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authorLinus Walleij <linus.walleij@linaro.org>2016-08-22 11:19:33 +0200
committerStephen Boyd <sboyd@codeaurora.org>2016-08-25 13:03:52 -0700
commit5e23c593057520db45b089644863989d4b21e31f (patch)
tree3add6d733e30531e73e756a55584901abe85016b /drivers/clk/versatile
parent50581cc4f14f0f704b967cd4664a34d7644be816 (diff)
downloadlinux-5e23c593057520db45b089644863989d4b21e31f.tar.bz2
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')
-rw-r--r--drivers/clk/versatile/clk-icst.c174
1 files changed, 160 insertions, 14 deletions
diff --git a/drivers/clk/versatile/clk-icst.c b/drivers/clk/versatile/clk-icst.c
index 5e9b65278e4c..8f06473b72ff 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