r != 22) + pr_err("ICST error: tried to use RDW != 22\n"); + break; + default: + /* Regular auxilary oscillator */ + mask = VERSATILE_AUX_OSC_BITS; + val = vco.v | (vco.r << 9) | (vco.s << 16); + break; + } - /* Mask the 18 bits used by the VCO */ - val &= ~0x7ffff; - val |= vco.v | (vco.r << 9) | (vco.s << 16); + pr_debug("ICST: new val = 0x%08x\n", val); /* This magic unlocks the VCO so it can be controlled */ ret = regmap_write(icst->map, icst->lockreg_off, VERSATILE_LOCK_VAL); if (ret) return ret; - ret = regmap_write(icst->map, icst->vcoreg_off, val); + ret = regmap_update_bits(icst->map, icst->vcoreg_off, mask, val); if (ret) return ret; /* This locks the VCO again */ @@ -121,6 +206,25 @@ static long icst_round_rate(struct clk_hw *hw, unsigned long rate, struct clk_icst *icst = to_icst(hw); struct icst_vco vco; + if (icst->ctype == ICST_INTEGRATOR_AP_CM || + icst->ctype == ICST_INTEGRATOR_CP_CM_CORE) { + if (rate <= 12000000) + return 12000000; + if (rate >= 160000000) + return 160000000; + /* Slam to closest megahertz */ + return DIV_ROUND_CLOSEST(rate, 1000000) * 1000000; + } + + if (icst->ctype == ICST_INTEGRATOR_CP_CM_MEM) { + if (rate <= 6000000) + return 6000000; + if (rate >= 66000000) + return 66000000; + /* Slam to closest 0.5 megahertz */ + return DIV_ROUND_CLOSEST(rate, 500000) * 500000; + } + vco = icst_hz_to_vco(icst->params, rate); return icst_hz(icst->params, vco); } @@ -148,7 +252,8 @@ static struct clk *icst_clk_setup(struct device *dev, const struct clk_icst_desc *desc, const char *name, const char *parent_name, - struct regmap *map) + struct regmap *map, + enum icst_control_type ctype) { struct clk *clk; struct clk_icst *icst; @@ -178,6 +283,7 @@ static struct clk *icst_clk_setup(struct device *dev, icst->params = pclone; icst->vcoreg_off = desc->vco_offset; icst->lockreg_off = desc->lock_offset; + icst->ctype = ctype; clk = clk_register(dev, &icst->hw); if (IS_ERR(clk)) { @@ -206,7 +312,8 @@ struct clk *icst_clk_register(struct device *dev, pr_err("could not initialize ICST regmap\n"); return ERR_CAST(map); } - return icst_clk_setup(dev, desc, name, parent_name, map); + return icst_clk_setup(dev, desc, name, parent_name, map, + ICST_VERSATILE); } EXPORT_SYMBOL_GPL(icst_clk_register); @@ -239,6 +346,28 @@ static const struct icst_params icst307_params = { .idx2s = icst307_idx2s, }; +/** + * The core modules on the Integrator/AP and Integrator/CP have + * especially crippled ICST525 control. + */ +static const struct icst_params icst525_apcp_cm_params = { + .vco_max = ICST525_VCO_MAX_5V, + .vco_min = ICST525_VCO_MIN, + /* Minimum 12 MHz, VDW = 4 */ + .vd_min = 12, + /* + * Maximum 160 MHz, VDW = 152 for all core modules, but + * CM926EJ-S, CM1026EJ-S and CM1136JF-S can actually + * go to 200 MHz (max VDW = 192). + */ + .vd_max = 192, + /* r is hardcoded to 22 and this is the actual divisor, +2 */ + .rd_min = 24, + .rd_max = 24, + .s2div = icst525_s2div, + .idx2s = icst525_idx2s, +}; + static void __init of_syscon_icst_setup(struct device_node *np) { struct device_node *parent; @@ -247,6 +376,7 @@ static void __init of_syscon_icst_setup(struct device_node *np) const char *name = np->name; const char *parent_name; struct clk *regclk; + enum icst_control_type ctype; /* We do not release this reference, we are using it perpetually */ parent = of_get_parent(np); @@ -269,11 +399,22 @@ static void __init of_syscon_icst_setup(struct device_node *np) return; } - if (of_device_is_compatible(np, "arm,syscon-icst525")) + if (of_device_is_compatible(np, "arm,syscon-icst525")) { icst_desc.params = &icst525_params; - else if (of_device_is_compatible(np, "arm,syscon-icst307")) + ctype = ICST_VERSATILE; + } else if (of_device_is_compatible(np, "arm,syscon-icst307")) { icst_desc.params = &icst307_params; - else { + ctype = ICST_VERSATILE; + } else if (of_device_is_compatible(np, "arm,syscon-icst525-integratorap-cm")) { + icst_desc.params = &icst525_apcp_cm_params; + ctype = ICST_INTEGRATOR_AP_CM; + } else if (of_device_is_compatible(np, "arm,syscon-icst525-integratorcp-cm-core")) { + icst_desc.params = &icst525_apcp_cm_params; + ctype = ICST_INTEGRATOR_CP_CM_CORE; + } else if (of_device_is_compatible(np, "arm,syscon-icst525-integratorcp-cm-mem")) { + icst_desc.params = &icst525_apcp_cm_params; + ctype = ICST_INTEGRATOR_CP_CM_MEM; + } else { pr_err("unknown ICST clock %s\n", name); return; } @@ -281,7 +422,7 @@ static void __init of_syscon_icst_setup(struct device_node *np) /* Parent clock name is not the same as node parent */ parent_name = of_clk_get_parent_name(np, 0); - regclk = icst_clk_setup(NULL, &icst_desc, name, parent_name, map); + regclk = icst_clk_setup(NULL, &icst_desc, name, parent_name, map, ctype); if (IS_ERR(regclk)) { pr_err("error setting up syscon ICST clock %s\n", name); return; @@ -294,5 +435,10 @@ CLK_OF_DECLARE(arm_syscon_icst525_clk, "arm,syscon-icst525", of_syscon_icst_setup); CLK_OF_DECLARE(arm_syscon_icst307_clk, "arm,syscon-icst307", of_syscon_icst_setup); - +CLK_OF_DECLARE(arm_syscon_integratorap_cm_clk, + "arm,syscon-icst525-integratorap-cm", of_syscon_icst_setup); +CLK_OF_DECLARE(arm_syscon_integratorcp_cm_core_clk, + "arm,syscon-icst525-integratorcp-cm-core", of_syscon_icst_setup); +CLK_OF_DECLARE(arm_syscon_integratorcp_cm_mem_clk, + "arm,syscon-icst525-integratorcp-cm-mem", of_syscon_icst_setup); #endif |