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authorLinus Walleij <linus.walleij@linaro.org>2016-08-27 14:01:19 +0200
committerStephen Boyd <sboyd@codeaurora.org>2016-08-29 11:38:51 -0700
commitfa62e10d2613b9e9edbe944b890644b30e9d4ed7 (patch)
treec416b5308d2d25d7a82f9fb1be26ac745271457e /drivers/clk/versatile
parent74002fcde01d8acb4ce68878e9998fad51fe7925 (diff)
clk: versatile/icst: support for AP baseboard clocks
This adds support for the two ICST525-based clocks on the Integrator/AP baseboard, as documented in the board manual "Integrator/AP ASIC Development Motherboard", ARM DUI0098 B, pages 3-15 thru 3-18. Cc: Russell King <linux@armlinux.org.uk> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> [sboyd@codeaurora.org: fixed uninitialized val warning] Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Diffstat (limited to 'drivers/clk/versatile')
-rw-r--r--drivers/clk/versatile/clk-icst.c136
1 files changed, 136 insertions, 0 deletions
diff --git a/drivers/clk/versatile/clk-icst.c b/drivers/clk/versatile/clk-icst.c
index 8f06473b72ff..4faa94440779 100644
--- a/drivers/clk/versatile/clk-icst.c
+++ b/drivers/clk/versatile/clk-icst.c
@@ -29,15 +29,20 @@
#define VERSATILE_AUX_OSC_BITS 0x7FFFF
#define INTEGRATOR_AP_CM_BITS 0xFF
+#define INTEGRATOR_AP_SYS_BITS 0xFF
#define INTEGRATOR_CP_CM_CORE_BITS 0x7FF
#define INTEGRATOR_CP_CM_MEM_BITS 0x7FF000
+#define INTEGRATOR_AP_PCI_25_33_MHZ BIT(8)
+
/**
* 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_AP_SYS, /* Only 8 bits of VDW available */
+ ICST_INTEGRATOR_AP_PCI, /* Odd bit pattern storage */
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 */
};
@@ -93,6 +98,38 @@ static int vco_get(struct clk_icst *icst, struct icst_vco *vco)
}
/*
+ * The Integrator/AP system clock on the base board can only
+ * access the low eight bits of the v PLL divider. Bit 8 is tied low
+ * and always zero, r is hardwired to 46, and the output divider is
+ * hardwired to 3 (divide by 4) according to the document
+ * "Integrator AP ASIC Development Motherboard" ARM DUI 0098B,
+ * page 3-16.
+ */
+ if (icst->ctype == ICST_INTEGRATOR_AP_SYS) {
+ vco->v = val & INTEGRATOR_AP_SYS_BITS;
+ vco->r = 46;
+ vco->s = 3;
+ return 0;
+ }
+
+ /*
+ * The Integrator/AP PCI clock is using an odd pattern to create
+ * the child clock, basically a single bit called DIVX/Y is used
+ * to select between two different hardwired values: setting the
+ * bit to 0 yields v = 17, r = 22 and OD = 1, whereas setting the
+ * bit to 1 yields v = 14, r = 14 and OD = 1 giving the frequencies
+ * 33 or 25 MHz respectively.
+ */
+ if (icst->ctype == ICST_INTEGRATOR_AP_PCI) {
+ bool divxy = !!(val & INTEGRATOR_AP_PCI_25_33_MHZ);
+
+ vco->v = divxy ? 17 : 14;
+ vco->r = divxy ? 22 : 14;
+ 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
@@ -143,6 +180,16 @@ static int vco_set(struct clk_icst *icst, struct icst_vco vco)
if (vco.r != 22)
pr_err("ICST error: tried to use RDW != 22\n");
break;
+ case ICST_INTEGRATOR_AP_SYS:
+ mask = INTEGRATOR_AP_SYS_BITS;
+ val = vco.v & 0xFF;
+ if (vco.v & 0x100)
+ pr_err("ICST error: tried to set bit 8 of VDW\n");
+ if (vco.s != 3)
+ pr_err("ICST error: tried to use VOD != 1\n");
+ if (vco.r != 46)
+ 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;
@@ -225,6 +272,27 @@ static long icst_round_rate(struct clk_hw *hw, unsigned long rate,
return DIV_ROUND_CLOSEST(rate, 500000) * 500000;
}
+ if (icst->ctype == ICST_INTEGRATOR_AP_SYS) {
+ /* Divides between 3 and 50 MHz in steps of 0.25 MHz */
+ if (rate <= 3000000)
+ return 3000000;
+ if (rate >= 50000000)
+ return 5000000;
+ /* Slam to closest 0.25 MHz */
+ return DIV_ROUND_CLOSEST(rate, 250000) * 250000;
+ }
+
+ if (icst->ctype == ICST_INTEGRATOR_AP_PCI) {
+ /*
+ * If we're below or less than halfway from 25 to 33 MHz
+ * select 25 MHz
+ */
+ if (rate <= 25000000 || rate < 29000000)
+ return 25000000;
+ /* Else just return the default frequency */
+ return 33000000;
+ }
+
vco = icst_hz_to_vco(icst->params, rate);
return icst_hz(icst->params, vco);
}
@@ -235,6 +303,36 @@ static int icst_set_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_PCI) {
+ /* This clock is especially primitive */
+ unsigned int val;
+ int ret;
+
+ if (rate == 25000000) {
+ val = 0;
+ } else if (rate == 33000000) {
+ val = INTEGRATOR_AP_PCI_25_33_MHZ;
+ } else {
+ pr_err("ICST: cannot set PCI frequency %lu\n",
+ rate);
+ return -EINVAL;
+ }
+ ret = regmap_write(icst->map, icst->lockreg_off,
+ VERSATILE_LOCK_VAL);
+ if (ret)
+ return ret;
+ ret = regmap_update_bits(icst->map, icst->vcoreg_off,
+ INTEGRATOR_AP_PCI_25_33_MHZ,
+ val);
+ if (ret)
+ return ret;
+ /* This locks the VCO again */
+ ret = regmap_write(icst->map, icst->lockreg_off, 0);
+ if (ret)
+ return ret;
+ return 0;
+ }
+
if (parent_rate)
icst->params->ref = parent_rate;
vco = icst_hz_to_vco(icst->params, rate);
@@ -368,6 +466,34 @@ static const struct icst_params icst525_apcp_cm_params = {
.idx2s = icst525_idx2s,
};
+static const struct icst_params icst525_ap_sys_params = {
+ .vco_max = ICST525_VCO_MAX_5V,
+ .vco_min = ICST525_VCO_MIN,
+ /* Minimum 3 MHz, VDW = 4 */
+ .vd_min = 3,
+ /* Maximum 50 MHz, VDW = 192 */
+ .vd_max = 50,
+ /* r is hardcoded to 46 and this is the actual divisor, +2 */
+ .rd_min = 48,
+ .rd_max = 48,
+ .s2div = icst525_s2div,
+ .idx2s = icst525_idx2s,
+};
+
+static const struct icst_params icst525_ap_pci_params = {
+ .vco_max = ICST525_VCO_MAX_5V,
+ .vco_min = ICST525_VCO_MIN,
+ /* Minimum 25 MHz */
+ .vd_min = 25,
+ /* Maximum 33 MHz */
+ .vd_max = 33,
+ /* r is hardcoded to 14 or 22 and this is the actual divisors +2 */
+ .rd_min = 16,
+ .rd_max = 24,
+ .s2div = icst525_s2div,
+ .idx2s = icst525_idx2s,
+};
+
static void __init of_syscon_icst_setup(struct device_node *np)
{
struct device_node *parent;
@@ -408,6 +534,12 @@ static void __init of_syscon_icst_setup(struct device_node *np)
} 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-integratorap-sys")) {
+ icst_desc.params = &icst525_ap_sys_params;
+ ctype = ICST_INTEGRATOR_AP_SYS;
+ } else if (of_device_is_compatible(np, "arm,syscon-icst525-integratorap-pci")) {
+ icst_desc.params = &icst525_ap_pci_params;
+ ctype = ICST_INTEGRATOR_AP_PCI;
} 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;
@@ -437,6 +569,10 @@ 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_integratorap_sys_clk,
+ "arm,syscon-icst525-integratorap-sys", of_syscon_icst_setup);
+CLK_OF_DECLARE(arm_syscon_integratorap_pci_clk,
+ "arm,syscon-icst525-integratorap-pci", 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,